diff --git a/src/main/java/com/mojang/datafixers/optics/Affine.java b/src/main/java/com/mojang/datafixers/optics/Affine.java
index 9f7e4fee..4b64505a 100644
--- a/src/main/java/com/mojang/datafixers/optics/Affine.java
+++ b/src/main/java/com/mojang/datafixers/optics/Affine.java
@@ -32,9 +32,7 @@ default <P extends K2> FunctionType<App2<P, A, B>, App2<P, S, T>> eval(final App
         return input -> cartesian.dimap(
             cocartesian.left(cartesian.rmap(cartesian.<A, B, S>first(input), p -> set(p.getFirst(), p.getSecond()))),
             (S s) -> preview(s).map(Either::right, a -> Either.left(Pair.of(a, s))),
-            (Either<T, T> e) -> {
-                return e.map(Function.identity(), Function.identity());
-            }
+            Either::unwrap
         );
     }
 
diff --git a/src/main/java/com/mojang/serialization/Codec.java b/src/main/java/com/mojang/serialization/Codec.java
index 3a570a89..47a4a1ad 100644
--- a/src/main/java/com/mojang/serialization/Codec.java
+++ b/src/main/java/com/mojang/serialization/Codec.java
@@ -132,7 +132,7 @@ static <T> Codec<T> withAlternative(final Codec<T> primary, final Codec<? extend
             primary,
             alternative
         ).xmap(
-            either -> either.map(v -> v, v -> v),
+            Either::unwrap,
             Either::left
         );
     }
diff --git a/src/main/java/com/mojang/serialization/DataResult.java b/src/main/java/com/mojang/serialization/DataResult.java
index e2504df1..b2531817 100644
--- a/src/main/java/com/mojang/serialization/DataResult.java
+++ b/src/main/java/com/mojang/serialization/DataResult.java
@@ -126,6 +126,12 @@ default DataResult<R> addLifecycle(final Lifecycle lifecycle) {
         return setLifecycle(lifecycle().add(lifecycle));
     }
 
+    boolean isSuccess();
+
+    default boolean isError() {
+        return !isSuccess();
+    }
+
     record Success<R>(R value, Lifecycle lifecycle) implements DataResult<R> {
         @Override
         public Optional<R> result() {
@@ -223,6 +229,11 @@ public DataResult<R> setLifecycle(final Lifecycle lifecycle) {
             return new Success<>(value, lifecycle);
         }
 
+        @Override
+        public boolean isSuccess() {
+            return true;
+        }
+
         @Override
         public String toString() {
             return "DataResult.Success[" + value + "]";
@@ -361,6 +372,11 @@ public Error<R> setLifecycle(final Lifecycle lifecycle) {
             return new Error<>(messageSupplier, partialValue, lifecycle);
         }
 
+        @Override
+        public boolean isSuccess() {
+            return false;
+        }
+
         @Override
         public String toString() {
             return "DataResult.Error['" + message() + "'" + partialValue.map(value -> ": " + value).orElse("") + "]";
diff --git a/src/main/java/com/mojang/serialization/DynamicOps.java b/src/main/java/com/mojang/serialization/DynamicOps.java
index 951ab9b8..a7bd844a 100644
--- a/src/main/java/com/mojang/serialization/DynamicOps.java
+++ b/src/main/java/com/mojang/serialization/DynamicOps.java
@@ -151,7 +151,7 @@ default DataResult<Consumer<Consumer<T>>> getList(final T input) {
     default DataResult<ByteBuffer> getByteBuffer(final T input) {
         return getStream(input).flatMap(stream -> {
             final List<T> list = stream.collect(Collectors.toList());
-            if (list.stream().allMatch(element -> getNumberValue(element).result().isPresent())) {
+            if (list.stream().allMatch(element -> getNumberValue(element).isSuccess())) {
                 final ByteBuffer buffer = ByteBuffer.wrap(new byte[list.size()]);
                 for (int i = 0; i < list.size(); i++) {
                     buffer.put(i, getNumberValue(list.get(i)).result().get().byteValue());
@@ -168,9 +168,9 @@ default T createByteList(final ByteBuffer input) {
 
