From 06d61ffe413a8e2a6c3087d167ea6690a7dd6604 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Tue, 2 Dec 2025 21:06:28 +0100
Subject: [PATCH 01/20] build: versioning framework-only build with tests run
 configuration

---
 .run/spectrum framework-only no tests.run.xml | 37 +++++++++++++++++++
 .run/spectrum framework-only.run.xml          |  1 -
 2 files changed, 37 insertions(+), 1 deletion(-)
 create mode 100644 .run/spectrum framework-only no tests.run.xml

diff --git a/.run/spectrum framework-only no tests.run.xml b/.run/spectrum framework-only no tests.run.xml
new file mode 100644
index 000000000..35b5d922c
--- /dev/null
+++ b/.run/spectrum framework-only no tests.run.xml	
@@ -0,0 +1,37 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="spectrum framework-only no tests" type="MavenRunConfiguration" factoryName="Maven">
+    <MavenSettings>
+      <option name="myGeneralSettings" />
+      <option name="myRunnerSettings" />
+      <option name="myRunnerParameters">
+        <MavenRunnerParameters>
+          <option name="cmdOptions" />
+          <option name="profiles">
+            <set />
+          </option>
+          <option name="goals">
+            <list>
+              <option value="install" />
+              <option value="-DskipTests" />
+              <option value="-DskipSign" />
+              <option value="-ntp" />
+              <option value="-P" />
+              <option value="framework-only" />
+            </list>
+          </option>
+          <option name="multimoduleDir" />
+          <option name="pomFileName" />
+          <option name="profilesMap">
+            <map />
+          </option>
+          <option name="projectsCmdOptionValues">
+            <list />
+          </option>
+          <option name="resolveToWorkspace" value="false" />
+          <option name="workingDirPath" value="$PROJECT_DIR$" />
+        </MavenRunnerParameters>
+      </option>
+    </MavenSettings>
+    <method v="2" />
+  </configuration>
+</component>
\ No newline at end of file
diff --git a/.run/spectrum framework-only.run.xml b/.run/spectrum framework-only.run.xml
index 61983155b..f474ce7f6 100644
--- a/.run/spectrum framework-only.run.xml	
+++ b/.run/spectrum framework-only.run.xml	
@@ -12,7 +12,6 @@
           <option name="goals">
             <list>
               <option value="install" />
-              <option value="-DskipTests" />
               <option value="-DskipSign" />
               <option value="-ntp" />
               <option value="-P" />

From bb0c862c158f624fe30a7008367b58deb8fde72f Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Tue, 2 Dec 2025 22:39:25 +0100
Subject: [PATCH 02/20] feat: introducing external interpolation to resolve
 system properties and env variables without the need of declaring the
 corresponding key in the configuration yaml

---
 it/src/test/resources/configuration.yaml      |   5 +
 .../spectrum/SpectrumSessionListener.java     |  17 +++
 .../DriverDeserializer.java                   |   4 +-
 .../EnvironmentDeserializer.java              |   4 +-
 .../InterpolatedBooleanDeserializer.java      |   4 +-
 .../InterpolatedDeserializer.java             |  41 ++++++
 .../InterpolatedObjectDeserializer.java       |  25 ++--
 .../InterpolatedStringDeserializer.java       |   4 +-
 .../ConfigurationInterpolator.java}           |  17 ++-
 .../EnvironmentInterpolator.java              |  11 ++
 .../interpolators/ExternalInterpolator.java   |  62 +++++++++
 .../interpolators/Interpolator.java           |  20 +++
 .../interpolators/PropertiesInterpolator.java |  11 ++
 .../giulong/spectrum/utils/Configuration.java |  31 +++++
 .../giulong/spectrum/utils/Reflections.java   |  13 ++
 .../giulong/spectrum/utils/YamlUtils.java     |  47 +++++--
 .../utils/file_providers/FileProvider.java    |   4 +-
 .../resources/yaml/configuration.default.yaml |  12 ++
 .../spectrum/SpectrumSessionListenerTest.java |  52 ++++++-
 .../InterpolatedBooleanDeserializerTest.java  |  78 -----------
 .../DriverDeserializerTest.java               |  63 +++++++--
 .../EnvironmentDeserializerTest.java          |  82 +++++++++--
 .../InterpolatedBooleanDeserializerTest.java  | 103 ++++++++++++++
 .../InterpolatedDeserializerTest.java         | 127 ++++++++++++++++++
 .../InterpolatedObjectDeserializerTest.java   |  12 +-
 .../InterpolatedStringDeserializerTest.java   |  65 +++++++--
 .../ConfigurationInterpolatorTest.java        | 103 ++++++++++++++
 .../EnvironmentInterpolatorTest.java          |  31 +++++
 .../ExternalInterpolatorTest.java             | 125 +++++++++++++++++
 .../PropertiesInterpolatorTest.java           |  31 +++++
 .../spectrum/utils/ReflectionsTest.java       |  11 ++
 .../giulong/spectrum/utils/YamlUtilsTest.java |  64 ++++++++-
 .../file_providers/FileProviderTest.java      |   2 +-
 33 files changed, 1124 insertions(+), 157 deletions(-)
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/DriverDeserializer.java (98%)
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/EnvironmentDeserializer.java (98%)
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/InterpolatedBooleanDeserializer.java (97%)
 create mode 100644 spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/InterpolatedObjectDeserializer.java (84%)
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/InterpolatedStringDeserializer.java (97%)
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/{InterpolatedDeserializer.java => interpolation/interpolators/ConfigurationInterpolator.java} (77%)
 create mode 100644 spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolator.java
 create mode 100644 spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java
 create mode 100644 spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java
 create mode 100644 spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolator.java
 delete mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializerTest.java
 rename spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/DriverDeserializerTest.java (57%)
 rename spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/EnvironmentDeserializerTest.java (50%)
 create mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializerTest.java
 create mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
 rename spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/InterpolatedObjectDeserializerTest.java (96%)
 rename spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/{ => interpolation}/InterpolatedStringDeserializerTest.java (67%)
 create mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
 create mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolatorTest.java
 create mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java
 create mode 100644 spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolatorTest.java

diff --git a/it/src/test/resources/configuration.yaml b/it/src/test/resources/configuration.yaml
index 49d6aa900..aca3003ba 100644
--- a/it/src/test/resources/configuration.yaml
+++ b/it/src/test/resources/configuration.yaml
@@ -1,3 +1,8 @@
+config:
+  interpolators:
+    environment: { }
+    properties: { }
+
 application:
   baseUrl: https://the-internet.herokuapp.com/
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java b/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java
index a2ef02b6e..6b2a7934b 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java
@@ -6,6 +6,7 @@
 
 import io.github.giulong.spectrum.types.ProjectProperties;
 import io.github.giulong.spectrum.utils.*;
+import io.github.giulong.spectrum.utils.Configuration.Config;
 import io.github.giulong.spectrum.utils.events.EventsDispatcher;
 
 import lombok.extern.slf4j.Slf4j;
@@ -21,6 +22,7 @@ public class SpectrumSessionListener implements LauncherSessionListener {
     public static final String DEFAULT_CONFIGURATION_UNIX_YAML = "yaml/configuration.default.unix.yaml";
     public static final String CONFIGURATION = "configuration";
     public static final String PROFILE_NODE = "/runtime/profiles";
+    public static final String CONFIG_NODE = "/config";
     public static final String VARS_NODE = "/vars";
 
     private final Vars vars = Vars.getInstance();
@@ -70,7 +72,9 @@ void parseConfiguration() {
                 .map(profile -> String.format("configuration-%s", profile))
                 .toList();
 
+        parseConfig(profileConfigurations);
         parseVars(profileConfigurations);
+
         yamlUtils.updateWithInternalFile(configuration, DEFAULT_CONFIGURATION_YAML);
 
         if (isUnix()) {
@@ -92,6 +96,19 @@ List<String> parseProfiles() {
                 .toList();
     }
 
+    void parseConfig(final List<String> profileConfigurations) {
+        final Config config = yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML);
+
+        if (isUnix()) {
+            yamlUtils.updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
+        }
+
+        yamlUtils.updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
+        profileConfigurations.forEach(p -> yamlUtils.updateWithClientNode(config, CONFIG_NODE, p));
+
+        configuration.setConfig(config);
+    }
+
     void parseVars(final List<String> profileConfigurations) {
         vars.putAll(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML));
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/DriverDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java
similarity index 98%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/DriverDeserializer.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java
index f45651ee1..71f1504b8 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/DriverDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java
@@ -1,4 +1,4 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static lombok.AccessLevel.PRIVATE;
 
@@ -25,7 +25,7 @@ public static DriverDeserializer getInstance() {
     @Override
     public Driver<?, ?, ?> deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException {
         final String value = jsonParser.getValueAsString();
-        final String interpolatedValue = interpolate(value, jsonParser.currentName());
+        final String interpolatedValue = interpolate(value, jsonParser);
         log.trace("Deserializing driver from value {} -> {}", value, interpolatedValue);
 
         return switch (interpolatedValue) {
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/EnvironmentDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java
similarity index 98%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/EnvironmentDeserializer.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java
index 76242991a..21e80c89d 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/EnvironmentDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java
@@ -1,4 +1,4 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static lombok.AccessLevel.PRIVATE;
 
@@ -28,7 +28,7 @@ public static EnvironmentDeserializer getInstance() {
     @Override
     public Environment deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException {
         final String value = jsonParser.getValueAsString();
-        final String interpolatedValue = interpolate(value, jsonParser.currentName());
+        final String interpolatedValue = interpolate(value, jsonParser);
         log.trace("Deserializing environment from value {} -> {}", value, interpolatedValue);
 
         return switch (interpolatedValue) {
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java
similarity index 97%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializer.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java
index f07dda87b..e1e238a5b 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java
@@ -1,4 +1,4 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static lombok.AccessLevel.PRIVATE;
 
@@ -25,6 +25,6 @@ public Boolean deserialize(final JsonParser jsonParser, final DeserializationCon
         final String value = jsonParser.getValueAsString();
         log.trace("Deserializing Boolean from value {}", value);
 
-        return Boolean.parseBoolean(interpolate(value, jsonParser.currentName()));
+        return Boolean.parseBoolean(interpolate(value, jsonParser));
     }
 }
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
new file mode 100644
index 000000000..823e1040b
--- /dev/null
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
@@ -0,0 +1,41 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
+
+import java.util.List;
+import java.util.Optional;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.Interpolator;
+import io.github.giulong.spectrum.utils.Configuration;
+import io.github.giulong.spectrum.utils.Configuration.Config;
+import io.github.giulong.spectrum.utils.Reflections;
+
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+public abstract class InterpolatedDeserializer<T> extends JsonDeserializer<T> {
+
+    private final Configuration configuration = Configuration.getInstance();
+
+    public String interpolate(final String value, final JsonParser jsonParser) {
+        final Config config = configuration.getConfig();
+
+        if (config != null) {
+            final List<Interpolator> interpolators = Reflections.getFieldsValueOf(config.getInterpolators());
+            final List<String> values = interpolators
+                    .stream()
+                    .filter(Interpolator::isEnabled)
+                    .map(i -> i.findVariableFor(value, jsonParser))
+                    .filter(Optional::isPresent)
+                    .map(Optional::get)
+                    .toList();
+
+            if (!values.isEmpty()) {
+                return values.getLast();
+            }
+        }
+
+        return value;
+    }
+}
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedObjectDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedObjectDeserializer.java
similarity index 84%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedObjectDeserializer.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedObjectDeserializer.java
index 38b8abdd1..4007dfb00 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedObjectDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedObjectDeserializer.java
@@ -1,4 +1,4 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static java.util.stream.Collectors.toMap;
 import static lombok.AccessLevel.PRIVATE;
@@ -20,6 +20,7 @@
 import io.github.giulong.spectrum.utils.Vars;
 
 import lombok.NoArgsConstructor;
+import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
@@ -48,31 +49,33 @@ public Object deserialize(final JsonParser jsonParser, final DeserializationCont
         return switch (jsonNodeType) {
             case NUMBER -> jsonNode.numberValue();
             case BOOLEAN -> jsonNode.booleanValue();
-            case STRING -> traverse(jsonNode.textValue(), currentName);
-            case OBJECT -> traverse(objectMapper.convertValue(jsonNode, Map.class), currentName);
-            case ARRAY -> traverse(objectMapper.convertValue(jsonNode, List.class), currentName);
-            default -> traverse(jsonNode, currentName);
+            case STRING -> traverse(jsonNode.textValue(), jsonParser);
+            case OBJECT -> traverse(objectMapper.convertValue(jsonNode, Map.class), jsonParser);
+            case ARRAY -> traverse(objectMapper.convertValue(jsonNode, List.class), jsonParser);
+            default -> traverse(jsonNode, jsonParser);
         };
     }
 
-    Object traverse(final Object value, final String currentName) {
+    Object traverse(final Object value, final JsonParser jsonParser) {
         return switch (value) {
             case String v -> {
                 final Matcher matcher = INT_PATTERN.matcher(v);
                 yield matcher.matches()
-                        ? interpolate(v, currentName, matcher)
-                        : InterpolatedStringDeserializer.getInstance().interpolate(v, currentName);
+                        ? interpolate(v, jsonParser, matcher)
+                        : InterpolatedStringDeserializer.getInstance().interpolate(v, jsonParser);
             }
             case Map<?, ?> m -> m
                     .entrySet()
                     .stream()
-                    .collect(toMap(Map.Entry::getKey, e -> traverse(e.getValue(), currentName)));
-            case List<?> l -> l.stream().map(e -> traverse(e, currentName)).toList();
+                    .collect(toMap(Map.Entry::getKey, e -> traverse(e.getValue(), jsonParser)));
+            case List<?> l -> l.stream().map(e -> traverse(e, jsonParser)).toList();
             default -> value;
         };
     }
 
-    int interpolate(final String value, final String currentName, final Matcher matcher) {
+    @SneakyThrows
+    int interpolate(final String value, final JsonParser jsonParser, final Matcher matcher) {
+        final String currentName = jsonParser.currentName();
         final String varName = matcher.group("varName");
         final String placeholder = matcher.group("placeholder");
         final String defaultValue = matcher.group("defaultValue");
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedStringDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java
similarity index 97%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedStringDeserializer.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java
index 7a138bd41..d43a16be4 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedStringDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java
@@ -1,4 +1,4 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static lombok.AccessLevel.PRIVATE;
 
@@ -29,7 +29,7 @@ public String deserialize(final JsonParser jsonParser, final DeserializationCont
         final String value = jsonParser.getValueAsString();
         log.trace("Deserializing String from value {}", value);
 
-        final String interpolatedValue = interpolate(value, jsonParser.currentName());
+        final String interpolatedValue = interpolate(value, jsonParser);
         return fileUtils.interpolateTimestampFrom(interpolatedValue);
     }
 }
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
similarity index 77%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedDeserializer.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
index a5a549074..6dbe64a43 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
@@ -1,22 +1,27 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
 
+import java.util.Optional;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
-import com.fasterxml.jackson.databind.JsonDeserializer;
+import com.fasterxml.jackson.core.JsonParser;
 
 import io.github.giulong.spectrum.utils.Vars;
 
+import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
-public abstract class InterpolatedDeserializer<T> extends JsonDeserializer<T> {
+public class ConfigurationInterpolator extends Interpolator {
 
     private static final Pattern PATTERN = Pattern.compile("(?<placeholder>\\$\\{(?<varName>[\\w.]+)(:-(?<defaultValue>[\\w~\\s-.:/\\\\=]*))?})");
 
     private final Vars vars = Vars.getInstance();
 
-    public String interpolate(final String value, final String currentName) {
+    @Override
+    @SneakyThrows
+    public Optional<String> findVariableFor(final String value, final JsonParser jsonParser) {
+        final String currentName = jsonParser.currentName();
         final Matcher matcher = PATTERN.matcher(value);
 
         String interpolatedValue = value;
@@ -41,11 +46,11 @@ public String interpolate(final String value, final String currentName) {
                 log.trace("Interpolated value for key '{}: {}' -> '{}'", currentName, value, interpolatedValue);
 
                 if (PATTERN.matcher(interpolatedValue).find()) {
-                    interpolatedValue = interpolate(interpolatedValue, currentName);
+                    interpolatedValue = findVariableFor(interpolatedValue, jsonParser).orElseThrow();
                 }
             }
         }
 
