diff --git a/Sources/ConfidentialCore/Models/Configuration/Configuration.swift b/Sources/ConfidentialCore/Models/Configuration/Configuration.swift
index cdbe835..5509da7 100644
--- a/Sources/ConfidentialCore/Models/Configuration/Configuration.swift
+++ b/Sources/ConfidentialCore/Models/Configuration/Configuration.swift
@@ -26,9 +26,9 @@ public struct Configuration: Equatable, Decodable {
         let container = try decoder.container(keyedBy: CodingKeys.self)
         self = .init(
             algorithm: try container.decode([String].self, forKey: .algorithm)[...],
-            defaultAccessModifier: try? container.decodeIfPresent(String.self, forKey: .defaultAccessModifier),
-            defaultNamespace: try? container.decodeIfPresent(String.self, forKey: .defaultNamespace),
-            implementationOnlyImport: try? container.decodeIfPresent(Bool.self, forKey: .implementationOnlyImport),
+            defaultAccessModifier: try container.decodeIfPresent(String.self, forKey: .defaultAccessModifier),
+            defaultNamespace: try container.decodeIfPresent(String.self, forKey: .defaultNamespace),
+            implementationOnlyImport: try container.decodeIfPresent(Bool.self, forKey: .implementationOnlyImport),
             secrets: try container.decode([Secret].self, forKey: .secrets)[...]
         )
     }
diff --git a/Tests/ConfidentialCoreTests/Models/Configuration/ConfigurationTests.swift b/Tests/ConfidentialCoreTests/Models/Configuration/ConfigurationTests.swift
index 4234bd0..8964806 100644
--- a/Tests/ConfidentialCoreTests/Models/Configuration/ConfigurationTests.swift
+++ b/Tests/ConfidentialCoreTests/Models/Configuration/ConfigurationTests.swift
@@ -56,6 +56,49 @@ final class ConfigurationTests: XCTestCase {
         )
     }
 
+    func test_givenInvalidJSONEncodedConfiguration_whenDecodeWithJSONDecoder_thenThrowsError() {
+        // given
+        let invalidConfigurations = [
+            """
+            {
+              "algorithm": ["compress using lz4"]
+            }
+            """,
+            """
+            {
+              "secrets": [{ "name": "secret", "value": "value" }]
+            }
+            """,
+            """
+            {
+              "algorithm": ["compress using lz4"],
+              "defaultAccessModifier": [],
+              "secrets": [{ "name": "secret", "value": "value" }]
+            }
+            """,
+            """
+            {
+              "algorithm": ["compress using lz4"],
+              "defaultNamespace": [],
+              "secrets": [{ "name": "secret", "value": "value" }]
+            }
+            """,
+            """
+            {
+              "algorithm": ["compress using lz4"],
+              "implementationOnlyImport": 1,
+              "secrets": [{ "name": "secret", "value": "value" }]
+            }
+            """
+        ].map { ($0, $0.data(using: .utf8)!) }
+        let decoder = JSONDecoder()
+
+        // when & then
+        for (json, jsonData) in invalidConfigurations {
+            XCTAssertThrowsError(try decoder.decode(Configuration.self, from: jsonData), json)
+        }
+    }
+
     func test_givenSecretSingleValue_whenJSONEncodeUnderlyingValue_thenResultEqualsJSONEncodedAssociatedValue() throws {
         // given
         let associatedValue = "test"