     default DataResult<IntStream> getIntStream(final T input) {
         return getStream(input).flatMap(stream -> {
-            final List<T> list = stream.collect(Collectors.toList());
-            if (list.stream().allMatch(element -> getNumberValue(element).result().isPresent())) {
-                return DataResult.success(list.stream().mapToInt(element -> getNumberValue(element).result().get().intValue()));
+            final List<T> list = stream.toList();
+            if (list.stream().allMatch(element -> getNumberValue(element).isSuccess())) {
+                return DataResult.success(list.stream().mapToInt(element -> getNumberValue(element).getOrThrow().intValue()));
             }
             return DataResult.error(() -> "Some elements are not ints: " + input);
         });
@@ -182,9 +182,9 @@ default T createIntList(final IntStream input) {
 
     default DataResult<LongStream> getLongStream(final T input) {
         return getStream(input).flatMap(stream -> {
-            final List<T> list = stream.collect(Collectors.toList());
-            if (list.stream().allMatch(element -> getNumberValue(element).result().isPresent())) {
-                return DataResult.success(list.stream().mapToLong(element -> getNumberValue(element).result().get().longValue()));
+            final List<T> list = stream.toList();
+            if (list.stream().allMatch(element -> getNumberValue(element).isSuccess())) {
+                return DataResult.success(list.stream().mapToLong(element -> getNumberValue(element).getOrThrow().longValue()));
             }
             return DataResult.error(() -> "Some elements are not longs: " + input);
         });
diff --git a/src/main/java/com/mojang/serialization/codecs/BaseMapCodec.java b/src/main/java/com/mojang/serialization/codecs/BaseMapCodec.java
index 3050ee94..89835b64 100644
--- a/src/main/java/com/mojang/serialization/codecs/BaseMapCodec.java
+++ b/src/main/java/com/mojang/serialization/codecs/BaseMapCodec.java
@@ -42,7 +42,7 @@ default <T> DataResult<Map<K, V>> decode(final DynamicOps<T> ops, final MapLike<
                         return r.apply2stable((u, p) -> u, DataResult.error(() -> "Duplicate entry for key: '" + entry.get().getFirst() + "'"));
                     }
                 }
-                if (entryResult.error().isPresent()) {
+                if (entryResult.isError()) {
                     failed.add(pair);
                 }
 
diff --git a/src/main/java/com/mojang/serialization/codecs/DispatchedMapCodec.java b/src/main/java/com/mojang/serialization/codecs/DispatchedMapCodec.java
index 4102e7a6..5ea28c74 100644
--- a/src/main/java/com/mojang/serialization/codecs/DispatchedMapCodec.java
+++ b/src/main/java/com/mojang/serialization/codecs/DispatchedMapCodec.java
@@ -68,7 +68,7 @@ private <T> DataResult<Unit> parseEntry(final DataResult<Unit> result, final Dyn
                 return result.apply2stable((u, p) -> u, DataResult.error(() -> "Duplicate entry for key: '" + key + "'"));
             }
         }
-        if (entryResult.error().isPresent()) {
+        if (entryResult.isError()) {
             failed.add(input);
         }
 