-        return interpolatedValue;
+        return Optional.of(interpolatedValue);
     }
 }
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolator.java
new file mode 100644
index 000000000..a3d3e9db4
--- /dev/null
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolator.java
@@ -0,0 +1,11 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import java.util.function.Function;
+
+public class EnvironmentInterpolator extends ExternalInterpolator {
+
+    @Override
+    public Function<String, String> getConsumer() {
+        return System::getenv;
+    }
+}
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java
new file mode 100644
index 000000000..e65619895
--- /dev/null
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java
@@ -0,0 +1,62 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import static java.util.stream.Collectors.joining;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.function.Function;
+
+import com.fasterxml.jackson.annotation.JsonPropertyDescription;
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonStreamContext;
+
+import lombok.Getter;
+import lombok.extern.slf4j.Slf4j;
+
+@Slf4j
+@Getter
+public abstract class ExternalInterpolator extends Interpolator {
+
+    @SuppressWarnings("unused")
+    @JsonPropertyDescription("Variable prefix")
+    private String prefix;
+
+    @SuppressWarnings("unused")
+    @JsonPropertyDescription("Variable tokens' delimiter")
+    private String delimiter;
+
+    public abstract Function<String, String> getConsumer();
+
+    @Override
+    public Optional<String> findVariableFor(final String value, final JsonParser jsonParser) {
+        final String className = getClass().getSimpleName();
+        final List<String> keyPathTokens = new ArrayList<>();
+        keyPathTokens.add(prefix);
+        getKeyPathTokens(keyPathTokens, jsonParser.getParsingContext());
+
+        final String keyPath = keyPathTokens
+                .stream()
+                .filter(Objects::nonNull)
+                .collect(joining(delimiter));
+        log.trace("{} is looking for {}", className, keyPath);
+
+        final String key = getConsumer().apply(keyPath);
+        if (key != null) {
+            log.debug("{} found {} = {}", className, keyPath, key);
+            return Optional.of(key);
+        }
+
+        return Optional.empty();
+    }
+
+    void getKeyPathTokens(final List<String> accumulator, final JsonStreamContext context) {
+        final JsonStreamContext parentContext = context.getParent();
+
+        if (parentContext != null) {
+            getKeyPathTokens(accumulator, parentContext);
+            accumulator.add(context.getCurrentName());
+        }
+    }
+}
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java
new file mode 100644
index 000000000..45a8cc479
--- /dev/null
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java
@@ -0,0 +1,20 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import java.util.Optional;
+
+import com.fasterxml.jackson.annotation.JacksonInject;
+import com.fasterxml.jackson.annotation.JsonPropertyDescription;
+import com.fasterxml.jackson.core.JsonParser;
+
+import lombok.Getter;
+
+@Getter
+public abstract class Interpolator {
+
+    @SuppressWarnings("unused")
+    @JacksonInject("enabledFromClient")
+    @JsonPropertyDescription("Whether to enable this interpolator. Injected to true by default, so no need to explicitly set it")
+    private boolean enabled;
+
+    public abstract Optional<String> findVariableFor(String value, JsonParser jsonParser);
+}
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolator.java
new file mode 100644
index 000000000..89ac41d1d
--- /dev/null
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolator.java
@@ -0,0 +1,11 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import java.util.function.Function;
+
+public class PropertiesInterpolator extends ExternalInterpolator {
+
+    @Override
+    public Function<String, String> getConsumer() {
+        return System::getProperty;
+    }
+}
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
index ca4778c09..5e82df166 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
@@ -16,6 +16,9 @@
 
 import io.github.giulong.spectrum.drivers.Driver;
 import io.github.giulong.spectrum.interfaces.JsonSchemaTypes;
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.ConfigurationInterpolator;
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.EnvironmentInterpolator;
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.PropertiesInterpolator;
 import io.github.giulong.spectrum.utils.environments.Environment;
 import io.github.giulong.spectrum.utils.events.EventsConsumer;
 import io.github.giulong.spectrum.utils.testbook.TestBook;
@@ -25,6 +28,7 @@
 import lombok.Generated;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
+import lombok.Setter;
 
 import org.openqa.selenium.chromium.ChromiumDriverLogLevel;
 import org.openqa.selenium.firefox.FirefoxDriverLogLevel;
@@ -36,6 +40,11 @@ public class Configuration {
 
     private static final Configuration INSTANCE = new Configuration();
 
+    @Setter
+    @JsonIgnore
+    @JsonPropertyDescription("Generic configuration")
+    private Config config;
+
     @JsonPropertyDescription("Common vars to interpolate other String values in the configuration")
     private Map<String, Object> vars;
 
@@ -80,6 +89,28 @@ public static Configuration getInstance() {
         return INSTANCE;
     }
 
+    @Getter
+    @Generated
+    public static class Config {
+
+        @JsonPropertyDescription("Configuration keys interpolators")
+        private Interpolators interpolators;
+
+        @Getter
+        @Generated
+        public static class Interpolators {
+
+            @JsonPropertyDescription("Environment variables interpolator")
+            private EnvironmentInterpolator environment;
+
+            @JsonPropertyDescription("Properties interpolator")
+            private PropertiesInterpolator properties;
+
+            @JsonPropertyDescription("In-place configuration file interpolator")
+            private ConfigurationInterpolator configuration;
+        }
+    }
+
     @Getter
     @Generated
     public static class Runtime {
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Reflections.java b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Reflections.java
index abc7e9e8b..7932f5b74 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Reflections.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Reflections.java
@@ -43,6 +43,19 @@ public static List<Field> getFieldsOf(Class<?> clazz, final Class<?> limit) {
         return fields;
     }
 
+    @SafeVarargs
+    public static <T> List<T> getFieldsValueOf(final Object object, final T... reified) {
+        final Class<?> clazz = object.getClass();
+        final Class<T> targetClass = getClassOf(reified);
+
+        return getFieldsOf(clazz, clazz.getSuperclass())
+                .stream()
+                .peek(f -> f.setAccessible(true))
+                .map(f -> getValueOf(f, object))
+                .map(targetClass::cast)
+                .toList();
+    }
+
     @SneakyThrows
     public static Field getField(final String fieldName, final Object object) {
         log.trace("Getting field {}.{}", object.getClass().getSimpleName(), fieldName);
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/utils/YamlUtils.java b/spectrum/src/main/java/io/github/giulong/spectrum/utils/YamlUtils.java
index 04c04a821..484a30902 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/utils/YamlUtils.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/utils/YamlUtils.java
@@ -5,6 +5,7 @@
 
 import java.time.Duration;
 import java.util.Random;
+import java.util.function.BiConsumer;
 
 import ch.qos.logback.classic.Level;
 
@@ -15,6 +16,7 @@
 
 import io.github.giulong.spectrum.drivers.Driver;
 import io.github.giulong.spectrum.internals.jackson.deserializers.*;
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.*;
 import io.github.giulong.spectrum.utils.environments.Environment;
 import io.github.giulong.spectrum.utils.file_providers.ClientFileProvider;
 import io.github.giulong.spectrum.utils.file_providers.FileProvider;
@@ -113,6 +115,14 @@ public <T> void updateWithInternalFile(final T t, final String file) {
         updateWithFile(t, file, internalFileProvider);
     }
 
+    public <T> void updateWithInternalNode(final T t, final String node, final String file) {
+        updateNode(t, node, file, internalFileProvider);
+    }
+
+    public <T> void updateWithClientNode(final T t, final String node, final String file) {
+        updateNode(t, node, file, clientFileProvider);
+    }
+
     @SneakyThrows
     public String write(final Object object) {
         return writer.writeValueAsString(object);
@@ -138,6 +148,16 @@ SimpleModule buildDynamicModuleFor(final Class<?> clazz, final String file) {
         return buildModuleFor(clazz, new DynamicDeserializer<>(clazz, file));
     }
 
+    @SneakyThrows
+    <T> T read(final ObjectReader reader, final String file, final String node) {
+        return reader.readValue(yamlMapper.readTree(classLoader.getResourceAsStream(file)).at(node));
+    }
+
+    @SneakyThrows
+    <T> T read(final ObjectReader reader, final String file) {
+        return reader.readValue(classLoader.getResourceAsStream(file));
+    }
+
     @SneakyThrows
     <T> T read(final ObjectReader reader, final String file, final Class<T> clazz) {
         return reader.readValue(classLoader.getResourceAsStream(file), clazz);
@@ -154,32 +174,37 @@ <T> T read(final FileProvider fileProvider, final String file, final Class<T> cl
     }
 
     @SneakyThrows
-    <T> T readNode(final FileProvider fileProvider, final String node, final String file, final Class<T> clazz) {
+    <T> T readNode(final FileProvider fileProvider, final String name, final String file, final Class<T> clazz) {
         final String fileFound = fileProvider.find(file);
         if (fileFound == null) {
             return null;
         }
 
-        log.debug("Reading node '{}' of file '{}' onto an instance of {}", node, fileFound, clazz.getSimpleName());
-        final JsonNode root = fileProvider
+        log.debug("Reading node '{}' of file '{}' onto an instance of {}", name, fileFound, clazz.getSimpleName());
+        final JsonNode node = fileProvider
                 .augment(yamlMapper)
-                .readTree(classLoader.getResourceAsStream(fileFound));
+                .readTree(classLoader.getResourceAsStream(fileFound))
+                .at(name);
 
-        return yamlMapper.convertValue(root.at(node), clazz);
+        return yamlMapper.convertValue(node, clazz);
+    }
+
+    <T> void updateNode(final T t, final String name, final String file, final FileProvider fileProvider) {
+        updateAndAccept(t, file, fileProvider, (fileFound, reader) -> read(reader, fileFound, name));
     }
 
-    @SneakyThrows
     <T> void updateWithFile(final T t, final String file, final FileProvider fileProvider) {
+        updateAndAccept(t, file, fileProvider, (fileFound, reader) -> read(reader, fileFound));
+    }
+
+    <T> void updateAndAccept(final T t, final String file, final FileProvider fileProvider, final BiConsumer<String, ObjectReader> callback) {
         final String fileFound = fileProvider.find(file);
         if (fileFound == null) {
-            log.warn("File not found. Skipping update of the instance of {}", t.getClass().getSimpleName());
+            log.debug("File not found. Skipping update of the instance of {}", t.getClass().getSimpleName());
             return;
         }
 
         log.debug("Updating the instance of {} with file '{}'", t.getClass().getSimpleName(), fileFound);
-        fileProvider
-                .augment(yamlMapper)
-                .withValueToUpdate(t)
-                .readValue(classLoader.getResourceAsStream(fileFound));
+        callback.accept(fileFound, fileProvider.augment(yamlMapper).withValueToUpdate(t));
     }
 }
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/utils/file_providers/FileProvider.java b/spectrum/src/main/java/io/github/giulong/spectrum/utils/file_providers/FileProvider.java
index 0b5b112be..4364cc861 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/utils/file_providers/FileProvider.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/utils/file_providers/FileProvider.java
@@ -9,9 +9,9 @@
 public interface FileProvider {
     default ObjectReader augment(final ObjectMapper mapper) {
         return mapper
+                .setInjectableValues(getInjectableValues())
                 .reader()
-                .withView(getViews())
-                .with(getInjectableValues());
+                .withView(getViews());
     }
 
     Class<? extends Views> getViews();
diff --git a/spectrum/src/main/resources/yaml/configuration.default.yaml b/spectrum/src/main/resources/yaml/configuration.default.yaml
index 052f1ff4d..c19f88147 100644
--- a/spectrum/src/main/resources/yaml/configuration.default.yaml
+++ b/spectrum/src/main/resources/yaml/configuration.default.yaml
@@ -1,3 +1,15 @@
+# Generic configuration
+config:
+  interpolators: # Configuration keys interpolators
+    environment: # Environment variables interpolator
+      prefix: spectrum # Variable prefix
+      delimiter: . # Variable tokens' delimiter
+    properties: # Properties interpolator
+      prefix: spectrum # Variable prefix
+      delimiter: . # Variable tokens' delimiter
+    configuration: # In-place configuration file interpolator
+      enabled: true
+
 # Common vars to interpolate other String values in the configuration
 vars:
   downloadsFolder: ${user.dir}\target\downloads # Path, as you can see below, where to save downloaded files
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java
index cc9f43789..a8c97c331 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java
@@ -11,6 +11,7 @@
 
 import io.github.giulong.spectrum.types.ProjectProperties;
 import io.github.giulong.spectrum.utils.*;
+import io.github.giulong.spectrum.utils.Configuration.Config;
 import io.github.giulong.spectrum.utils.environments.Environment;
 import io.github.giulong.spectrum.utils.events.EventsDispatcher;
 import io.github.giulong.spectrum.utils.testbook.TestBook;
@@ -67,6 +68,9 @@ class SpectrumSessionListenerTest {
     @Mock
     private TestBook testBook;
 
+    @Mock
+    private Config config;
+
     @Mock
     private Summary summary;
 
@@ -124,6 +128,9 @@ void launcherSessionOpened() {
         when(yamlUtils.readInternal("properties.yaml", ProjectProperties.class)).thenReturn(projectProperties);
         when(freeMarkerWrapper.interpolate(banner, projectProperties)).thenReturn(interpolatedBanner);
 
+        // parseConfig
+        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
+
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn(profile);
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
@@ -183,6 +190,9 @@ void parseConfigurationNoProfile() {
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn("");
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
 
+        // parseConfig
+        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
+
         // parseVars
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
 
@@ -204,6 +214,9 @@ void parseConfiguration() {
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn(profile);
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
 
+        // parseConfig
+        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
+
         // parseVars
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
 
@@ -222,10 +235,13 @@ void parseConfigurationUnix() {
 
         System.setProperty("os.name", "nix");
 
-        // parseProfile
+        // parseProfiles
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn(profile);
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
 
+        // parseConfig
+        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
+
         // parseVars
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_UNIX_YAML)).thenReturn(Map.of("one", "one"));
@@ -258,6 +274,38 @@ static Stream<Arguments> profilesValuesProvider() {
                 arguments(null, " ,,default-profile,another", List.of("default-profile", "another")));
     }
 
+    @Test
+    @DisplayName("parseConfig should parse the config node read from the configuration yaml files")
+    void parseConfig() {
+        final String profileConfiguration = "profileConfiguration";
+
+        System.setProperty("os.name", "Win");
+
+        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
+
+        spectrumSessionListener.parseConfig(List.of(profileConfiguration));
+
+        verify(yamlUtils, never()).updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
+        verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
+        verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, profileConfiguration);
+    }
+
+    @Test
+    @DisplayName("parseConfig should parse the also the config node read from the internal configuration.default.unix.yaml")
+    void parseConfigUnix() {
+        final String profileConfiguration = "profileConfiguration";
+
+        System.setProperty("os.name", "nix");
+
+        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
+
+        spectrumSessionListener.parseConfig(List.of(profileConfiguration));
+
+        verify(yamlUtils).updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
+        verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
+        verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, profileConfiguration);
+    }
+
     @DisplayName("parseVars should put in the VARS map all the variables read from the configuration yaml files")
     @ParameterizedTest
     @MethodSource("varsValuesProvider")
@@ -272,6 +320,8 @@ void parseVars(final Map<String, String> defaultVars, final Map<String, String>
 
         spectrumSessionListener.parseVars(List.of(profileConfiguration));
         assertEquals(expected, Vars.getInstance());
+
+        verify(yamlUtils, never()).updateWithInternalNode(config, VARS_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
     }
 
     @DisplayName("parseVars should put in the VARS map also those read from the internal configuration.default.unix.yaml")
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializerTest.java
deleted file mode 100644
index 9ebe77493..000000000
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedBooleanDeserializerTest.java
+++ /dev/null
@@ -1,78 +0,0 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
-
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertSame;
-import static org.junit.jupiter.params.provider.Arguments.arguments;
-import static org.mockito.Mockito.when;
-
-import java.io.IOException;
-import java.util.stream.Stream;
-
-import com.fasterxml.jackson.core.JsonParser;
-import com.fasterxml.jackson.databind.DeserializationContext;
-
-import io.github.giulong.spectrum.utils.Vars;
-
-import org.junit.jupiter.api.AfterAll;
-import org.junit.jupiter.api.BeforeAll;
-import org.junit.jupiter.api.DisplayName;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.params.ParameterizedTest;
-import org.junit.jupiter.params.provider.Arguments;
-import org.junit.jupiter.params.provider.MethodSource;
-import org.mockito.InjectMocks;
-import org.mockito.Mock;
-
-class InterpolatedBooleanDeserializerTest {
-
-    @Mock
-    private JsonParser jsonParser;
-
-    @Mock
-    private DeserializationContext deserializationContext;
-
-    @InjectMocks
-    private InterpolatedBooleanDeserializer interpolatedBooleanDeserializer;
-
-    private static final String VAR_IN_ENV = "varInEnv";
-
-    @BeforeAll
-    public static void beforeAll() {
-        Vars.getInstance().put("varInEnv", VAR_IN_ENV);
-    }
-
-    @AfterAll
-    public static void afterAll() {
-        Vars.getInstance().clear();
-    }
-
-    @Test
-    @DisplayName("getInstance should return the singleton")
-    void getInstance() {
-        //noinspection EqualsWithItself
-        assertSame(InterpolatedBooleanDeserializer.getInstance(), InterpolatedBooleanDeserializer.getInstance());
-    }
-
-    @DisplayName("deserialize should delegate to the parent method passing the string value")
-    @ParameterizedTest(name = "with value {0} we expect {1}")
-    @MethodSource("valuesProvider")
-    void deserialize(final String value, final boolean expected) throws IOException {
-        when(jsonParser.getValueAsString()).thenReturn(value);
-        when(jsonParser.currentName()).thenReturn("key");
-
-        assertEquals(expected, interpolatedBooleanDeserializer.deserialize(jsonParser, deserializationContext));
-    }
-
-    static Stream<Arguments> valuesProvider() {
-        return Stream.of(
-                arguments("true", true),
-                arguments("false", false),
-                arguments("${not.set:-true}", true),
-                arguments("${notSet:-true}", true),
-                arguments("${notSet:-}", false),
-                arguments("${varInEnv:-true}", false),
-                arguments("${varInEnv}", false),
-                arguments("${not.set}", false),
-                arguments("${notSet}", false));
-    }
-}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/DriverDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializerTest.java
similarity index 57%
rename from spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/DriverDeserializerTest.java
rename to spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializerTest.java
index b132ad934..4da6361d3 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/DriverDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializerTest.java
@@ -1,18 +1,28 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static org.junit.jupiter.api.Assertions.*;
 import static org.junit.jupiter.params.provider.Arguments.arguments;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.mockStatic;
 import static org.mockito.Mockito.when;
 
 import java.io.IOException;
+import java.util.List;
+import java.util.Optional;
 import java.util.stream.Stream;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.databind.DeserializationContext;
 
 import io.github.giulong.spectrum.drivers.*;
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.Interpolator;
+import io.github.giulong.spectrum.utils.Configuration;
+import io.github.giulong.spectrum.utils.Configuration.Config;
+import io.github.giulong.spectrum.utils.Configuration.Config.Interpolators;
+import io.github.giulong.spectrum.utils.Reflections;
 
