2 files changed, 31 insertions, 0 deletions
diff --git a/internal/engine/tick.go b/internal/engine/tick.go
index 68dd54f..8c64cdd 100644
--- a/internal/engine/tick.go
+++ b/internal/engine/tick.go
@@ -4,6 +4,7 @@ package engine
 
 import (
 	"math/rand"
+	"reflect"
 	"sort"
 	"sync"
 	"time"
@@ -171,6 +172,16 @@ func ValuesEqual(a, b any) bool {
 	if aok && bok {
 		return ai == bi
 	}
+	// == panics when both operands share an uncomparable dynamic type (a
+	// YAML list or map used as a flag value). Fall back to DeepEqual so a
+	// tick system cannot panic on authored content.
+	ta, tb := reflect.TypeOf(a), reflect.TypeOf(b)
+	if ta != tb {
+		return false
+	}
+	if ta != nil && !ta.Comparable() {
+		return reflect.DeepEqual(a, b)
+	}
 	return a == b
 }
 
diff --git a/internal/engine/tick_values_test.go b/internal/engine/tick_values_test.go
new file mode 100644
index 0000000..4c704bb
--- /dev/null
+++ b/internal/engine/tick_values_test.go
@@ -0,0 +1,20 @@
+package engine
+
+import "testing"
+
+// TestValuesEqualUncomparableDoesNotPanic: a YAML list/map flag value must not
+// panic a tick system when compared (== panics on uncomparable dynamic types).
+func TestValuesEqualUncomparableDoesNotPanic(t *testing.T) {
+	if !ValuesEqual([]any{1, 2}, []any{1, 2}) {
+		t.Fatal("equal slices should compare equal")
+	}
+	if ValuesEqual([]any{1, 2}, []any{1, 3}) {
+		t.Fatal("different slices should not compare equal")
+	}
+	if !ValuesEqual(map[string]any{"x": 1}, map[string]any{"x": 1}) {
+		t.Fatal("equal maps should compare equal")
+	}
+	if ValuesEqual(map[string]any{"x": 1}, map[string]any{"x": 2}) {
+		t.Fatal("different maps should not compare equal")
+	}
+}