diff --git a/.ameba.yml b/.ameba.yml
index 47647e8e1..ade340122 100644
--- a/.ameba.yml
+++ b/.ameba.yml
@@ -1,5 +1,18 @@
+Documentation/DocumentationAdmonition:
+  Enabled: false
+
+Naming/RescuedExceptionsVariableName:
+  Excluded:
+    - spec/examples_spec.cr
+
 Metrics/CyclomaticComplexity:
   Enabled: false
 
 Lint/NotNil:
   Enabled: false
+
+Lint/Typos:
+  Enabled: false
+
+Lint/UselessAssign:
+  ExcludeTypeDeclarations: true
diff --git a/spec/examples_spec.cr b/spec/examples_spec.cr
index bebf2e8be..b1e84243e 100644
--- a/spec/examples_spec.cr
+++ b/spec/examples_spec.cr
@@ -59,7 +59,7 @@ Dir
           rescue item : Mint::Error
             fail item.to_terminal.to_s
           rescue item
-            fail item.to_s + '\n' + item.backtrace.join('\n')
+            fail "#{item}\n#{item.backtrace.join('\n')}"
           end
         end
       end
diff --git a/spec/spec_helper.cr b/spec/spec_helper.cr
index b1ff03063..3dff95e1d 100644
--- a/spec/spec_helper.cr
+++ b/spec/spec_helper.cr
@@ -4,13 +4,13 @@ ENV["SPEC"] = "TRUE"
 MINT_ENV["TEST"] = "TRUE"
 
 def diff(a, b)
-  file1 = File.tempfile do |f|
-    f.puts a.strip
-    f.flush
+  file1 = File.tempfile do |io|
+    io.puts a.strip
+    io.flush
   end
-  file2 = File.tempfile do |f|
-    f.puts b
-    f.flush
+  file2 = File.tempfile do |io|
+    io.puts b
+    io.flush
   end
 
   io = IO::Memory.new
diff --git a/src/ast/node.cr b/src/ast/node.cr
index 58c8945ce..1078ac26f 100644
--- a/src/ast/node.cr
+++ b/src/ast/node.cr
@@ -99,8 +99,8 @@ module Mint
       def self.compute_location(file : Parser::File, from, to)
         # TODO: avoid creating this array for every (initial) call to `Node#location`
         lines = [0]
-        file.contents.each_char_with_index do |ch, i|
-          lines << i + 1 if ch == '\n'
+        file.contents.each_char_with_index do |char, i|
+          lines << i + 1 if char == '\n'
         end
 
         Location.new(
diff --git a/src/builder.cr b/src/builder.cr
index cbb190e20..8a2c2986c 100644
--- a/src/builder.cr
+++ b/src/builder.cr
@@ -204,7 +204,7 @@ module Mint
       workspace.watch
     end
 
-    def get_service_worker_utils
+    def service_worker_utils
       Assets.read("sw-utils.js")
     end
 
@@ -214,7 +214,7 @@ module Mint
 
     def service_worker(artifacts, relative, optimize)
       worker = ServiceWorker.new(artifacts, relative, optimize)
-      "#{get_service_worker_utils}#{worker}"
+      "#{service_worker_utils}#{worker}"
     end
   end
 end
diff --git a/src/utils/service_worker.cr b/src/utils/service_worker.cr
index 3c146ad79..c03b3f77d 100644
--- a/src/utils/service_worker.cr
+++ b/src/utils/service_worker.cr
@@ -35,16 +35,14 @@ module Mint
       files
         .reduce(OpenSSL::Digest.new("SHA256")) do |digest, file|
           digest.file(file)
-        end.final.hexstring
+        end.hexfinal
     end
 
-    def get_routes : String
+    def build_routes : String
       routes = Mint::Compiler
         .new(TypeChecker.check(@artifacts.ast))
         .compile_service_worker(@artifacts.ast.routes)
-        .map do |node|
-          "...#{node}"
-        end
+        .map { |node| "...#{node}" }
 
       @js.const("routes", "[#{routes.join(", ")}]")
     end
diff --git a/src/utils/service_worker.ecr b/src/utils/service_worker.ecr
index 935501be9..608fd4b4e 100644
--- a/src/utils/service_worker.ecr
+++ b/src/utils/service_worker.ecr
@@ -2,7 +2,7 @@ const CACHE = '<%= calculate_hash %>'
 const PRECACHE_URLS = [
 <%= precache_urls.indent(2) %>
 ]
-<%= get_routes %>
+<%= build_routes %>
 
 // On install precache all static resources
 self.addEventListener('install', event => {