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -20,9 +30,24 @@
 import org.junit.jupiter.params.provider.MethodSource;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.MockedStatic;
 
 class DriverDeserializerTest {
 
+    private MockedStatic<Reflections> reflectionsMockedStatic;
+
+    @Mock
+    private Configuration configuration;
+
+    @Mock
+    private Config config;
+
+    @Mock
+    private Interpolators interpolators;
+
+    @Mock
+    private Interpolator interpolator;
+
     @Mock
     private JsonParser jsonParser;
 
@@ -30,7 +55,19 @@ class DriverDeserializerTest {
     private DeserializationContext deserializationContext;
 
     @InjectMocks
-    private DriverDeserializer driverDeserializer;
+    private DriverDeserializer deserializer;
+
+    @BeforeEach
+    void beforeEach() {
+        Reflections.setField("configuration", deserializer, configuration);
+
+        reflectionsMockedStatic = mockStatic(Reflections.class);
+    }
+
+    @AfterEach
+    void afterEach() {
+        reflectionsMockedStatic.close();
+    }
 
     @Test
     @DisplayName("getInstance should return the singleton")
@@ -43,26 +80,27 @@ void getInstance() {
     @ParameterizedTest(name = "with value {0} we expect {1}")
     @MethodSource("valuesProvider")
     void deserialize(final String value, final Driver<?, ?, ?> expected) throws IOException {
+        interpolateStubsFor(value);
+
         when(jsonParser.getValueAsString()).thenReturn(value);
-        when(jsonParser.currentName()).thenReturn("key");
 
-        assertInstanceOf(expected.getClass(), driverDeserializer.deserialize(jsonParser, deserializationContext));
+        assertInstanceOf(expected.getClass(), deserializer.deserialize(jsonParser, deserializationContext));
     }
 
     @Test
     @DisplayName("deserialize should throw an exception if the provided key is not a valid driver name")
     void deserializeNotExisting() throws IOException {
-        String notValidDriver = "notValidDriver";
+        final String notValidDriver = "notValidDriver";
+
+        interpolateStubsFor(notValidDriver);
         when(jsonParser.getValueAsString()).thenReturn(notValidDriver);
-        when(jsonParser.currentName()).thenReturn("key");
 
-        Exception exception = assertThrows(IllegalArgumentException.class, () -> driverDeserializer.deserialize(jsonParser, deserializationContext));
+        Exception exception = assertThrows(IllegalArgumentException.class, () -> deserializer.deserialize(jsonParser, deserializationContext));
         assertEquals("Value '" + notValidDriver + "' is not a valid driver!", exception.getMessage());
     }
 
     static Stream<Arguments> valuesProvider() {
         return Stream.of(
-                arguments("${justToTestInterpolation:-chrome}", mock(Chrome.class)),
                 arguments("chrome", mock(Chrome.class)),
                 arguments("firefox", mock(Firefox.class)),
                 arguments("edge", mock(Edge.class)),
@@ -74,4 +112,13 @@ static Stream<Arguments> valuesProvider() {
                 arguments("mac2", mock(Mac2.class)),
                 arguments("appiumGeneric", mock(AppiumGeneric.class)));
     }
+
+    private void interpolateStubsFor(final String value) {
+        when(configuration.getConfig()).thenReturn(config);
+        when(config.getInterpolators()).thenReturn(interpolators);
+        when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator));
+        when(interpolator.isEnabled()).thenReturn(true);
+
+        when(interpolator.findVariableFor(value, jsonParser)).thenReturn(Optional.of(value));
+    }
 }
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/EnvironmentDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializerTest.java
similarity index 50%
rename from spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/EnvironmentDeserializerTest.java
rename to spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializerTest.java
index e1cfd0db5..1a874947e 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/EnvironmentDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializerTest.java
@@ -1,21 +1,35 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
-import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertInstanceOf;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.params.provider.Arguments.arguments;
 import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.mockStatic;
+import static org.mockito.Mockito.verifyNoInteractions;
 import static org.mockito.Mockito.when;
 
 import java.io.IOException;
+import java.util.List;
+import java.util.Optional;
 import java.util.stream.Stream;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.databind.DeserializationContext;
 
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.Interpolator;
+import io.github.giulong.spectrum.utils.Configuration;
+import io.github.giulong.spectrum.utils.Configuration.Config;
+import io.github.giulong.spectrum.utils.Configuration.Config.Interpolators;
+import io.github.giulong.spectrum.utils.Reflections;
 import io.github.giulong.spectrum.utils.environments.AppiumEnvironment;
 import io.github.giulong.spectrum.utils.environments.Environment;
 import io.github.giulong.spectrum.utils.environments.GridEnvironment;
 import io.github.giulong.spectrum.utils.environments.LocalEnvironment;
 
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
@@ -23,9 +37,24 @@
 import org.junit.jupiter.params.provider.MethodSource;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.MockedStatic;
 
 class EnvironmentDeserializerTest {
 
+    private MockedStatic<Reflections> reflectionsMockedStatic;
+
+    @Mock
+    private Configuration configuration;
+
+    @Mock
+    private Config config;
+
+    @Mock
+    private Interpolators interpolators;
+
+    @Mock
+    private Interpolator interpolator;
+
     @Mock
     private JsonParser jsonParser;
 
@@ -33,7 +62,19 @@ class EnvironmentDeserializerTest {
     private DeserializationContext deserializationContext;
 
     @InjectMocks
-    private EnvironmentDeserializer environmentDeserializer;
+    private EnvironmentDeserializer deserializer;
+
+    @BeforeEach
+    void beforeEach() {
+        Reflections.setField("configuration", deserializer, configuration);
+
+        reflectionsMockedStatic = mockStatic(Reflections.class);
+    }
+
+    @AfterEach
+    void afterEach() {
+        reflectionsMockedStatic.close();
+    }
 
     @Test
     @DisplayName("getInstance should return the singleton")
@@ -46,28 +87,41 @@ void getInstance() {
     @ParameterizedTest(name = "with value {0} we expect {1}")
     @MethodSource("valuesProvider")
     void deserialize(final String value, final Environment expected) throws IOException {
+        interpolateStubsFor(value);
+
         when(jsonParser.getValueAsString()).thenReturn(value);
-        when(jsonParser.currentName()).thenReturn("key");
 
-        assertInstanceOf(expected.getClass(), environmentDeserializer.deserialize(jsonParser, deserializationContext));
+        assertInstanceOf(expected.getClass(), deserializer.deserialize(jsonParser, deserializationContext));
+    }
+
+    static Stream<Arguments> valuesProvider() {
+        return Stream.of(
+                arguments("local", mock(LocalEnvironment.class)),
+                arguments("grid", mock(GridEnvironment.class)),
+                arguments("appium", mock(AppiumEnvironment.class)));
     }
 
     @Test
     @DisplayName("deserialize should throw an exception if the provided key is not a valid environment name")
     void deserializeNotExisting() throws IOException {
-        String notValidEnvironment = "notValidEnvironment";
+        final String notValidEnvironment = "notValidEnvironment";
+
+        interpolateStubsFor(notValidEnvironment);
+
         when(jsonParser.getValueAsString()).thenReturn(notValidEnvironment);
-        when(jsonParser.currentName()).thenReturn("key");
 
-        Exception exception = assertThrows(IllegalArgumentException.class, () -> environmentDeserializer.deserialize(jsonParser, deserializationContext));
+        final Exception exception = assertThrows(IllegalArgumentException.class, () -> deserializer.deserialize(jsonParser, deserializationContext));
         assertEquals("Value '" + notValidEnvironment + "' is not a valid environment!", exception.getMessage());
+
+        verifyNoInteractions(deserializationContext);
     }
 
-    static Stream<Arguments> valuesProvider() {
-        return Stream.of(
-                arguments("${justToTestInterpolation:-local}", mock(LocalEnvironment.class)),
-                arguments("local", mock(LocalEnvironment.class)),
-                arguments("grid", mock(GridEnvironment.class)),
-                arguments("appium", mock(AppiumEnvironment.class)));
+    private void interpolateStubsFor(final String value) {
+        when(configuration.getConfig()).thenReturn(config);
+        when(config.getInterpolators()).thenReturn(interpolators);
+        when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator));
+        when(interpolator.isEnabled()).thenReturn(true);
+
+        when(interpolator.findVariableFor(value, jsonParser)).thenReturn(Optional.of(value));
     }
 }
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializerTest.java
new file mode 100644
index 000000000..10da8fdab
--- /dev/null
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializerTest.java
@@ -0,0 +1,103 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.params.provider.Arguments.arguments;
+import static org.mockito.Mockito.mockStatic;
+import static org.mockito.Mockito.when;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Optional;
+import java.util.stream.Stream;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.Interpolator;
+import io.github.giulong.spectrum.utils.Configuration;
+import io.github.giulong.spectrum.utils.Configuration.Config;
+import io.github.giulong.spectrum.utils.Configuration.Config.Interpolators;
+import io.github.giulong.spectrum.utils.Reflections;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockedStatic;
+
+class InterpolatedBooleanDeserializerTest {
+
+    private MockedStatic<Reflections> reflectionsMockedStatic;
+
+    @Mock
+    private Configuration configuration;
+
+    @Mock
+    private Config config;
+
+    @Mock
+    private Interpolators interpolators;
+
+    @Mock
+    private Interpolator interpolator;
+
+    @Mock
+    private JsonParser jsonParser;
+
+    @Mock
+    private DeserializationContext deserializationContext;
+
+    @InjectMocks
+    private InterpolatedBooleanDeserializer deserializer;
+
+    @BeforeEach
+    void beforeEach() {
+        Reflections.setField("configuration", deserializer, configuration);
+
+        reflectionsMockedStatic = mockStatic(Reflections.class);
+    }
+
+    @AfterEach
+    void afterEach() {
+        reflectionsMockedStatic.close();
+    }
+
+    @Test
+    @DisplayName("getInstance should return the singleton")
+    void getInstance() {
+        //noinspection EqualsWithItself
+        assertSame(InterpolatedBooleanDeserializer.getInstance(), InterpolatedBooleanDeserializer.getInstance());
+    }
+
+    @DisplayName("deserialize should delegate to the parent method passing the string value")
+    @ParameterizedTest(name = "with value {0} we expect {1}")
+    @MethodSource("valuesProvider")
+    void deserialize(final String value, final boolean expected) throws IOException {
+        interpolateStubsFor(value);
+
+        when(jsonParser.getValueAsString()).thenReturn(value);
+
+        assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext));
+    }
+
+    static Stream<Arguments> valuesProvider() {
+        return Stream.of(
+                arguments("true", true),
+                arguments("false", false));
+    }
+
+    private void interpolateStubsFor(final String value) {
+        when(configuration.getConfig()).thenReturn(config);
+        when(config.getInterpolators()).thenReturn(interpolators);
+        when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator));
+        when(interpolator.isEnabled()).thenReturn(true);
+
+        when(interpolator.findVariableFor(value, jsonParser)).thenReturn(Optional.of(value));
+    }
+}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
new file mode 100644
index 000000000..701de10ac
--- /dev/null
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
@@ -0,0 +1,127 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.mockStatic;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import java.util.List;
+import java.util.Optional;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.databind.DeserializationContext;
+
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.Interpolator;
+import io.github.giulong.spectrum.utils.Configuration;
+import io.github.giulong.spectrum.utils.Configuration.Config;
+import io.github.giulong.spectrum.utils.Configuration.Config.Interpolators;
+import io.github.giulong.spectrum.utils.Reflections;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.MockedStatic;
+
+class InterpolatedDeserializerTest {
+
+    private final String value = "value";
+
+    private MockedStatic<Reflections> reflectionsMockedStatic;
+
+    @Mock
+    private Configuration configuration;
+
+    @Mock
+    private Config config;
+
+    @Mock
+    private Interpolators interpolators;
+
+    @Mock
+    private Interpolator interpolator1;
+
+    @Mock
+    private Interpolator interpolator2;
+
+    @Mock
+    private Interpolator interpolator3;
+
+    @Mock
+    private Interpolator interpolator4;
+
+    @Mock
+    private JsonParser jsonParser;
+
+    @InjectMocks
+    private DummyInterpolatedDeserializer deserializer;
+
+    @BeforeEach
+    void beforeEach() {
+        Reflections.setField("configuration", deserializer, configuration);
+
+        reflectionsMockedStatic = mockStatic(Reflections.class);
+    }
+
+    @AfterEach
+    void afterEach() {
+        reflectionsMockedStatic.close();
+    }
+
+    @Test
+    @DisplayName("interpolate should just return the provided value when config is null")
+    void interpolateNoConfig() {
+        when(configuration.getConfig()).thenReturn(null);
+
+        assertEquals(value, deserializer.interpolate(value, jsonParser));
+    }
+
+    @Test
+    @DisplayName("interpolate should return the last interpolated value of the interpolators which found the key")
+    void interpolate() {
+        final String interpolatedValue1 = "interpolatedValue1";
+        final String interpolatedValue2 = "interpolatedValue2";
+
+        when(configuration.getConfig()).thenReturn(config);
+        when(config.getInterpolators()).thenReturn(interpolators);
+        when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator1, interpolator2, interpolator3, interpolator4));
+        when(interpolator1.isEnabled()).thenReturn(false);
+        when(interpolator2.isEnabled()).thenReturn(true);
+        when(interpolator3.isEnabled()).thenReturn(true);
+        when(interpolator4.isEnabled()).thenReturn(true);
+
+        when(interpolator2.findVariableFor(value, jsonParser)).thenReturn(Optional.empty());
+        when(interpolator3.findVariableFor(value, jsonParser)).thenReturn(Optional.of(interpolatedValue1));
+        when(interpolator4.findVariableFor(value, jsonParser)).thenReturn(Optional.of(interpolatedValue2));
+
+        assertEquals(interpolatedValue2, deserializer.interpolate(value, jsonParser));
+
+        verifyNoMoreInteractions(interpolator1);
+    }
+
+    @Test
+    @DisplayName("interpolate should return the provided value when no interpolators found the key")
+    void interpolateEmpty() {
+        when(configuration.getConfig()).thenReturn(config);
+        when(config.getInterpolators()).thenReturn(interpolators);
+        when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator1, interpolator2));
+        when(interpolator1.isEnabled()).thenReturn(false);
+        when(interpolator2.isEnabled()).thenReturn(true);
+
+        when(interpolator2.findVariableFor(value, jsonParser)).thenReturn(Optional.empty());
+
+        assertEquals(value, deserializer.interpolate(value, jsonParser));
+
+        verifyNoMoreInteractions(interpolator1);
+    }
+
+    private static final class DummyInterpolatedDeserializer extends InterpolatedDeserializer<String> {
+
+        @Override
+        public String deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) {
+            return "";
+        }
+    }
+}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedObjectDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedObjectDeserializerTest.java
similarity index 96%
rename from spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedObjectDeserializerTest.java
rename to spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedObjectDeserializerTest.java
index b052189dc..518038a4f 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedObjectDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedObjectDeserializerTest.java
@@ -1,4 +1,4 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static com.fasterxml.jackson.databind.node.JsonNodeType.*;
 import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
@@ -98,7 +98,7 @@ void deserializeStrings() throws IOException {
         when(jsonNode.getNodeType()).thenReturn(STRING);
         when(jsonNode.textValue()).thenReturn(value);
         when(InterpolatedStringDeserializer.getInstance()).thenReturn(interpolatedStringDeserializer);
-        when(interpolatedStringDeserializer.interpolate(value, currentName)).thenReturn(expected);
+        when(interpolatedStringDeserializer.interpolate(value, jsonParser)).thenReturn(expected);
 
         assertEquals(expected, interpolatedObjectDeserializer.deserialize(jsonParser, deserializationContext));
     }
@@ -149,7 +149,7 @@ void deserializeMap() throws IOException {
 
         when(objectMapper.convertValue(jsonNode, Map.class)).thenReturn(map);
         when(InterpolatedStringDeserializer.getInstance()).thenReturn(interpolatedStringDeserializer);
-        when(interpolatedStringDeserializer.interpolate(value, currentName)).thenReturn(interpolatedValue);
+        when(interpolatedStringDeserializer.interpolate(value, jsonParser)).thenReturn(interpolatedValue);
 
