diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 43e3ec251..91d790897 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -88,7 +88,7 @@ jobs:
         node-version: ${{ env.NODE_VERSION }}
 
     - name: Run tests
-      run: EFFEKT_VALGRIND=1 sbt clean test
+      run: EFFEKT_VALGRIND=1 EFFEKT_DEBUG=1 sbt clean test
 
     - name: Assemble fully optimized js file
       run: sbt effektJS/fullOptJS
diff --git a/effekt/jvm/src/main/scala/effekt/Runner.scala b/effekt/jvm/src/main/scala/effekt/Runner.scala
index adfd243cc..329679e0b 100644
--- a/effekt/jvm/src/main/scala/effekt/Runner.scala
+++ b/effekt/jvm/src/main/scala/effekt/Runner.scala
@@ -332,8 +332,9 @@ object LLVMRunner extends Runner[String] {
     val executableFile = basePath
     var gccArgs = Seq(gcc, gccMainFile, "-o", executableFile, objPath) ++ linkedLibraries
 
-    if (C.config.debug()) gccArgs ++= Seq("-fsanitize=address,undefined", "-fstack-protector-all", "-Og", "-g", "-Wall", "-Wextra")
+    if (C.config.debug()) gccArgs ++= Seq("-g", "-Wall", "-Wextra", "-Werror")
     if (C.config.valgrind()) gccArgs ++= Seq("-O0", "-g")
+    else if (C.config.debug()) gccArgs ++= Seq("-fsanitize=address,undefined", "-fstack-protector-all")
 
     exec(gccArgs: _*)
 
diff --git a/effekt/jvm/src/test/scala/effekt/EffektTests.scala b/effekt/jvm/src/test/scala/effekt/EffektTests.scala
index f947693b4..d8de0ba1f 100644
--- a/effekt/jvm/src/test/scala/effekt/EffektTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/EffektTests.scala
@@ -20,6 +20,9 @@ trait EffektTests extends munit.FunSuite {
   // Whether to execute using valgrind
   def valgrind = false
 
+  // Whether to execute using debug mode
+  def debug = false
+
   def output: File = new File(".") / "out" / "tests" / getClass.getName.toLowerCase
 
   // The sources of all testfiles are stored here:
@@ -64,6 +67,7 @@ trait EffektTests extends munit.FunSuite {
       "--out", output.getPath,
     )
     if (valgrind) options = options :+ "--valgrind"
+    if (debug) options = options :+ "--debug"
     val configs = compiler.createConfig(options)
     configs.verify()
 
diff --git a/effekt/jvm/src/test/scala/effekt/LLVMTests.scala b/effekt/jvm/src/test/scala/effekt/LLVMTests.scala
index 50b77aa70..8d8e50c6b 100644
--- a/effekt/jvm/src/test/scala/effekt/LLVMTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/LLVMTests.scala
@@ -11,6 +11,7 @@ class LLVMTests extends EffektTests {
   def backendName = "llvm"
 
   override def valgrind = sys.env.get("EFFEKT_VALGRIND").nonEmpty
+  override def debug = sys.env.get("EFFEKT_DEBUG").nonEmpty
 
   override lazy val positives: List[File] = List(
     examplesDir / "llvm",
diff --git a/effekt/jvm/src/test/scala/effekt/StdlibTests.scala b/effekt/jvm/src/test/scala/effekt/StdlibTests.scala
index 76dd5c5dd..1086dbc0f 100644
--- a/effekt/jvm/src/test/scala/effekt/StdlibTests.scala
+++ b/effekt/jvm/src/test/scala/effekt/StdlibTests.scala
@@ -36,6 +36,7 @@ class StdlibLLVMTests extends StdlibTests {
   def backendName: String = "llvm"
 
   override def valgrind = sys.env.get("EFFEKT_VALGRIND").nonEmpty
+  override def debug = sys.env.get("EFFEKT_DEBUG").nonEmpty
 
   override def ignored: List[File] = List(
     // Toplevel let-bindings (for ANSI-color-codes in output) not supported