diff --git a/tests/r8-synthetic.rs b/tests/r8-synthetic.rs
new file mode 100644
index 0000000..97d0b68
--- /dev/null
+++ b/tests/r8-synthetic.rs
@@ -0,0 +1,152 @@
+//! Tests for R8 synthetic / lambda method retracing fixtures.
+//!
+//! These tests are based on the R8 retrace test suite from:
+//! src/test/java/com/android/tools/r8/retrace/stacktraces/
+
+use proguard::{ProguardCache, ProguardMapper, ProguardMapping};
+
+// =============================================================================
+// SyntheticLambdaMethodStackTrace
+// =============================================================================
+
+const SYNTHETIC_LAMBDA_METHOD_MAPPING: &str = "\
+# {'id':'com.android.tools.r8.mapping','version':'1.0'}
+example.Main -> example.Main:
+    1:1:void main(java.lang.String[]):123 -> main
+example.Foo -> a.a:
+    5:5:void lambda$main$0():225 -> a
+    3:3:void runIt():218 -> b
+    2:2:void main():223 -> c
+example.Foo$$ExternalSyntheticLambda0 -> a.b:
+    void run(example.Foo) -> a
+      # {'id':'com.android.tools.r8.synthesized'}
+";
+
+#[test]
+fn test_synthetic_lambda_method_stacktrace() {
+    let input = "\
+Exception in thread \"main\" java.lang.NullPointerException
+  at a.a.a(a.java:5)
+  at a.b.a(Unknown Source)
+  at a.a.b(a.java:3)
+  at a.a.c(a.java:2)
+  at example.Main.main(Main.java:1)
+";
+
+    // Note: this crate prints 4 spaces before each remapped frame.
+    // Also, when no line info is available, it will output :0.
+    let expected = "\
+Exception in thread \"main\" java.lang.NullPointerException
+    at example.Foo.lambda$main$0(Foo.java:225)
+    at example.Foo.runIt(Foo.java:218)
+    at example.Foo.main(Foo.java:223)
+    at example.Main.main(Main.java:123)
+";
+
+    let mapper = ProguardMapper::from(SYNTHETIC_LAMBDA_METHOD_MAPPING);
+    let actual = mapper.remap_stacktrace(input).unwrap();
+    assert_eq!(actual.trim(), expected.trim());
+
+    let mapping = ProguardMapping::new(SYNTHETIC_LAMBDA_METHOD_MAPPING.as_bytes());
+    let mut buf = Vec::new();
+    ProguardCache::write(&mapping, &mut buf).unwrap();
+    let cache = ProguardCache::parse(&buf).unwrap();
+    cache.test();
+
+    let actual = cache.remap_stacktrace(input).unwrap();
+    assert_eq!(actual.trim(), expected.trim());
+}
+
+// =============================================================================
+// SyntheticLambdaMethodWithInliningStackTrace
+// =============================================================================
+
+const SYNTHETIC_LAMBDA_METHOD_WITH_INLINING_MAPPING: &str = "\
+# {'id':'com.android.tools.r8.mapping','version':'1.0'}
+example.Main -> example.Main:
+    1:1:void main(java.lang.String[]):123 -> main
+example.Foo -> a.a:
+    3:3:void runIt():218 -> b
+    2:2:void main():223 -> c
+example.Foo$$ExternalSyntheticLambda0 -> a.b:
+    4:4:void example.Foo.lambda$main$0():225 -> a
+    4:4:void run(example.Foo):0 -> a
+      # {'id':'com.android.tools.r8.synthesized'}
+";
+
+#[test]
+fn test_synthetic_lambda_method_with_inlining_stacktrace() {
+    let input = "\
+Exception in thread \"main\" java.lang.NullPointerException
+  at a.b.a(Unknown Source:4)
+  at a.a.b(a.java:3)
+  at a.a.c(a.java:2)
+  at example.Main.main(Main.java:1)
+";
+
+    let expected = "\
+Exception in thread \"main\" java.lang.NullPointerException
+    at example.Foo.lambda$main$0(Foo.java:225)
+    at example.Foo.runIt(Foo.java:218)
+    at example.Foo.main(Foo.java:223)
+    at example.Main.main(Main.java:123)
+";
+
+    let mapper = ProguardMapper::from(SYNTHETIC_LAMBDA_METHOD_WITH_INLINING_MAPPING);
+    let actual = mapper.remap_stacktrace(input).unwrap();
+    assert_eq!(actual.trim(), expected.trim());
+
+    let mapping = ProguardMapping::new(SYNTHETIC_LAMBDA_METHOD_WITH_INLINING_MAPPING.as_bytes());
+    let mut buf = Vec::new();
+    ProguardCache::write(&mapping, &mut buf).unwrap();
+    let cache = ProguardCache::parse(&buf).unwrap();
+    cache.test();
+
+    let actual = cache.remap_stacktrace(input).unwrap();
+    assert_eq!(actual.trim(), expected.trim());
+}
+
+// =============================================================================
+// MovedSynthetizedInfoStackTraceTest
+// =============================================================================
+
+const MOVED_SYNTHETIZED_INFO_MAPPING: &str = "\
+# { id: 'com.android.tools.r8.mapping', version: '2.2' }
+com.android.tools.r8.BaseCommand$Builder -> foo.bar:
+    1:1:void inlinee(java.util.Collection):0:0 -> inlinee$synthetic
+    1:1:void inlinee$synthetic(java.util.Collection):0:0 -> inlinee$synthetic
+    2:2:void inlinee(java.util.Collection):206:206 -> inlinee$synthetic
+    2:2:void inlinee$synthetic(java.util.Collection):0:0 -> inlinee$synthetic
+      # {\"id\":\"com.android.tools.r8.synthesized\"}
+    4:4:void inlinee(java.util.Collection):208:208 -> inlinee$synthetic
+    4:4:void inlinee$synthetic(java.util.Collection):0 -> inlinee$synthetic
+    7:7:void error(origin.Origin,java.lang.Throwable):363:363 -> inlinee$synthetic
+    7:7:void inlinee(java.util.Collection):210 -> inlinee$synthetic
+    7:7:void inlinee$synthetic(java.util.Collection):0:0 -> inlinee$synthetic
+";
+
+#[test]
+fn test_moved_synthetized_info_stacktrace() {
+    let input = "\
+java.lang.RuntimeException: foobar
+	at foo.bar.inlinee$synthetic(BaseCommand.java:2)
+";
+
+    let expected = "\
+java.lang.RuntimeException: foobar
+    at com.android.tools.r8.BaseCommand$Builder.inlinee(BaseCommand.java:206)
+";
+
+    let mapper = ProguardMapper::from(MOVED_SYNTHETIZED_INFO_MAPPING);
+    let actual = mapper.remap_stacktrace(input).unwrap();
+    assert_eq!(actual.trim(), expected.trim());
+
+    let mapping = ProguardMapping::new(MOVED_SYNTHETIZED_INFO_MAPPING.as_bytes());
+    let mut buf = Vec::new();
+    ProguardCache::write(&mapping, &mut buf).unwrap();
+    let cache = ProguardCache::parse(&buf).unwrap();
+    cache.test();
+
+    let actual = cache.remap_stacktrace(input).unwrap();
+    assert_eq!(actual.trim(), expected.trim());
+}