         assertEquals(interpolatedMap, interpolatedObjectDeserializer.deserialize(jsonParser, deserializationContext));
     }
@@ -178,7 +178,7 @@ void deserializeMapWithNestedMapsAndLists() throws IOException {
 
         when(objectMapper.convertValue(jsonNode, Map.class)).thenReturn(map);
         when(InterpolatedStringDeserializer.getInstance()).thenReturn(interpolatedStringDeserializer);
-        when(interpolatedStringDeserializer.interpolate(value, currentName)).thenReturn(interpolatedValue);
+        when(interpolatedStringDeserializer.interpolate(value, jsonParser)).thenReturn(interpolatedValue);
 
         assertEquals(interpolatedMap, interpolatedObjectDeserializer.deserialize(jsonParser, deserializationContext));
     }
@@ -199,7 +199,7 @@ void deserializeList() throws IOException {
 
         when(objectMapper.convertValue(jsonNode, List.class)).thenReturn(list);
         when(InterpolatedStringDeserializer.getInstance()).thenReturn(interpolatedStringDeserializer);
-        when(interpolatedStringDeserializer.interpolate(value, currentName)).thenReturn(interpolatedValue);
+        when(interpolatedStringDeserializer.interpolate(value, jsonParser)).thenReturn(interpolatedValue);
 
         assertEquals(interpolatedList, interpolatedObjectDeserializer.deserialize(jsonParser, deserializationContext));
     }
@@ -226,7 +226,7 @@ void deserializeListWithNestedMapsAndLists() throws IOException {
 
         when(objectMapper.convertValue(jsonNode, List.class)).thenReturn(list);
         when(InterpolatedStringDeserializer.getInstance()).thenReturn(interpolatedStringDeserializer);
-        when(interpolatedStringDeserializer.interpolate(value, currentName)).thenReturn(interpolatedValue);
+        when(interpolatedStringDeserializer.interpolate(value, jsonParser)).thenReturn(interpolatedValue);
 
         assertEquals(interpolatedList, interpolatedObjectDeserializer.deserialize(jsonParser, deserializationContext));
     }
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedStringDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java
similarity index 67%
rename from spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedStringDeserializerTest.java
rename to spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java
index 91fb83149..c459f8927 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/InterpolatedStringDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java
@@ -1,18 +1,26 @@
-package io.github.giulong.spectrum.internals.jackson.deserializers;
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
 import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.matchesPattern;
 import static org.junit.jupiter.api.Assertions.*;
 import static org.junit.jupiter.params.provider.Arguments.arguments;
+import static org.mockito.Mockito.mockStatic;
 import static org.mockito.Mockito.when;
 
 import java.io.IOException;
+import java.util.List;
+import java.util.Optional;
 import java.util.stream.Stream;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.databind.DeserializationContext;
 
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.Interpolator;
+import io.github.giulong.spectrum.utils.Configuration;
+import io.github.giulong.spectrum.utils.Configuration.Config;
+import io.github.giulong.spectrum.utils.Configuration.Config.Interpolators;
+import io.github.giulong.spectrum.utils.Reflections;
 import io.github.giulong.spectrum.utils.Vars;
 
 import org.junit.jupiter.api.*;
@@ -21,11 +29,27 @@
 import org.junit.jupiter.params.provider.MethodSource;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
+import org.mockito.MockedStatic;
 
+@Disabled
 class InterpolatedStringDeserializerTest {
 
     private static final String VAR_IN_ENV = "varInEnv";
 
+    private MockedStatic<Reflections> reflectionsMockedStatic;
+
+    @Mock
+    private Configuration configuration;
+
+    @Mock
+    private Config config;
+
+    @Mock
+    private Interpolators interpolators;
+
+    @Mock
+    private Interpolator interpolator;
+
     @Mock
     private JsonParser jsonParser;
 
@@ -33,13 +57,25 @@ class InterpolatedStringDeserializerTest {
     private DeserializationContext deserializationContext;
 
     @InjectMocks
-    private InterpolatedStringDeserializer interpolatedStringDeserializer;
+    private InterpolatedStringDeserializer deserializer;
 
     @BeforeAll
     public static void beforeAll() {
         Vars.getInstance().put("varInEnv", VAR_IN_ENV);
     }
 
+    @BeforeEach
+    void beforeEach() {
+        Reflections.setField("configuration", deserializer, configuration);
+
+        reflectionsMockedStatic = mockStatic(Reflections.class);
+    }
+
+    @AfterEach
+    void afterEach() {
+        reflectionsMockedStatic.close();
+    }
+
     @AfterAll
     public static void afterAll() {
         Vars.getInstance().clear();
@@ -56,10 +92,11 @@ void getInstance() {
     @ParameterizedTest(name = "with value {0} we expect {1}")
     @MethodSource("valuesProvider")
     void deserialize(final String value, final String expected) throws IOException {
+        interpolateStubsFor(value);
+
         when(jsonParser.getValueAsString()).thenReturn(value);
-        when(jsonParser.currentName()).thenReturn("not important");
 
-        assertEquals(expected, interpolatedStringDeserializer.deserialize(jsonParser, deserializationContext));
+        assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext));
     }
 
     static Stream<Arguments> valuesProvider() {
@@ -89,10 +126,10 @@ static Stream<Arguments> valuesProvider() {
     void deserializeTimestamp() throws IOException {
         final String value = "value-${timestamp}";
 
+        interpolateStubsFor(value);
         when(jsonParser.getValueAsString()).thenReturn(value);
-        when(jsonParser.currentName()).thenReturn("not important");
 
-        assertThat(interpolatedStringDeserializer.deserialize(jsonParser, deserializationContext), matchesPattern("value-[0-9]{2}-[0-9]{2}-[0-9]{4}_[0-9]{2}-[0-9]{2}-[0-9]{2}"));
+        assertThat(deserializer.deserialize(jsonParser, deserializationContext), matchesPattern("value-[0-9]{2}-[0-9]{2}-[0-9]{4}_[0-9]{2}-[0-9]{2}-[0-9]{2}"));
     }
 
     @Test
@@ -102,11 +139,10 @@ void deserializeFromSystemProperty() throws Exception {
         System.setProperty("systemProperty", expected);
 
         when(jsonParser.getValueAsString()).thenReturn("${systemProperty:-local}");
-        when(jsonParser.currentName()).thenReturn("not important");
 
         // We set the "systemProperty" env var with a random value just to check the precedence: system property wins
         withEnvironmentVariable("systemProperty", "SOME VALUE")
-                .execute(() -> assertEquals(expected, interpolatedStringDeserializer.deserialize(jsonParser, deserializationContext)));
+                .execute(() -> assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext)));
 
         System.clearProperty("systemProperty");
     }
@@ -116,9 +152,18 @@ void deserializeFromSystemProperty() throws Exception {
     void deserializeFromEnvVariables() throws Exception {
         final String expected = "expected";
 
+        interpolateStubsFor(expected);
         when(jsonParser.getValueAsString()).thenReturn("${envVar:-local}");
-        when(jsonParser.currentName()).thenReturn("not important");
 
-        withEnvironmentVariable("envVar", expected).execute(() -> assertEquals(expected, interpolatedStringDeserializer.deserialize(jsonParser, deserializationContext)));
+        withEnvironmentVariable("envVar", expected).execute(() -> assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext)));
+    }
+
+    private void interpolateStubsFor(final String value) {
+        when(configuration.getConfig()).thenReturn(config);
+        when(config.getInterpolators()).thenReturn(interpolators);
+        when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator));
+        when(interpolator.isEnabled()).thenReturn(true);
+
+        when(interpolator.findVariableFor(value, jsonParser)).thenReturn(Optional.of(value));
     }
 }
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
new file mode 100644
index 000000000..33b3ed38c
--- /dev/null
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
@@ -0,0 +1,103 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.params.provider.Arguments.arguments;
+import static org.mockito.Mockito.when;
+
+import java.io.IOException;
+import java.util.Optional;
+import java.util.stream.Stream;
+
+import com.fasterxml.jackson.core.JsonParser;
+
+import io.github.giulong.spectrum.utils.Vars;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+
+class ConfigurationInterpolatorTest {
+
+    private static final String VAR_IN_ENV = "varInEnv";
+
+    private final String currentName = "currentName";
+
+    @Mock
+    private JsonParser jsonParser;
+
+    @InjectMocks
+    private ConfigurationInterpolator interpolator;
+
+    @BeforeAll
+    public static void beforeAll() {
+        Vars.getInstance().put("varInEnv", VAR_IN_ENV);
+    }
+
+    @AfterAll
+    public static void afterAll() {
+        Vars.getInstance().clear();
+    }
+
+    @DisplayName("findVariableFor should find the right value")
+    @ParameterizedTest(name = "with value {0} we expect {1}")
+    @MethodSource("valuesProvider")
+    void deserialize(final String value, final String expected) throws IOException {
+        when(jsonParser.currentName()).thenReturn(currentName);
+
+        assertEquals(Optional.of(expected), interpolator.findVariableFor(value, jsonParser));
+    }
+
+    static Stream<Arguments> valuesProvider() {
+        return Stream.of(
+                arguments("value", "value"),
+                arguments("${not.set:-_-}", "_-"),
+                arguments("${not.set:-- -}", "- -"),
+                arguments("${not.set:--\t-}", "-\t-"),
+                arguments("${not.set:-a b }", "a b "),
+                arguments("${not.set:-local}", "local"),
+                arguments("${notSet:-local}", "local"),
+                arguments("${notSet:-local}-something_else-${varInEnv}", "local-something_else-" + VAR_IN_ENV),
+                arguments("${notSet:-${varInEnv:-local}}-nested", VAR_IN_ENV + "-nested"),
+                arguments("${notSet:-${varInEnv:-local}}-nested-${varInEnv}", VAR_IN_ENV + "-nested-" + VAR_IN_ENV),
+                arguments("${notSet:-local.dots}", "local.dots"),
+                arguments("${notSet:---key=value}", "--key=value"),
+                arguments("${notSet:-}", ""),
+                arguments("${varInEnv:-local}", VAR_IN_ENV),
+                arguments("${varInEnv}", VAR_IN_ENV),
+                arguments("${varInEnv:-~/local}", VAR_IN_ENV),
+                arguments("${not.set}", "${not.set}"),
+                arguments("${notSet}", "${notSet}"));
+    }
+
+    @Test
+    @DisplayName("findVariableFor should consider system properties")
+    void deserializeFromSystemProperty() throws Exception {
+        final String expected = "expected";
+
+        System.setProperty("systemProperty", expected);
+        when(jsonParser.currentName()).thenReturn(currentName);
+
+        // We set the "systemProperty" env var with a random value just to check the precedence: system property wins
+        withEnvironmentVariable("systemProperty", "SOME VALUE")
+                .execute(() -> assertEquals(Optional.of(expected), interpolator.findVariableFor("${systemProperty:-local}", jsonParser)));
+
+        System.clearProperty("systemProperty");
+    }
+
+    @Test
+    @DisplayName("findVariableFor should consider env variables")
+    void deserializeFromEnvVariables() throws Exception {
+        final String expected = "expected";
+
+        when(jsonParser.currentName()).thenReturn(currentName);
+
+        withEnvironmentVariable("envVar", expected).execute(() -> assertEquals(Optional.of(expected), interpolator.findVariableFor("${envVar:-local}", jsonParser)));
+    }
+}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolatorTest.java
new file mode 100644
index 000000000..fe842e9eb
--- /dev/null
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/EnvironmentInterpolatorTest.java
@@ -0,0 +1,31 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.mockito.InjectMocks;
+
+class EnvironmentInterpolatorTest {
+
+    private final String property = "property";
+
+    @InjectMocks
+    private EnvironmentInterpolator interpolator;
+
+    @AfterEach
+    void afterEach() {
+        System.clearProperty(property);
+    }
+
+    @Test
+    @DisplayName("getConsumer should return System::getenv")
+    void getConsumer() throws Exception {
+        final String value = "value";
+
+        withEnvironmentVariable(property, value)
+                .execute(() -> assertEquals(value, interpolator.getConsumer().apply(property)));
+    }
+}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java
new file mode 100644
index 000000000..0a87ade0a
--- /dev/null
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java
@@ -0,0 +1,125 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.inOrder;
+import static org.mockito.Mockito.verifyNoInteractions;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import java.util.List;
+import java.util.Optional;
+import java.util.function.Function;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonStreamContext;
+
+import io.github.giulong.spectrum.utils.Reflections;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.mockito.InOrder;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+
+class ExternalInterpolatorTest {
+
+    private final String value = "value";
+
+    @Mock
+    private JsonParser jsonParser;
+
+    @Mock
+    private List<String> accumulator;
+
+    @Mock
+    private JsonStreamContext context;
+
+    @Mock
+    private JsonStreamContext parentContext;
+
+    @Mock
+    private JsonStreamContext grandParentContext;
+
+    @InjectMocks
+    private DummyExternalInterpolator interpolator;
+
+    @InjectMocks
+    private DummyNotFoundExternalInterpolator interpolatorNotFound;
+
+    @BeforeEach
+    void beforeEach() {
+        Reflections.setField("prefix", interpolator, "prefix");
+        Reflections.setField("delimiter", interpolator, ".");
+
+        Reflections.setField("prefix", interpolatorNotFound, "prefix");
+        Reflections.setField("delimiter", interpolatorNotFound, ".");
+    }
+
+    @Test
+    @DisplayName("findVariableFor should return an empty optional if no variable is found")
+    void findVariableForEmpty() {
+        when(context.getParent()).thenReturn(null);
+        when(jsonParser.getParsingContext()).thenReturn(context);
+
+        assertEquals(Optional.empty(), interpolatorNotFound.findVariableFor(value, jsonParser));
+    }
+
+    @Test
+    @DisplayName("findVariableFor should return an optional containing the variable found")
+    void findVariableFor() {
+        when(context.getParent()).thenReturn(null);
+        when(jsonParser.getParsingContext()).thenReturn(context);
+
+        assertEquals(Optional.of("prefixFound"), interpolator.findVariableFor(value, jsonParser));
+    }
+
+    @Test
+    @DisplayName("getKeyPathTokens should stop when parent context is null")
+    void getKeyPathTokensNoParentContext() {
+        when(context.getParent()).thenReturn(null);
+
+        interpolator.getKeyPathTokens(accumulator, context);
+
+        verifyNoInteractions(accumulator);
+        verifyNoMoreInteractions(context);
+    }
+
+    @Test
+    @DisplayName("getKeyPathTokens should collect all the tokens in the provided accumulator")
+    void getKeyPathTokens() {
+        final String currentName = "currentName";
+        final String parentCurrentName = "parentCurrentName";
+
+        when(context.getParent()).thenReturn(parentContext);
+        when(parentContext.getParent()).thenReturn(grandParentContext);
+        when(grandParentContext.getParent()).thenReturn(null);
+
+        when(context.getCurrentName()).thenReturn(currentName);
+        when(parentContext.getCurrentName()).thenReturn(parentCurrentName);
+
+        final InOrder inOrder = inOrder(accumulator);
+
+        interpolator.getKeyPathTokens(accumulator, context);
+
+        inOrder.verify(accumulator).add(parentCurrentName);
+        inOrder.verify(accumulator).add(currentName);
+        verifyNoMoreInteractions(grandParentContext);
+    }
+
+    private static final class DummyExternalInterpolator extends ExternalInterpolator {
+
+        @Override
+        public Function<String, String> getConsumer() {
+            return s -> s + "Found";
+        }
+    }
+
+    private static final class DummyNotFoundExternalInterpolator extends ExternalInterpolator {
+
+        @Override
+        public Function<String, String> getConsumer() {
+            return s -> null;
+        }
+    }
+}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolatorTest.java
new file mode 100644
index 000000000..15e5f3741
--- /dev/null
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/PropertiesInterpolatorTest.java
@@ -0,0 +1,31 @@
+package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.mockito.InjectMocks;
+
+class PropertiesInterpolatorTest {
+
+    private final String property = "property";
+
+    @InjectMocks
+    private PropertiesInterpolator interpolator;
+
+    @AfterEach
+    void afterEach() {
+        System.clearProperty(property);
+    }
+
+    @Test
+    @DisplayName("getConsumer should return System::getProperty")
+    void getConsumer() {
+        final String value = "value";
+
+        System.setProperty(property, value);
+
+        assertEquals(value, interpolator.getConsumer().apply(property));
+    }
+}
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/utils/ReflectionsTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/utils/ReflectionsTest.java
index 627d74396..5bd97c2eb 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/utils/ReflectionsTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/utils/ReflectionsTest.java
@@ -43,6 +43,17 @@ static Stream<Arguments> valuesProvider() {
                 arguments(Dummy.class, Object.class, List.of("fieldString", "secured", "parentField")));
     }
 
+    @Test
+    @DisplayName("getFieldsValueOf should return all the fields of the provided object of the provided type")
+    void getFieldsValueOf() {
+        final String fieldName = "fieldString";
+        final String secured = "secured";
+        final Dummy dummy = new Dummy(fieldName, secured, null);
+
+        final List<String> values = Reflections.getFieldsValueOf(dummy);
+        assertEquals(List.of(fieldName, secured), values);
+    }
+
     @Test
     @DisplayName("getField should return the field with the provided name on the provided object")
     void getField() throws NoSuchFieldException {
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/utils/YamlUtilsTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/utils/YamlUtilsTest.java
index b5ea033d0..c9f7dba48 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/utils/YamlUtilsTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/utils/YamlUtilsTest.java
@@ -24,6 +24,8 @@
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 
@@ -50,6 +52,9 @@ class YamlUtilsTest {
     @Mock
     private FileProvider fileProvider;
 