diff --git a/src/main/java/com/mojang/serialization/codecs/EitherCodec.java b/src/main/java/com/mojang/serialization/codecs/EitherCodec.java
index da6f7e88..1ad0b6b2 100644
--- a/src/main/java/com/mojang/serialization/codecs/EitherCodec.java
+++ b/src/main/java/com/mojang/serialization/codecs/EitherCodec.java
@@ -12,11 +12,11 @@ public record EitherCodec<F, S>(Codec<F> first, Codec<S> second) implements Code
     @Override
     public <T> DataResult<Pair<Either<F, S>, T>> decode(final DynamicOps<T> ops, final T input) {
         final DataResult<Pair<Either<F, S>, T>> firstRead = first.decode(ops, input).map(vo -> vo.mapFirst(Either::left));
-        if (firstRead.error().isEmpty()) {
+        if (firstRead.isSuccess()) {
             return firstRead;
         }
         final DataResult<Pair<Either<F, S>, T>> secondRead = second.decode(ops, input).map(vo -> vo.mapFirst(Either::right));
-        if (secondRead.error().isEmpty()) {
+        if (secondRead.isSuccess()) {
             return secondRead;
         }
         return firstRead.apply2((f, s) -> s, secondRead);
diff --git a/src/main/java/com/mojang/serialization/codecs/EitherMapCodec.java b/src/main/java/com/mojang/serialization/codecs/EitherMapCodec.java
index d3c9067d..b7ff61cb 100644
--- a/src/main/java/com/mojang/serialization/codecs/EitherMapCodec.java
+++ b/src/main/java/com/mojang/serialization/codecs/EitherMapCodec.java
@@ -25,11 +25,11 @@ public EitherMapCodec(final MapCodec<F> first, final MapCodec<S> second) {
     @Override
     public <T> DataResult<Either<F, S>> decode(final DynamicOps<T> ops, final MapLike<T> input) {
         final DataResult<Either<F, S>> firstRead = first.decode(ops, input).map(Either::left);
-        if (firstRead.error().isEmpty()) {
+        if (firstRead.isSuccess()) {
             return firstRead;
         }
         final DataResult<Either<F, S>> secondRead = second.decode(ops, input).map(Either::right);
-        if (secondRead.error().isEmpty()) {
+        if (secondRead.isSuccess()) {
             return secondRead;
         }
         return firstRead.apply2((f, s) -> s, secondRead);
diff --git a/src/main/java/com/mojang/serialization/codecs/KeyDispatchCodec.java b/src/main/java/com/mojang/serialization/codecs/KeyDispatchCodec.java
index ba98e7c8..5da4edc7 100644
--- a/src/main/java/com/mojang/serialization/codecs/KeyDispatchCodec.java
+++ b/src/main/java/com/mojang/serialization/codecs/KeyDispatchCodec.java
@@ -60,7 +60,7 @@ public <T> DataResult<V> decode(final DynamicOps<T> ops, final MapLike<T> input)
     public <T> RecordBuilder<T> encode(final V input, final DynamicOps<T> ops, final RecordBuilder<T> prefix) {
         final DataResult<? extends MapEncoder<V>> encoderResult = encoder.apply(input);
         final RecordBuilder<T> builder = prefix.withErrorsFrom(encoderResult);
-        if (encoderResult.result().isEmpty()) {
+        if (encoderResult.isError()) {
             return builder;
         }
 
diff --git a/src/main/java/com/mojang/serialization/codecs/OptionalFieldCodec.java b/src/main/java/com/mojang/serialization/codecs/OptionalFieldCodec.java
index d18ec781..27451152 100644
--- a/src/main/java/com/mojang/serialization/codecs/OptionalFieldCodec.java
+++ b/src/main/java/com/mojang/serialization/codecs/OptionalFieldCodec.java
@@ -32,7 +32,7 @@ public <T> DataResult<Optional<A>> decode(final DynamicOps<T> ops, final MapLike
             return DataResult.success(Optional.empty());
         }
         final DataResult<A> parsed = elementCodec.parse(ops, value);
-        if (parsed.result().isEmpty() && lenient) {
+        if (parsed.isError() && lenient) {
             return DataResult.success(Optional.empty());
         }
         return parsed.map(Optional::of).setPartial(parsed.resultOrPartial());
diff --git a/src/test/java/com/mojang/serialization/CodecTests.java b/src/test/java/com/mojang/serialization/CodecTests.java
index 200b42f1..15ac630d 100644
--- a/src/test/java/com/mojang/serialization/CodecTests.java
+++ b/src/test/java/com/mojang/serialization/CodecTests.java
@@ -34,7 +34,7 @@ private static <T> T fromJavaOrPartial(final Codec<T> codec, final Object value)
 
     private static void assertFromJavaFails(final Codec<?> codec, final Object value) {
         final DataResult<?> result = codec.parse(JavaOps.INSTANCE, value);
-        assertTrue("Expected data result error, but got: " + result.result(), result.result().isEmpty());
+        assertTrue("Expected data result error, but got: " + result.result(), result.isError());
     }
 
     private static void assertFromJavaFailsPartial(final Codec<?> codec, final Object value) {
@@ -44,7 +44,7 @@ private static void assertFromJavaFailsPartial(final Codec<?> codec, final Objec
 
     private static <T> void assertToJavaFails(final Codec<T> codec, final T value) {
         final DataResult<Object> result = codec.encodeStart(JavaOps.INSTANCE, value);
-        assertTrue("Expected data result error, but got: " + result.result(), result.result().isEmpty());
+        assertTrue("Expected data result error, but got: " + result.result(), result.isError());
     }
 
     private static <T> void assertRoundTrip(final Codec<T> codec, final T value, final Object java) {