+    @Captor
+    private ArgumentCaptor<InputStream> inputStreamArgumentCaptor;
+
     @InjectMocks
     private YamlUtils yamlUtils;
 
@@ -173,6 +178,25 @@ void readDynamicDeserializable() throws IOException {
         assertEquals(testYaml, yamlUtils.readDynamicDeserializable("test.yaml", clazz, jsonNode));
     }
 
+    @Test
+    @DisplayName("updateNode should update the provided object with the content of the node at the provided file")
+    void updateNode() throws IOException {
+        final String file = "test.yaml";
+        final String node = "node";
+
+        Reflections.setField("yamlMapper", yamlUtils, yamlMapper);
+        Reflections.setField("clientFileProvider", yamlUtils, fileProvider);
+
+        when(fileProvider.find(file)).thenReturn(file);
+        when(fileProvider.augment(yamlMapper)).thenReturn(reader);
+        when(reader.withValueToUpdate(testYaml)).thenReturn(reader);
+        when(yamlMapper.readTree(inputStreamArgumentCaptor.capture())).thenReturn(jsonNode);
+        when(jsonNode.at(node)).thenReturn(jsonNode);
+        when(reader.readValue(jsonNode)).thenReturn(testYaml);
+
+        yamlUtils.updateNode(testYaml, node, file, fileProvider);
+    }
+
     @DisplayName("updateWithFile should update the provided instance with the file provided, reading only public fields")
     @ParameterizedTest(name = "with file {0}")
     @ValueSource(strings = {"test.yaml", "test.yml", "configurations/test.yaml"})
@@ -183,7 +207,7 @@ void updateWithFile(final String file) throws IOException {
         when(fileProvider.find(file)).thenReturn(file);
         when(fileProvider.augment(yamlMapper)).thenReturn(reader);
         when(reader.withValueToUpdate(testYaml)).thenReturn(reader);
-        when(reader.readValue(any(InputStream.class))).thenReturn(testYaml);
+        when(reader.readValue(inputStreamArgumentCaptor.capture())).thenReturn(testYaml);
 
         yamlUtils.updateWithClientFile(testYaml, file);
     }
@@ -217,6 +241,44 @@ void updateWithInternalFile() throws IOException {
         yamlUtils.updateWithInternalFile(testYaml, file);
     }
 
+    @Test
+    @DisplayName("updateWithInternalNode should update the provided instance with the node of the internal file provided")
+    void updateWithInternalNode() throws IOException {
+        final String file = "test.yaml";
+        final String node = "node";
+
+        Reflections.setField("yamlMapper", yamlUtils, yamlMapper);
+        Reflections.setField("internalFileProvider", yamlUtils, fileProvider);
+
+        when(fileProvider.find(file)).thenReturn(file);
+        when(fileProvider.augment(yamlMapper)).thenReturn(reader);
+        when(reader.withValueToUpdate(testYaml)).thenReturn(reader);
+        when(yamlMapper.readTree(inputStreamArgumentCaptor.capture())).thenReturn(jsonNode);
+        when(jsonNode.at(node)).thenReturn(jsonNode);
+        when(reader.readValue(jsonNode)).thenReturn(testYaml);
+
+        yamlUtils.updateWithInternalNode(testYaml, node, file);
+    }
+
+    @Test
+    @DisplayName("updateWithClientNode should update the provided instance with the node of the client file provided")
+    void updateWithClientNode() throws IOException {
+        final String file = "test.yaml";
+        final String node = "node";
+
+        Reflections.setField("yamlMapper", yamlUtils, yamlMapper);
+        Reflections.setField("clientFileProvider", yamlUtils, fileProvider);
+
+        when(fileProvider.find(file)).thenReturn(file);
+        when(fileProvider.augment(yamlMapper)).thenReturn(reader);
+        when(reader.withValueToUpdate(testYaml)).thenReturn(reader);
+        when(yamlMapper.readTree(inputStreamArgumentCaptor.capture())).thenReturn(jsonNode);
+        when(jsonNode.at(node)).thenReturn(jsonNode);
+        when(reader.readValue(jsonNode)).thenReturn(testYaml);
+
+        yamlUtils.updateWithClientNode(testYaml, node, file);
+    }
+
     @Test
     @DisplayName("write should just call the writeValueAsString of the provided object, printing internal fields as well")
     void write() throws JsonProcessingException {
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/utils/file_providers/FileProviderTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/utils/file_providers/FileProviderTest.java
index c7797cbae..e2db50214 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/utils/file_providers/FileProviderTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/utils/file_providers/FileProviderTest.java
@@ -33,9 +33,9 @@ class FileProviderTest {
     @Test
     @DisplayName("augment should return the reader augmented with views and injectable values from the provided mapper")
     void augment() {
+        when(mapper.setInjectableValues(std)).thenReturn(mapper);
         when(mapper.reader()).thenReturn(reader);
         when(reader.withView(Views.Client.class)).thenReturn(reader);
-        when(reader.with(std)).thenReturn(reader);
 
         assertEquals(reader, fileProvider.augment(mapper));
     }

From b2d41562950477a158ade8fce34aeed93769929f Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Wed, 3 Dec 2025 22:23:57 +0100
Subject: [PATCH 03/20] fix(external interpolation): ConfigurationInterpolator
 returns an empty optional if no interpolation happened

---
 .../ConfigurationInterpolator.java              |  4 ++--
 .../ConfigurationInterpolatorTest.java          | 17 ++++++++++++-----
 2 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
index 6dbe64a43..87e580027 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
@@ -46,11 +46,11 @@ public Optional<String> findVariableFor(final String value, final JsonParser jso
                 log.trace("Interpolated value for key '{}: {}' -> '{}'", currentName, value, interpolatedValue);
 
                 if (PATTERN.matcher(interpolatedValue).find()) {
-                    interpolatedValue = findVariableFor(interpolatedValue, jsonParser).orElseThrow();
+                    interpolatedValue = findVariableFor(interpolatedValue, jsonParser).orElse(value);
                 }
             }
         }
 
-        return Optional.of(interpolatedValue);
+        return interpolatedValue.equals(value) ? Optional.empty() : Optional.of(interpolatedValue);
     }
 }
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
index 33b3ed38c..39cab1501 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
@@ -20,6 +20,7 @@
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.params.provider.ValueSource;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 
@@ -45,7 +46,7 @@ public static void afterAll() {
         Vars.getInstance().clear();
     }
 
-    @DisplayName("findVariableFor should find the right value")
+    @DisplayName("findVariableFor should find the right value and return an optional containing it")
     @ParameterizedTest(name = "with value {0} we expect {1}")
     @MethodSource("valuesProvider")
     void deserialize(final String value, final String expected) throws IOException {
@@ -56,7 +57,6 @@ void deserialize(final String value, final String expected) throws IOException {
 
     static Stream<Arguments> valuesProvider() {
         return Stream.of(
-                arguments("value", "value"),
                 arguments("${not.set:-_-}", "_-"),
                 arguments("${not.set:-- -}", "- -"),
                 arguments("${not.set:--\t-}", "-\t-"),
@@ -71,9 +71,16 @@ static Stream<Arguments> valuesProvider() {
                 arguments("${notSet:-}", ""),
                 arguments("${varInEnv:-local}", VAR_IN_ENV),
                 arguments("${varInEnv}", VAR_IN_ENV),
-                arguments("${varInEnv:-~/local}", VAR_IN_ENV),
-                arguments("${not.set}", "${not.set}"),
-                arguments("${notSet}", "${notSet}"));
+                arguments("${varInEnv:-~/local}", VAR_IN_ENV));
+    }
+
+    @DisplayName("findVariableFor should return an empty optional if no value to interpolate is found")
+    @ParameterizedTest(name = "with value {0}")
+    @ValueSource(strings = {"value", "${not.set}", "${notSet}"})
+    void deserializeNotMatching(final String value) throws IOException {
+        when(jsonParser.currentName()).thenReturn(currentName);
+
+        assertEquals(Optional.empty(), interpolator.findVariableFor(value, jsonParser));
     }
 
     @Test

From 0fde701916f08abfc96f1e49bc2e0158cc748e4f Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Wed, 3 Dec 2025 22:37:23 +0100
Subject: [PATCH 04/20] test: re-enabling and cleaning
 InterpolatedStringDeserializerTest

---
 .../InterpolatedStringDeserializerTest.java   | 99 +++----------------
 1 file changed, 11 insertions(+), 88 deletions(-)

diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java
index c459f8927..8d78d9c97 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializerTest.java
@@ -1,17 +1,15 @@
 package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
-import static com.github.stefanbirkner.systemlambda.SystemLambda.withEnvironmentVariable;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.matchesPattern;
-import static org.junit.jupiter.api.Assertions.*;
-import static org.junit.jupiter.params.provider.Arguments.arguments;
+import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.mockito.Mockito.mockStatic;
+import static org.mockito.Mockito.verifyNoInteractions;
 import static org.mockito.Mockito.when;
 
 import java.io.IOException;
 import java.util.List;
 import java.util.Optional;
-import java.util.stream.Stream;
 
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.databind.DeserializationContext;
@@ -21,21 +19,17 @@
 import io.github.giulong.spectrum.utils.Configuration.Config;
 import io.github.giulong.spectrum.utils.Configuration.Config.Interpolators;
 import io.github.giulong.spectrum.utils.Reflections;
-import io.github.giulong.spectrum.utils.Vars;
 
-import org.junit.jupiter.api.*;
-import org.junit.jupiter.params.ParameterizedTest;
-import org.junit.jupiter.params.provider.Arguments;
-import org.junit.jupiter.params.provider.MethodSource;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.MockedStatic;
 
-@Disabled
 class InterpolatedStringDeserializerTest {
 
-    private static final String VAR_IN_ENV = "varInEnv";
-
     private MockedStatic<Reflections> reflectionsMockedStatic;
 
     @Mock
@@ -59,11 +53,6 @@ class InterpolatedStringDeserializerTest {
     @InjectMocks
     private InterpolatedStringDeserializer deserializer;
 
-    @BeforeAll
-    public static void beforeAll() {
-        Vars.getInstance().put("varInEnv", VAR_IN_ENV);
-    }
-
     @BeforeEach
     void beforeEach() {
         Reflections.setField("configuration", deserializer, configuration);
@@ -76,11 +65,6 @@ void afterEach() {
         reflectionsMockedStatic.close();
     }
 
-    @AfterAll
-    public static void afterAll() {
-        Vars.getInstance().clear();
-    }
-
     @Test
     @DisplayName("getInstance should return the singleton")
     void getInstance() {
@@ -88,82 +72,21 @@ void getInstance() {
         assertSame(InterpolatedStringDeserializer.getInstance(), InterpolatedStringDeserializer.getInstance());
     }
 
-    @DisplayName("deserialize should delegate to the parent method passing the string value")
-    @ParameterizedTest(name = "with value {0} we expect {1}")
-    @MethodSource("valuesProvider")
-    void deserialize(final String value, final String expected) throws IOException {
-        interpolateStubsFor(value);
-
-        when(jsonParser.getValueAsString()).thenReturn(value);
-
-        assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext));
-    }
-
-    static Stream<Arguments> valuesProvider() {
-        return Stream.of(
-                arguments("value", "value"),
-                arguments("${not.set:-_-}", "_-"),
-                arguments("${not.set:-- -}", "- -"),
-                arguments("${not.set:--\t-}", "-\t-"),
-                arguments("${not.set:-a b }", "a b "),
-                arguments("${not.set:-local}", "local"),
-                arguments("${notSet:-local}", "local"),
-                arguments("${notSet:-local}-something_else-${varInEnv}", "local-something_else-" + VAR_IN_ENV),
-                arguments("${notSet:-${varInEnv:-local}}-nested", VAR_IN_ENV + "-nested"),
-                arguments("${notSet:-${varInEnv:-local}}-nested-${varInEnv}", VAR_IN_ENV + "-nested-" + VAR_IN_ENV),
-                arguments("${notSet:-local.dots}", "local.dots"),
-                arguments("${notSet:---key=value}", "--key=value"),
-                arguments("${notSet:-}", ""),
-                arguments("${varInEnv:-local}", VAR_IN_ENV),
-                arguments("${varInEnv}", VAR_IN_ENV),
-                arguments("${varInEnv:-~/local}", VAR_IN_ENV),
-                arguments("${not.set}", "${not.set}"),
-                arguments("${notSet}", "${notSet}"));
-    }
-
     @Test
-    @DisplayName("deserialize should interpolate the timestamp")
+    @DisplayName("deserialize should delegate to the parent method passing the string value, interpolating the timestamp")
     void deserializeTimestamp() throws IOException {
         final String value = "value-${timestamp}";
 
-        interpolateStubsFor(value);
         when(jsonParser.getValueAsString()).thenReturn(value);
 
-        assertThat(deserializer.deserialize(jsonParser, deserializationContext), matchesPattern("value-[0-9]{2}-[0-9]{2}-[0-9]{4}_[0-9]{2}-[0-9]{2}-[0-9]{2}"));
-    }
-
-    @Test
-    @DisplayName("deserialize should consider system properties")
-    void deserializeFromSystemProperty() throws Exception {
-        final String expected = "expected";
-        System.setProperty("systemProperty", expected);
-
-        when(jsonParser.getValueAsString()).thenReturn("${systemProperty:-local}");
-
-        // We set the "systemProperty" env var with a random value just to check the precedence: system property wins
-        withEnvironmentVariable("systemProperty", "SOME VALUE")
-                .execute(() -> assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext)));
-
-        System.clearProperty("systemProperty");
-    }
-
-    @Test
-    @DisplayName("deserialize should consider env variables")
-    void deserializeFromEnvVariables() throws Exception {
-        final String expected = "expected";
-
-        interpolateStubsFor(expected);
-        when(jsonParser.getValueAsString()).thenReturn("${envVar:-local}");
-
-        withEnvironmentVariable("envVar", expected).execute(() -> assertEquals(expected, deserializer.deserialize(jsonParser, deserializationContext)));
-    }
-
-    private void interpolateStubsFor(final String value) {
+        // parent interpolate
         when(configuration.getConfig()).thenReturn(config);
         when(config.getInterpolators()).thenReturn(interpolators);
         when(Reflections.getFieldsValueOf(interpolators)).thenReturn(List.of(interpolator));
         when(interpolator.isEnabled()).thenReturn(true);
-
         when(interpolator.findVariableFor(value, jsonParser)).thenReturn(Optional.of(value));
+
+        assertThat(deserializer.deserialize(jsonParser, deserializationContext), matchesPattern("value-[0-9]{2}-[0-9]{2}-[0-9]{4}_[0-9]{2}-[0-9]{2}-[0-9]{2}"));
+        verifyNoInteractions(deserializationContext);
     }
 }

From bc606bf0588d925bbf097da955f62459e1997f94 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Fri, 5 Dec 2025 22:48:07 +0100
Subject: [PATCH 05/20] refactor: aligning profile id in it-windows module to
 others

---
 it-windows/pom.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/it-windows/pom.xml b/it-windows/pom.xml
index f15f50dfe..b55804fa4 100644
--- a/it-windows/pom.xml
+++ b/it-windows/pom.xml
@@ -59,7 +59,7 @@
 
     <profiles>
         <profile>
-            <id>windows</id>
+            <id>chrome</id>
             <activation>
                 <property>
                     <name>windowsTests</name>

From 490464f00aba81a656c794d274c01cbe1ad65265 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Fri, 5 Dec 2025 23:04:11 +0100
Subject: [PATCH 06/20] fix(external interpolation): config node is read from
 the base configuration.yaml only, not from profile configurations

---
 .../spectrum/SpectrumSessionListener.java     | 26 +++++++++----------
 .../giulong/spectrum/utils/Configuration.java |  2 +-
 .../resources/yaml/configuration.default.yaml |  2 +-
 .../spectrum/SpectrumSessionListenerTest.java | 19 ++------------
 4 files changed, 16 insertions(+), 33 deletions(-)

diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java b/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java
index 6b2a7934b..cbe69ef4f 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/SpectrumSessionListener.java
@@ -43,6 +43,7 @@ public void launcherSessionOpened(final LauncherSession session) {
         final ProjectProperties projectProperties = yamlUtils.readInternal("properties.yaml", ProjectProperties.class);
         log.info(freeMarkerWrapper.interpolate(fileUtils.read("banner.txt"), projectProperties));
 
+        parseConfig();
         parseConfiguration();
         session.getLauncher().registerTestExecutionListeners(configuration.getSummary().getSummaryGeneratingListener());
 
@@ -66,13 +67,23 @@ public void launcherSessionClosed(final LauncherSession session) {
         eventsDispatcher.sessionClosed();
     }
 
+    void parseConfig() {
+        final Config config = yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML);
+
+        if (isUnix()) {
+            yamlUtils.updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
+        }
+
+        yamlUtils.updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
+        configuration.setConfig(config);
+    }
+
     void parseConfiguration() {
         final List<String> profileConfigurations = parseProfiles()
                 .stream()
                 .map(profile -> String.format("configuration-%s", profile))
                 .toList();
 
-        parseConfig(profileConfigurations);
         parseVars(profileConfigurations);
 
         yamlUtils.updateWithInternalFile(configuration, DEFAULT_CONFIGURATION_YAML);
@@ -96,19 +107,6 @@ List<String> parseProfiles() {
                 .toList();
     }
 
-    void parseConfig(final List<String> profileConfigurations) {
-        final Config config = yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML);
-
-        if (isUnix()) {
-            yamlUtils.updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
-        }
-
-        yamlUtils.updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
-        profileConfigurations.forEach(p -> yamlUtils.updateWithClientNode(config, CONFIG_NODE, p));
-
-        configuration.setConfig(config);
-    }
-
     void parseVars(final List<String> profileConfigurations) {
         vars.putAll(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML));
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
index 5e82df166..247737892 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
@@ -42,7 +42,7 @@ public class Configuration {
 
     @Setter
     @JsonIgnore
-    @JsonPropertyDescription("Generic configuration")
+    @JsonPropertyDescription("Generic configuration. This node is read only from the base configuration.yaml")
     private Config config;
 
     @JsonPropertyDescription("Common vars to interpolate other String values in the configuration")
diff --git a/spectrum/src/main/resources/yaml/configuration.default.yaml b/spectrum/src/main/resources/yaml/configuration.default.yaml
index c19f88147..cde2bcc80 100644
--- a/spectrum/src/main/resources/yaml/configuration.default.yaml
+++ b/spectrum/src/main/resources/yaml/configuration.default.yaml
@@ -1,4 +1,4 @@
-# Generic configuration
+# Generic configuration. This node is read only from the base configuration.yaml
 config:
   interpolators: # Configuration keys interpolators
     environment: # Environment variables interpolator
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java
index a8c97c331..14d7e85b2 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/SpectrumSessionListenerTest.java
@@ -190,9 +190,6 @@ void parseConfigurationNoProfile() {
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn("");
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
 
-        // parseConfig
-        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
-
         // parseVars
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
 
@@ -214,9 +211,6 @@ void parseConfiguration() {
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn(profile);
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
 
-        // parseConfig
-        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
-
         // parseVars
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
 
@@ -239,9 +233,6 @@ void parseConfigurationUnix() {
         when(yamlUtils.readClientNode(PROFILE_NODE, CONFIGURATION)).thenReturn(profile);
         when(yamlUtils.readInternalNode(PROFILE_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn("defaultProfile");
 
-        // parseConfig
-        when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
-
         // parseVars
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(Map.of("one", "one"));
         when(yamlUtils.readInternalNode(VARS_NODE, DEFAULT_CONFIGURATION_UNIX_YAML)).thenReturn(Map.of("one", "one"));
@@ -277,33 +268,27 @@ static Stream<Arguments> profilesValuesProvider() {
     @Test
     @DisplayName("parseConfig should parse the config node read from the configuration yaml files")
     void parseConfig() {
-        final String profileConfiguration = "profileConfiguration";
-
         System.setProperty("os.name", "Win");
 
         when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
 
-        spectrumSessionListener.parseConfig(List.of(profileConfiguration));
+        spectrumSessionListener.parseConfig();
 
         verify(yamlUtils, never()).updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
         verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
-        verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, profileConfiguration);
     }
 
     @Test
     @DisplayName("parseConfig should parse the also the config node read from the internal configuration.default.unix.yaml")
     void parseConfigUnix() {
-        final String profileConfiguration = "profileConfiguration";
-
         System.setProperty("os.name", "nix");
 
         when(yamlUtils.readInternalNode(CONFIG_NODE, DEFAULT_CONFIGURATION_YAML)).thenReturn(config);
 
-        spectrumSessionListener.parseConfig(List.of(profileConfiguration));
+        spectrumSessionListener.parseConfig();
 
         verify(yamlUtils).updateWithInternalNode(config, CONFIG_NODE, DEFAULT_CONFIGURATION_UNIX_YAML);
         verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, CONFIGURATION);
-        verify(yamlUtils).updateWithClientNode(config, CONFIG_NODE, profileConfiguration);
     }
 
     @DisplayName("parseVars should put in the VARS map all the variables read from the configuration yaml files")

From b89cb69bc03333a1ac2091594f26fc3fac512664 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Sat, 6 Dec 2025 11:09:18 +0100
Subject: [PATCH 07/20] test(external interpolation): moving a couple
 configuration keys in system properties and env variables to test external
 interpolation

---
 it/pom.xml                               | 9 +++++++++
 it/src/test/resources/configuration.yaml | 5 ++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/it/pom.xml b/it/pom.xml
index 1ca76bd7c..82a00c0df 100644
--- a/it/pom.xml
+++ b/it/pom.xml
@@ -53,6 +53,15 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-failsafe-plugin</artifactId>
+                <configuration>
+                    <environmentVariables>
+                        <spectrum.video.skipDuplicateFrames>false</spectrum.video.skipDuplicateFrames>
+                        <spectrum.application.baseUrl>overridden by the property below</spectrum.application.baseUrl>
+                    </environmentVariables>
+                    <systemPropertyVariables>
+                        <spectrum.application.baseUrl>https://the-internet.herokuapp.com/</spectrum.application.baseUrl>
+                    </systemPropertyVariables>
+                </configuration>
             </plugin>
         </plugins>
     </build>
diff --git a/it/src/test/resources/configuration.yaml b/it/src/test/resources/configuration.yaml
index aca3003ba..bfcbf4d98 100644
--- a/it/src/test/resources/configuration.yaml
+++ b/it/src/test/resources/configuration.yaml
@@ -3,8 +3,7 @@ config:
     environment: { }
     properties: { }
 
-application:
-  baseUrl: https://the-internet.herokuapp.com/
+# application.baseUrl set as system property in pom.xml
 
 drivers:
   waits:
@@ -23,7 +22,7 @@ video:
   frames:
     - autoAfter
     - manual
-  skipDuplicateFrames: false
+  # skipDuplicateFrames: false set as env variable in pom.xml
 
 extent:
   theme: DARK

From cf5c80525d2a91afd099d114c9df6d939f03a4f0 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Sat, 6 Dec 2025 23:50:40 +0100
Subject: [PATCH 08/20] build(external interpolation): setting
 spectrum.video.skipDuplicateFrames to false as env var in gh build action

---
 .github/workflows/build.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ace89a032..1a9c7d36c 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -74,6 +74,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     env:
       VERSION: ${{ needs.build.outputs.version }}
+      spectrum.video.skipDuplicateFrames: false
     steps:
       - name: Free Disk Space
         if: ${{ matrix.os != 'windows-latest' }}

From b92af6734f8673ae884f397bfec22bf9f694a233 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Sun, 7 Dec 2025 15:35:57 +0100
Subject: [PATCH 09/20] refactor: cleaning interpolated deserializers

---
 .../interpolation/DriverDeserializer.java           |  6 +-----
 .../interpolation/EnvironmentDeserializer.java      |  6 +-----
 .../InterpolatedBooleanDeserializer.java            |  7 +------
 .../interpolation/InterpolatedDeserializer.java     | 13 ++++++++++++-
 .../InterpolatedStringDeserializer.java             |  8 +-------
 5 files changed, 16 insertions(+), 24 deletions(-)

diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java
index 71f1504b8..0d6f68e08 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/DriverDeserializer.java
@@ -10,9 +10,7 @@
 import io.github.giulong.spectrum.drivers.*;
 
 import lombok.NoArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
 
-@Slf4j
 @NoArgsConstructor(access = PRIVATE)
 public class DriverDeserializer extends InterpolatedDeserializer<Driver<?, ?, ?>> {
 
@@ -24,9 +22,7 @@ public static DriverDeserializer getInstance() {
 
     @Override
     public Driver<?, ?, ?> deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException {
-        final String value = jsonParser.getValueAsString();
-        final String interpolatedValue = interpolate(value, jsonParser);
-        log.trace("Deserializing driver from value {} -> {}", value, interpolatedValue);
+        final String interpolatedValue = interpolate(jsonParser);
 
         return switch (interpolatedValue) {
             case "chrome" -> new Chrome();
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java
index 21e80c89d..812a3088f 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/EnvironmentDeserializer.java
@@ -13,9 +13,7 @@
 import io.github.giulong.spectrum.utils.environments.LocalEnvironment;
 
 import lombok.NoArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
 
-@Slf4j
 @NoArgsConstructor(access = PRIVATE)
 public class EnvironmentDeserializer extends InterpolatedDeserializer<Environment> {
 
@@ -27,9 +25,7 @@ public static EnvironmentDeserializer getInstance() {
 
     @Override
     public Environment deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException {
-        final String value = jsonParser.getValueAsString();
-        final String interpolatedValue = interpolate(value, jsonParser);
-        log.trace("Deserializing environment from value {} -> {}", value, interpolatedValue);
+        final String interpolatedValue = interpolate(jsonParser);
 
         return switch (interpolatedValue) {
             case "local" -> new LocalEnvironment();
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java
index e1e238a5b..24a8a7960 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedBooleanDeserializer.java
@@ -8,9 +8,7 @@
 import com.fasterxml.jackson.databind.DeserializationContext;
 
 import lombok.NoArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
 
-@Slf4j
 @NoArgsConstructor(access = PRIVATE)
 public class InterpolatedBooleanDeserializer extends InterpolatedDeserializer<Boolean> {
 
@@ -22,9 +20,6 @@ public static InterpolatedBooleanDeserializer getInstance() {
 
     @Override
     public Boolean deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException {
-        final String value = jsonParser.getValueAsString();
-        log.trace("Deserializing Boolean from value {}", value);
-
-        return Boolean.parseBoolean(interpolate(value, jsonParser));
+        return Boolean.parseBoolean(interpolate(jsonParser));
     }
 }
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
index 823e1040b..711f38473 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
@@ -11,6 +11,7 @@
 import io.github.giulong.spectrum.utils.Configuration.Config;
 import io.github.giulong.spectrum.utils.Reflections;
 
+import lombok.SneakyThrows;
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
@@ -18,8 +19,10 @@ public abstract class InterpolatedDeserializer<T> extends JsonDeserializer<T> {
 
     private final Configuration configuration = Configuration.getInstance();
 
+    @SneakyThrows
     public String interpolate(final String value, final JsonParser jsonParser) {
         final Config config = configuration.getConfig();
+        log.trace("{} is deserializing {}: {}", getClass().getSimpleName(), jsonParser.currentName(), value);
 
         if (config != null) {
             final List<Interpolator> interpolators = Reflections.getFieldsValueOf(config.getInterpolators());
@@ -32,10 +35,18 @@ public String interpolate(final String value, final JsonParser jsonParser) {
                     .toList();
 
             if (!values.isEmpty()) {
-                return values.getLast();
+                final String interpolatedValue = values.getLast();
+                log.debug("Chosen interpolated value: {} -> {}", jsonParser.currentName(), interpolatedValue);
+                return interpolatedValue;
             }
         }
 
+        log.trace("No value interpolated. Returning original value: {}", value);
         return value;
     }
+
+    @SneakyThrows
+    public String interpolate(final JsonParser jsonParser) {
+        return interpolate(jsonParser.getValueAsString(), jsonParser);
+    }
 }
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java
index d43a16be4..780013ba8 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedStringDeserializer.java
@@ -10,9 +10,7 @@
 import io.github.giulong.spectrum.utils.FileUtils;
 
 import lombok.NoArgsConstructor;
-import lombok.extern.slf4j.Slf4j;
 
-@Slf4j
 @NoArgsConstructor(access = PRIVATE)
 public class InterpolatedStringDeserializer extends InterpolatedDeserializer<String> {
 
@@ -26,10 +24,6 @@ public static InterpolatedStringDeserializer getInstance() {
 
     @Override
     public String deserialize(final JsonParser jsonParser, final DeserializationContext deserializationContext) throws IOException {
-        final String value = jsonParser.getValueAsString();
-        log.trace("Deserializing String from value {}", value);
-
-        final String interpolatedValue = interpolate(value, jsonParser);
-        return fileUtils.interpolateTimestampFrom(interpolatedValue);
+        return fileUtils.interpolateTimestampFrom(interpolate(jsonParser));
     }
 }

From 60df731f3ef36fa3ff213624f6aee7649ef680d5 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Sun, 7 Dec 2025 18:49:48 +0100
Subject: [PATCH 10/20] fix(external interpolation): exporting env variables in
 bash process in build github action

---
 .github/workflows/build.yml              | 3 ++-
 it/pom.xml                               | 4 ++--
 it/src/test/resources/configuration.yaml | 3 ++-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 1a9c7d36c..30d921d2a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -74,7 +74,6 @@ jobs:
     runs-on: ${{ matrix.os }}
     env:
       VERSION: ${{ needs.build.outputs.version }}
-      spectrum.video.skipDuplicateFrames: false
     steps:
       - name: Free Disk Space
         if: ${{ matrix.os != 'windows-latest' }}
@@ -103,6 +102,8 @@ jobs:
       - name: Run browsers ITs
         shell: bash
         run: |
+          export spectrum_video_skipDuplicateFrames=false
+          export spectrum_application_baseUrl='overridden by system property in pom.xml'
           ./mvnw install:install-file -ntp -Dfile=$GITHUB_WORKSPACE/spectrum-${{ env.VERSION }}.jar -DgroupId=io.github.giulong -DartifactId=spectrum -Dversion=${{ env.VERSION }} -Dpackaging=jar
           ./mvnw install -DskipSign -Dmaven.plugin.validation=NONE ${{ matrix.directives }} -ntp -P ${{ matrix.profiles }}
 
diff --git a/it/pom.xml b/it/pom.xml
index 82a00c0df..7c380eff2 100644
--- a/it/pom.xml
+++ b/it/pom.xml
@@ -55,8 +55,8 @@
                 <artifactId>maven-failsafe-plugin</artifactId>
                 <configuration>
                     <environmentVariables>
-                        <spectrum.video.skipDuplicateFrames>false</spectrum.video.skipDuplicateFrames>
-                        <spectrum.application.baseUrl>overridden by the property below</spectrum.application.baseUrl>
+                        <spectrum_video_skipDuplicateFrames>false</spectrum_video_skipDuplicateFrames>
+                        <spectrum_application_baseUrl>overridden by the property below</spectrum_application_baseUrl>
                     </environmentVariables>
                     <systemPropertyVariables>
                         <spectrum.application.baseUrl>https://the-internet.herokuapp.com/</spectrum.application.baseUrl>
diff --git a/it/src/test/resources/configuration.yaml b/it/src/test/resources/configuration.yaml
index bfcbf4d98..f7f0aa9f9 100644
--- a/it/src/test/resources/configuration.yaml
+++ b/it/src/test/resources/configuration.yaml
@@ -1,6 +1,7 @@
 config:
   interpolators:
-    environment: { }
+    environment:
+      delimiter: _
     properties: { }
 
 # application.baseUrl set as system property in pom.xml

From 86d9d47f783cb5028cf9529ea5f54f154eb9d5b7 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Sun, 7 Dec 2025 19:09:25 +0100
Subject: [PATCH 11/20] feat(external interpolation): introducing interpolators
 priority to override the declaration order

---
 .github/workflows/build.yml                                | 2 +-
 it/pom.xml                                                 | 4 ++--
 it/src/test/resources/configuration.yaml                   | 1 +
 .../interpolation/InterpolatedDeserializer.java            | 5 ++++-
 .../interpolation/interpolators/Interpolator.java          | 4 ++++
 .../src/main/resources/yaml/configuration.default.yaml     | 3 +++
 .../interpolation/InterpolatedDeserializerTest.java        | 7 +++++--
 7 files changed, 20 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 30d921d2a..0b77f2593 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -103,7 +103,7 @@ jobs:
         shell: bash
         run: |
           export spectrum_video_skipDuplicateFrames=false
-          export spectrum_application_baseUrl='overridden by system property in pom.xml'
+          export spectrum_application_baseUrl='https://the-internet.herokuapp.com/'
           ./mvnw install:install-file -ntp -Dfile=$GITHUB_WORKSPACE/spectrum-${{ env.VERSION }}.jar -DgroupId=io.github.giulong -DartifactId=spectrum -Dversion=${{ env.VERSION }} -Dpackaging=jar
           ./mvnw install -DskipSign -Dmaven.plugin.validation=NONE ${{ matrix.directives }} -ntp -P ${{ matrix.profiles }}
 
diff --git a/it/pom.xml b/it/pom.xml
index 7c380eff2..53a651900 100644
--- a/it/pom.xml
+++ b/it/pom.xml
@@ -56,10 +56,10 @@
                 <configuration>
                     <environmentVariables>
                         <spectrum_video_skipDuplicateFrames>false</spectrum_video_skipDuplicateFrames>
-                        <spectrum_application_baseUrl>overridden by the property below</spectrum_application_baseUrl>
+                        <spectrum_application_baseUrl>https://the-internet.herokuapp.com/</spectrum_application_baseUrl>
                     </environmentVariables>
                     <systemPropertyVariables>
-                        <spectrum.application.baseUrl>https://the-internet.herokuapp.com/</spectrum.application.baseUrl>
+                        <spectrum.application.baseUrl>overridden by the env variable above</spectrum.application.baseUrl>
                     </systemPropertyVariables>
                 </configuration>
             </plugin>
diff --git a/it/src/test/resources/configuration.yaml b/it/src/test/resources/configuration.yaml
index f7f0aa9f9..36822f3e5 100644
--- a/it/src/test/resources/configuration.yaml
+++ b/it/src/test/resources/configuration.yaml
@@ -1,6 +1,7 @@
 config:
   interpolators:
     environment:
+      priority: 10
       delimiter: _
     properties: { }
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
index 711f38473..ef41c44ac 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
@@ -1,5 +1,7 @@
 package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation;
 
+import static java.util.Comparator.comparing;
+
 import java.util.List;
 import java.util.Optional;
 
@@ -29,6 +31,7 @@ public String interpolate(final String value, final JsonParser jsonParser) {
             final List<String> values = interpolators
                     .stream()
                     .filter(Interpolator::isEnabled)
+                    .sorted(comparing(Interpolator::getPriority))
                     .map(i -> i.findVariableFor(value, jsonParser))
                     .filter(Optional::isPresent)
                     .map(Optional::get)
@@ -41,7 +44,7 @@ public String interpolate(final String value, final JsonParser jsonParser) {
             }
         }
 
-        log.trace("No value interpolated. Returning original value: {}", value);
+        log.debug("No value interpolated. Returning original value: {}", value);
         return value;
     }
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java
index 45a8cc479..5a20ed2fc 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/Interpolator.java
@@ -16,5 +16,9 @@ public abstract class Interpolator {
     @JsonPropertyDescription("Whether to enable this interpolator. Injected to true by default, so no need to explicitly set it")
     private boolean enabled;
 
+    @SuppressWarnings("unused")
+    @JsonPropertyDescription("Sets the order of evaluation of this interpolator among others. Higher priority wins.")
+    private int priority;
+
     public abstract Optional<String> findVariableFor(String value, JsonParser jsonParser);
 }
diff --git a/spectrum/src/main/resources/yaml/configuration.default.yaml b/spectrum/src/main/resources/yaml/configuration.default.yaml
index cde2bcc80..2909ecd79 100644
--- a/spectrum/src/main/resources/yaml/configuration.default.yaml
+++ b/spectrum/src/main/resources/yaml/configuration.default.yaml
@@ -2,12 +2,15 @@
 config:
   interpolators: # Configuration keys interpolators
     environment: # Environment variables interpolator
+      priority: 0 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
     properties: # Properties interpolator
+      priority: 1 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
     configuration: # In-place configuration file interpolator
+      priority: 2 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       enabled: true
 
 # Common vars to interpolate other String values in the configuration
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
index 701de10ac..ce7e8858e 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
@@ -79,7 +79,7 @@ void interpolateNoConfig() {
     }
 
     @Test
-    @DisplayName("interpolate should return the last interpolated value of the interpolators which found the key")
+    @DisplayName("interpolate should return the last interpolated value of the interpolators which found the key, respecting their priorities")
     void interpolate() {
         final String interpolatedValue1 = "interpolatedValue1";
         final String interpolatedValue2 = "interpolatedValue2";
@@ -92,11 +92,14 @@ void interpolate() {
         when(interpolator3.isEnabled()).thenReturn(true);
         when(interpolator4.isEnabled()).thenReturn(true);
 
+        when(interpolator3.getPriority()).thenReturn(2);
+        when(interpolator4.getPriority()).thenReturn(1);
+
         when(interpolator2.findVariableFor(value, jsonParser)).thenReturn(Optional.empty());
         when(interpolator3.findVariableFor(value, jsonParser)).thenReturn(Optional.of(interpolatedValue1));
         when(interpolator4.findVariableFor(value, jsonParser)).thenReturn(Optional.of(interpolatedValue2));
 
-        assertEquals(interpolatedValue2, deserializer.interpolate(value, jsonParser));
+        assertEquals(interpolatedValue1, deserializer.interpolate(value, jsonParser));
 
         verifyNoMoreInteractions(interpolator1);
     }

From e44ba951fce603d3cf9dabaa8ffa204811ce972b Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Sun, 7 Dec 2025 22:03:08 +0100
Subject: [PATCH 12/20] refactor(external interpolation): short circuiting on
 first interpolated value found leveraging interpolators priority

---
 it/src/test/resources/configuration.yaml       |  3 ++-
 .../InterpolatedDeserializer.java              | 18 ++++++++----------
 .../InterpolatedDeserializerTest.java          |  6 +++---
 3 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/it/src/test/resources/configuration.yaml b/it/src/test/resources/configuration.yaml
index 36822f3e5..e5cf1473f 100644
--- a/it/src/test/resources/configuration.yaml
+++ b/it/src/test/resources/configuration.yaml
@@ -5,7 +5,8 @@ config:
       delimiter: _
     properties: { }
 
-# application.baseUrl set as system property in pom.xml
+application:
+  baseUrl: set as env var in pom.xml. Environment interpolator has a higher priority (see above)
 
 drivers:
   waits:
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
index ef41c44ac..126050cdc 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
@@ -24,27 +24,25 @@ public abstract class InterpolatedDeserializer<T> extends JsonDeserializer<T> {
     @SneakyThrows
     public String interpolate(final String value, final JsonParser jsonParser) {
         final Config config = configuration.getConfig();
-        log.trace("{} is deserializing {}: {}", getClass().getSimpleName(), jsonParser.currentName(), value);
+        final String currentName = jsonParser.currentName();
+        log.trace("{} is deserializing {}: {}", getClass().getSimpleName(), currentName, value);
 
         if (config != null) {
             final List<Interpolator> interpolators = Reflections.getFieldsValueOf(config.getInterpolators());
-            final List<String> values = interpolators
+            final String interpolatedValue = interpolators
                     .stream()
                     .filter(Interpolator::isEnabled)
-                    .sorted(comparing(Interpolator::getPriority))
+                    .sorted(comparing(Interpolator::getPriority).reversed())
                     .map(i -> i.findVariableFor(value, jsonParser))
                     .filter(Optional::isPresent)
                     .map(Optional::get)
-                    .toList();
+                    .findFirst()
+                    .orElse(value);
 
-            if (!values.isEmpty()) {
-                final String interpolatedValue = values.getLast();
-                log.debug("Chosen interpolated value: {} -> {}", jsonParser.currentName(), interpolatedValue);
-                return interpolatedValue;
-            }
+            log.error("Chosen value: {} -> {}", currentName, interpolatedValue);
+            return interpolatedValue;
         }
 
-        log.debug("No value interpolated. Returning original value: {}", value);
         return value;
     }
 
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
index ce7e8858e..6e20882cc 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializerTest.java
@@ -82,7 +82,6 @@ void interpolateNoConfig() {
     @DisplayName("interpolate should return the last interpolated value of the interpolators which found the key, respecting their priorities")
     void interpolate() {
         final String interpolatedValue1 = "interpolatedValue1";
-        final String interpolatedValue2 = "interpolatedValue2";
 
         when(configuration.getConfig()).thenReturn(config);
         when(config.getInterpolators()).thenReturn(interpolators);
@@ -92,16 +91,17 @@ void interpolate() {
         when(interpolator3.isEnabled()).thenReturn(true);
         when(interpolator4.isEnabled()).thenReturn(true);
 
+        when(interpolator2.getPriority()).thenReturn(0);
         when(interpolator3.getPriority()).thenReturn(2);
         when(interpolator4.getPriority()).thenReturn(1);
 
-        when(interpolator2.findVariableFor(value, jsonParser)).thenReturn(Optional.empty());
         when(interpolator3.findVariableFor(value, jsonParser)).thenReturn(Optional.of(interpolatedValue1));
-        when(interpolator4.findVariableFor(value, jsonParser)).thenReturn(Optional.of(interpolatedValue2));
 
         assertEquals(interpolatedValue1, deserializer.interpolate(value, jsonParser));
 
         verifyNoMoreInteractions(interpolator1);
+        verifyNoMoreInteractions(interpolator2);
+        verifyNoMoreInteractions(interpolator4);
     }
 
     @Test

From 16f6967c3dd477b30003407ef3a170fd855977e2 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Mon, 8 Dec 2025 15:09:26 +0000
Subject: [PATCH 13/20] build(deps): bump selenium.version from 4.38.0 to
 4.39.0

Bumps `selenium.version` from 4.38.0 to 4.39.0.

Updates `org.seleniumhq.selenium:selenium-java` from 4.38.0 to 4.39.0
- [Release notes](https://github.com/SeleniumHQ/selenium/releases)
- [Commits](https://github.com/SeleniumHQ/selenium/compare/selenium-4.38.0...selenium-4.39.0)

Updates `org.seleniumhq.selenium:selenium-grid` from 4.38.0 to 4.39.0
- [Release notes](https://github.com/SeleniumHQ/selenium/releases)
- [Commits](https://github.com/SeleniumHQ/selenium/compare/selenium-4.38.0...selenium-4.39.0)

---
updated-dependencies:
- dependency-name: org.seleniumhq.selenium:selenium-java
  dependency-version: 4.39.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.seleniumhq.selenium:selenium-grid
  dependency-version: 4.39.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
---
 pom.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pom.xml b/pom.xml
index a68733b58..6a3b9a7a4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -52,7 +52,7 @@
         <simplejavamail.version>8.12.6</simplejavamail.version>
         <jsonschemagenerator.version>4.38.0</jsonschemagenerator.version>
         <slf4j.version>2.0.17</slf4j.version>
-        <selenium.version>4.38.0</selenium.version>
+        <selenium.version>4.39.0</selenium.version>
     </properties>
 
     <profiles>

From e96ebeb84f4313a8e40cc5b62fcfb3cbe00239bb Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 16:45:29 +0100
Subject: [PATCH 14/20] refactor(external interpolation): renaming
 ConfigurationInterpolator to InPlaceInterpolator

---
 .../deserializers/interpolation/InterpolatedDeserializer.java | 2 +-
 ...onfigurationInterpolator.java => InPlaceInterpolator.java} | 2 +-
 .../java/io/github/giulong/spectrum/utils/Configuration.java  | 4 ++--
 spectrum/src/main/resources/yaml/configuration.default.yaml   | 2 +-
 ...tionInterpolatorTest.java => InPlaceInterpolatorTest.java} | 4 ++--
 5 files changed, 7 insertions(+), 7 deletions(-)
 rename spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/{ConfigurationInterpolator.java => InPlaceInterpolator.java} (97%)
 rename spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/{ConfigurationInterpolatorTest.java => InPlaceInterpolatorTest.java} (98%)

diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
index 126050cdc..c9dfe76c3 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/InterpolatedDeserializer.java
@@ -39,7 +39,7 @@ public String interpolate(final String value, final JsonParser jsonParser) {
                     .findFirst()
                     .orElse(value);
 
-            log.error("Chosen value: {} -> {}", currentName, interpolatedValue);
+            log.debug("Chosen value: {} -> {}", currentName, interpolatedValue);
             return interpolatedValue;
         }
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java
similarity index 97%
rename from spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
rename to spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java
index 87e580027..43e68967b 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolator.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java
@@ -12,7 +12,7 @@
 import lombok.extern.slf4j.Slf4j;
 
 @Slf4j
-public class ConfigurationInterpolator extends Interpolator {
+public class InPlaceInterpolator extends Interpolator {
 
     private static final Pattern PATTERN = Pattern.compile("(?<placeholder>\\$\\{(?<varName>[\\w.]+)(:-(?<defaultValue>[\\w~\\s-.:/\\\\=]*))?})");
 
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
index 247737892..2d101b271 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/utils/Configuration.java
@@ -16,8 +16,8 @@
 
 import io.github.giulong.spectrum.drivers.Driver;
 import io.github.giulong.spectrum.interfaces.JsonSchemaTypes;
-import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.ConfigurationInterpolator;
 import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.EnvironmentInterpolator;
+import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.InPlaceInterpolator;
 import io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.PropertiesInterpolator;
 import io.github.giulong.spectrum.utils.environments.Environment;
 import io.github.giulong.spectrum.utils.events.EventsConsumer;
@@ -107,7 +107,7 @@ public static class Interpolators {
             private PropertiesInterpolator properties;
 
             @JsonPropertyDescription("In-place configuration file interpolator")
-            private ConfigurationInterpolator configuration;
+            private InPlaceInterpolator inPlace;
         }
     }
 
diff --git a/spectrum/src/main/resources/yaml/configuration.default.yaml b/spectrum/src/main/resources/yaml/configuration.default.yaml
index 2909ecd79..66b13eb13 100644
--- a/spectrum/src/main/resources/yaml/configuration.default.yaml
+++ b/spectrum/src/main/resources/yaml/configuration.default.yaml
@@ -9,7 +9,7 @@ config:
       priority: 1 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
-    configuration: # In-place configuration file interpolator
+    inPlace: # In-place configuration file interpolator
       priority: 2 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       enabled: true
 
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolatorTest.java
similarity index 98%
rename from spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
rename to spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolatorTest.java
index 39cab1501..2954d2c06 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ConfigurationInterpolatorTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolatorTest.java
@@ -24,7 +24,7 @@
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 
-class ConfigurationInterpolatorTest {
+class InPlaceInterpolatorTest {
 
     private static final String VAR_IN_ENV = "varInEnv";
 
@@ -34,7 +34,7 @@ class ConfigurationInterpolatorTest {
     private JsonParser jsonParser;
 
     @InjectMocks
-    private ConfigurationInterpolator interpolator;
+    private InPlaceInterpolator interpolator;
 
     @BeforeAll
     public static void beforeAll() {

From df893594ce96df4c86b569e4a73dcb52e65d97dc Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 17:38:54 +0100
Subject: [PATCH 15/20] docs(external interpolation): adding the new section in
 gh pages

---
 docs/README.md | 158 ++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 155 insertions(+), 3 deletions(-)

diff --git a/docs/README.md b/docs/README.md
index 51ff56516..7aeb05b23 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -622,8 +622,53 @@ runtime:
 
 ## Values interpolation
 
-Plain values (not objects nor arrays) in `configuration*.yaml` and `data*.yaml`  can be interpolated with a dollar-string
-in one of these two ways, depending on the type needed as result. Let's suppose we have the variable `key = 123`:
+Plain values (not objects nor arrays) in `configuration*.yaml` and `data*.yaml` can be interpolated, meaning their value can be injected
+instead of being hardcoded. This is quite useful if you want to keep the same configuration files, while being able to tweak it at runtime, based
+on the execution environment for instance.
+
+There are a few ways to interpolate configuration keys:
+
+* [In-place interpolation](#in-place-interpolation): directly in the `configuration.yaml`
+* [Environment variables interpolation](#environment-variables-interpolation): injecting values from the current env
+* [System properties interpolation](#system-properties-interpolation): injecting values passed as system properties
+
+> 💡 **Tip**<br/>
+> You can mix all the available options, for example having some keys interpolated in-place, and some others injected from env vars and system properties.
+
+Each interpolator can be configured in the base `configuration.yaml` under the `config` node. Here you can see the internal
+[configuration.default.yaml]({{ site.repository_url }}/spectrum/src/main/resources/yaml/configuration.default.yaml){:target="_blank"}:
+
+{% include copyCode.html %}
+
+```yaml
+# Generic configuration. This node is read only from the base configuration.yaml
+config:
+  interpolators: # Configuration keys interpolators
+    environment: # Environment variables interpolator
+      priority: 0 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
+      prefix: spectrum # Variable prefix
+      delimiter: . # Variable tokens' delimiter
+    properties: # Properties interpolator
+      priority: 1 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
+      prefix: spectrum # Variable prefix
+      delimiter: . # Variable tokens' delimiter
+    inPlace: # In-place configuration file interpolator
+      priority: 2 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
+      enabled: true
+```
+
+You can see that each interpolator has a `priority`. That's an int value that specifies the resolution order:
+when a key is resolved by more than one interpolator, the one with the highest priority is used to inject the interpolated value.
+The other keys are explained in the corresponding sections.
+
+> ⚠️ **Overriding the `config` node**<br/>
+> You can customize the `config` node in the base `configuration.yaml` only. Overriding it in any other `configuration-<PROFILE>.yaml`
+> simply won't have any effect. This is needed since the `config` node is a *meta*-configuration that specifies how to read all the other keys.
+
+### In-place Interpolation
+
+You can interpolate values directly in the `configuration*.yaml` and `data*.yaml` with a dollar-string in one of the following two ways,
+depending on the type needed as result. Let's suppose we have the variable `key = 123`:
 
 | Needed type | Interpolation key | Result | Behaviour if not found                                       |
 |-------------|-------------------|--------|--------------------------------------------------------------|
@@ -746,7 +791,7 @@ runtime:
   profiles: ${active-profiles:-local}
 ```
 
-These are the variables already available in the [configuration.default.yaml]({{ site.repository_url }}/spectrum/src/main/resources/yaml/configuration.default.yaml){:
+These variables are already available in the [configuration.default.yaml]({{ site.repository_url }}/spectrum/src/main/resources/yaml/configuration.default.yaml){:
 target="_blank"}.
 You can add your own and even override the default ones in your `configuration*.yaml`:
 
@@ -754,10 +799,117 @@ You can add your own and even override the default ones in your `configuration*.
 |----------------------|------------------------------|------------------------------|
 | spectrum.profiles    | local                        | local                        |
 | spectrum.driver      | chrome                       | chrome                       |
+| spectrum.environment | local                        | local                        |
 | downloadsFolder      | ${user.dir}\target\downloads | ${user.dir}/target/downloads |
 | summaryReportOutput  | target/spectrum/summary      | target/spectrum/summary      |
 | testBookReportOutput | target/spectrum/testbook     | target/spectrum/testbook     |
 
+The in-place interpolator is enabled by default with the highest priority. You can disable it or change its priority with this configuration snippet:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    inPlace:
+      priority: 123
+      enabled: false
+```
+
+### Environment Variables Interpolation
+
+You can **avoid to specify keys directly in the yaml files** and interpolate values taken from environment variables
+by providing this configuration snippet:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    environment: { }
+```
+
+Providing an empty object as above, you'll leverage on the internal defaults, which are the following:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    environment:
+      priority: 0
+      prefix: spectrum
+      delimiter: .
+```
+
+This means every configuration key will be searched in env vars, with the `spectrum` prefix and words delimited by a dot.
+For instance, you can inject the `application.baseUrl` setting an env variable named `spectrum.application.baseUrl`.
+
+To give you another example, you can use this config to inject env vars like `application_baseUrl`:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    environment:
+      prefix: ''
+      delimiter: _
+```
+
+> ⚠️ **Priority**<br/>
+> Pay attention to the priority: by default, the `inPlace` interpolator takes precedence over this one.
+> This means that if you provide the same key in the yaml file, the env var will be ignored. You have to options to inject the env var:
+> * delete the hardcoded key
+> * set a higher priority in the environment interpolator
+
+### System Properties Interpolation
+
+You can **avoid to specify keys directly in the yaml files** and interpolate values taken from system properties
+by providing this configuration snippet:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    properties: { }
+```
+
+Providing an empty object as above, you'll leverage on the internal defaults, which are the following:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    properties:
+      priority: 1
+      prefix: spectrum
+      delimiter: .
+```
+
+This means every configuration key will be searched in system properties, with the `spectrum` prefix and words delimited by a dot.
+For instance, you can inject the `application.baseUrl` setting the system property `-Dspectrum.application.baseUrl`.
+
+To give you another example, you can use this config to inject system properties like `-Dapplication_baseUrl`:
+
+{% include copyCode.html %}
+
+```yaml
+config:
+  interpolators:
+    properties:
+      prefix: ''
+      delimiter: _
+```
+
+> ⚠️ **Priority**<br/>
+> Pay attention to the priority: by default, the `inPlace` interpolator takes precedence over this one.
+> This means that if you provide the same key in the yaml file, the system property will be ignored. You have to options to inject the system property:
+> * delete the hardcoded key
+> * set a higher priority in the properties interpolator
+
 ---
 
 ## Configuring the Driver

From f7644e40f51d0838f9381de5391af1f3d682b215 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 19:17:57 +0100
Subject: [PATCH 16/20] feat(external interpolation): introducing transformCase
 property for external interpolation, to allow for resolution of upper/lower
 case external vars

---
 .github/workflows/build.yml                   |  4 +--
 it/pom.xml                                    |  4 +--
 it/src/test/resources/configuration.yaml      |  1 +
 .../interpolators/ExternalInterpolator.java   | 33 +++++++++++++++++--
 .../resources/yaml/configuration.default.yaml |  2 ++
 .../ExternalInterpolatorTest.java             | 28 +++++++++++++++-
 6 files changed, 64 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 0b77f2593..07d195dc0 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -102,8 +102,8 @@ jobs:
       - name: Run browsers ITs
         shell: bash
         run: |
-          export spectrum_video_skipDuplicateFrames=false
-          export spectrum_application_baseUrl='https://the-internet.herokuapp.com/'
+          export SPECTRUM_VIDEO_SKIPDUPLICATEFRAMES=false
+          export SPECTRUM_APPLICATION_BASEURL='https://the-internet.herokuapp.com/'
           ./mvnw install:install-file -ntp -Dfile=$GITHUB_WORKSPACE/spectrum-${{ env.VERSION }}.jar -DgroupId=io.github.giulong -DartifactId=spectrum -Dversion=${{ env.VERSION }} -Dpackaging=jar
           ./mvnw install -DskipSign -Dmaven.plugin.validation=NONE ${{ matrix.directives }} -ntp -P ${{ matrix.profiles }}
 
diff --git a/it/pom.xml b/it/pom.xml
index 53a651900..f16d69ee5 100644
--- a/it/pom.xml
+++ b/it/pom.xml
@@ -55,8 +55,8 @@
                 <artifactId>maven-failsafe-plugin</artifactId>
                 <configuration>
                     <environmentVariables>
-                        <spectrum_video_skipDuplicateFrames>false</spectrum_video_skipDuplicateFrames>
-                        <spectrum_application_baseUrl>https://the-internet.herokuapp.com/</spectrum_application_baseUrl>
+                        <SPECTRUM_VIDEO_SKIPDUPLICATEFRAMES>false</SPECTRUM_VIDEO_SKIPDUPLICATEFRAMES>
+                        <SPECTRUM_APPLICATION_BASEURL>https://the-internet.herokuapp.com/</SPECTRUM_APPLICATION_BASEURL>
                     </environmentVariables>
                     <systemPropertyVariables>
                         <spectrum.application.baseUrl>overridden by the env variable above</spectrum.application.baseUrl>
diff --git a/it/src/test/resources/configuration.yaml b/it/src/test/resources/configuration.yaml
index e5cf1473f..55a8dfed6 100644
--- a/it/src/test/resources/configuration.yaml
+++ b/it/src/test/resources/configuration.yaml
@@ -3,6 +3,7 @@ config:
     environment:
       priority: 10
       delimiter: _
+      transformCase: upper
     properties: { }
 
 application:
diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java
index e65619895..e63fe0116 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolator.java
@@ -9,9 +9,12 @@
 import java.util.function.Function;
 
 import com.fasterxml.jackson.annotation.JsonPropertyDescription;
+import com.fasterxml.jackson.annotation.JsonValue;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonStreamContext;
 
+import lombok.AllArgsConstructor;
+import lombok.Generated;
 import lombok.Getter;
 import lombok.extern.slf4j.Slf4j;
 
@@ -27,6 +30,10 @@ public abstract class ExternalInterpolator extends Interpolator {
     @JsonPropertyDescription("Variable tokens' delimiter")
     private String delimiter;
 
+    @SuppressWarnings("unused")
+    @JsonPropertyDescription("Function to specify how to transform the original camelCase of the key to match the external variable to search")
+    private TransformCase transformCase;
+
     public abstract Function<String, String> getConsumer();
 
     @Override
@@ -40,11 +47,13 @@ public Optional<String> findVariableFor(final String value, final JsonParser jso
                 .stream()
                 .filter(Objects::nonNull)
                 .collect(joining(delimiter));
-        log.trace("{} is looking for {}", className, keyPath);
 
-        final String key = getConsumer().apply(keyPath);
+        final String transformedKeyPath = transformCase.getFunction().apply(keyPath);
+        log.trace("{} is looking for {}", className, transformedKeyPath);
+
+        final String key = getConsumer().apply(transformedKeyPath);
         if (key != null) {
-            log.debug("{} found {} = {}", className, keyPath, key);
+            log.debug("{} found {} = {}", className, transformedKeyPath, key);
             return Optional.of(key);
         }
 
@@ -59,4 +68,22 @@ void getKeyPathTokens(final List<String> accumulator, final JsonStreamContext co
             accumulator.add(context.getCurrentName());
         }
     }
+
+    @Getter
+    @AllArgsConstructor
+    enum TransformCase {
+
+        NONE("none", s -> s),
+        LOWER("lower", String::toLowerCase),
+        UPPER("upper", String::toUpperCase);
+
+        private final String value;
+        private final Function<String, String> function;
+
+        @JsonValue
+        @Generated
+        public String getValue() {
+            return value;
+        }
+    }
 }
diff --git a/spectrum/src/main/resources/yaml/configuration.default.yaml b/spectrum/src/main/resources/yaml/configuration.default.yaml
index 66b13eb13..ad2516115 100644
--- a/spectrum/src/main/resources/yaml/configuration.default.yaml
+++ b/spectrum/src/main/resources/yaml/configuration.default.yaml
@@ -5,10 +5,12 @@ config:
       priority: 0 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
+      transformCase: none # Function to specify how to transform the original camelCase of the key to match the external variable to search
     properties: # Properties interpolator
       priority: 1 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
+      transformCase: none # Function to specify how to transform the original camelCase of the key to match the external variable to search
     inPlace: # In-place configuration file interpolator
       priority: 2 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       enabled: true
diff --git a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java
index 0a87ade0a..6f64cca10 100644
--- a/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java
+++ b/spectrum/src/test/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/ExternalInterpolatorTest.java
@@ -1,5 +1,8 @@
 package io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators;
 
+import static io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.ExternalInterpolator.TransformCase.LOWER;
+import static io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.ExternalInterpolator.TransformCase.NONE;
+import static io.github.giulong.spectrum.internals.jackson.deserializers.interpolation.interpolators.ExternalInterpolator.TransformCase.UPPER;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.mockito.Mockito.inOrder;
 import static org.mockito.Mockito.verifyNoInteractions;
@@ -51,9 +54,11 @@ class ExternalInterpolatorTest {
     void beforeEach() {
         Reflections.setField("prefix", interpolator, "prefix");
         Reflections.setField("delimiter", interpolator, ".");
+        Reflections.setField("transformCase", interpolator, UPPER);
 
         Reflections.setField("prefix", interpolatorNotFound, "prefix");
         Reflections.setField("delimiter", interpolatorNotFound, ".");
+        Reflections.setField("transformCase", interpolatorNotFound, UPPER);
     }
 
     @Test
@@ -71,7 +76,7 @@ void findVariableFor() {
         when(context.getParent()).thenReturn(null);
         when(jsonParser.getParsingContext()).thenReturn(context);
 
-        assertEquals(Optional.of("prefixFound"), interpolator.findVariableFor(value, jsonParser));
+        assertEquals(Optional.of("PREFIXFound"), interpolator.findVariableFor(value, jsonParser));
     }
 
     @Test
@@ -107,6 +112,27 @@ void getKeyPathTokens() {
         verifyNoMoreInteractions(grandParentContext);
     }
 
+    @Test
+    @DisplayName("TransformCase none should return the original string provided")
+    void transformCaseNone() {
+        final String string = "string";
+        assertEquals(string, NONE.getFunction().apply(string));
+    }
+
+    @Test
+    @DisplayName("TransformCase lower should return the provided string lowercased")
+    void transformCaseLower() {
+        final String string = "string";
+        assertEquals(string.toLowerCase(), LOWER.getFunction().apply(string));
+    }
+
+    @Test
+    @DisplayName("TransformCase upper should return the provided string uppercased")
+    void transformCaseUpper() {
+        final String string = "string";
+        assertEquals(string.toUpperCase(), UPPER.getFunction().apply(string));
+    }
+
     private static final class DummyExternalInterpolator extends ExternalInterpolator {
 
         @Override

From 838497021535eeba93395798b43425dee1f72a3d Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 19:33:34 +0100
Subject: [PATCH 17/20] docs(external interpolation): adding transformCase
 property description with examples

---
 docs/README.md | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/docs/README.md b/docs/README.md
index 7aeb05b23..65bceb138 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -648,10 +648,12 @@ config:
       priority: 0 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
+      transformCase: none # Function to specify how to transform the original camelCase of the key to match the external variable to search
     properties: # Properties interpolator
       priority: 1 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       prefix: spectrum # Variable prefix
       delimiter: . # Variable tokens' delimiter
+      transformCase: none # Function to specify how to transform the original camelCase of the key to match the external variable to search
     inPlace: # In-place configuration file interpolator
       priority: 2 # Sets the order of evaluation of this interpolator among others. Higher priority wins.
       enabled: true
@@ -840,12 +842,13 @@ config:
       priority: 0
       prefix: spectrum
       delimiter: .
+      transformCase: none
 ```
 
 This means every configuration key will be searched in env vars, with the `spectrum` prefix and words delimited by a dot.
 For instance, you can inject the `application.baseUrl` setting an env variable named `spectrum.application.baseUrl`.
 
-To give you another example, you can use this config to inject env vars like `application_baseUrl`:
+To give you another example, you can use this config to inject env vars like `APPLICATION_BASEURL`:
 
 {% include copyCode.html %}
 
@@ -855,8 +858,17 @@ config:
     environment:
       prefix: ''
       delimiter: _
+      transformCase: upper
 ```
 
+Allowed values for the `transformCase` property are:
+
+| Value   | Description                                                                       | Example             |
+|---------|-----------------------------------------------------------------------------------|---------------------|
+| `none`  | searches a key with the same case of the property, which is `camelCase` (default) | application.baseUrl |
+| `lower` | searches a lowercase key                                                          | application.baseurl |
+| `upper` | searches a uppercase key                                                          | APPLICATION.BASEURL |
+
 > ⚠️ **Priority**<br/>
 > Pay attention to the priority: by default, the `inPlace` interpolator takes precedence over this one.
 > This means that if you provide the same key in the yaml file, the env var will be ignored. You have to options to inject the env var:
@@ -887,12 +899,13 @@ config:
       priority: 1
       prefix: spectrum
       delimiter: .
+      transformCase: none
 ```
 
 This means every configuration key will be searched in system properties, with the `spectrum` prefix and words delimited by a dot.
 For instance, you can inject the `application.baseUrl` setting the system property `-Dspectrum.application.baseUrl`.
 
-To give you another example, you can use this config to inject system properties like `-Dapplication_baseUrl`:
+To give you another example, you can use this config to inject system properties like `-DAPPLICATION_BASEURL`:
 
 {% include copyCode.html %}
 
@@ -902,8 +915,17 @@ config:
     properties:
       prefix: ''
       delimiter: _
+      transformCase: upper
 ```
 
+Allowed values for the `transformCase` property are:
+
+| Value   | Description                                                                       | Example             |
+|---------|-----------------------------------------------------------------------------------|---------------------|
+| `none`  | searches a key with the same case of the property, which is `camelCase` (default) | application.baseUrl |
+| `lower` | searches a lowercase key                                                          | application.baseurl |
+| `upper` | searches a uppercase key                                                          | APPLICATION.BASEURL |
+
 > ⚠️ **Priority**<br/>
 > Pay attention to the priority: by default, the `inPlace` interpolator takes precedence over this one.
 > This means that if you provide the same key in the yaml file, the system property will be ignored. You have to options to inject the system property:

From 96c09a2d722e116c0850094103db436adaadaaeb Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 19:37:51 +0100
Subject: [PATCH 18/20] build: adding paths-ignore to codeql gh action

---
 .github/workflows/codeql.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index eb12451b6..c95ce3134 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -3,6 +3,7 @@ name: CodeQL
 on:
   push:
     branches: [ "develop", "feature/**", "bugfix/**" ]
+    paths-ignore: [ '.mvn/**', 'mvnw', 'mvnw.cmd', '.run/**', 'docs/**', '.editorconfig', '.gitignore', '**.md' ]
 
 jobs:
   analyze:

From 04e957797e58f3e20292484ea694bd6113136dc2 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 19:53:12 +0100
Subject: [PATCH 19/20] refactor: minor InPlaceInterpolator code cleaning,
 removing a redundant if condition

---
 .../interpolation/interpolators/InPlaceInterpolator.java     | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java
index 43e68967b..a9f2743d1 100644
--- a/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java
+++ b/spectrum/src/main/java/io/github/giulong/spectrum/internals/jackson/deserializers/interpolation/interpolators/InPlaceInterpolator.java
@@ -44,10 +44,7 @@ public Optional<String> findVariableFor(final String value, final JsonParser jso
                 }
             } else {
                 log.trace("Interpolated value for key '{}: {}' -> '{}'", currentName, value, interpolatedValue);
-
-                if (PATTERN.matcher(interpolatedValue).find()) {
-                    interpolatedValue = findVariableFor(interpolatedValue, jsonParser).orElse(value);
-                }
+                interpolatedValue = findVariableFor(interpolatedValue, jsonParser).orElse(interpolatedValue);
             }
         }
 

From ff6491e0e7f44fa1a47db657c0479725f49d17c0 Mon Sep 17 00:00:00 2001
From: Giulio Longfils <giuliolongfils@gmail.com>
Date: Mon, 8 Dec 2025 21:38:06 +0100
Subject: [PATCH 20/20] docs: minor change

---
 docs/README.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/docs/README.md b/docs/README.md
index 65bceb138..437ebfae1 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -820,7 +820,7 @@ config:
 
 ### Environment Variables Interpolation
 
-You can **avoid to specify keys directly in the yaml files** and interpolate values taken from environment variables
+You can **avoid specifying keys directly in the yaml files** and interpolate values taken from environment variables
 by providing this configuration snippet:
 
 {% include copyCode.html %}
@@ -877,7 +877,7 @@ Allowed values for the `transformCase` property are:
 
 ### System Properties Interpolation
 
-You can **avoid to specify keys directly in the yaml files** and interpolate values taken from system properties
+You can **avoid specifying keys directly in the yaml files** and interpolate values taken from system properties
 by providing this configuration snippet:
 
 {% include copyCode.html %}