ImmutableList<ImplementationSnapshot> currentAdditionalImplementations = Cast.uncheckedNonnullCast(thisExecution.getAdditionalImplementations());
        ChangeContainer implementationChanges = new ImplementationChanges(
            previousImplementation, lastExecution.getAdditionalImplementations(),
            currentImplementation, currentAdditionalImplementations,
            executable);

        ImplementationSnapshot implementation = implementationsBuilder.getImplementation();
        ImmutableList<ImplementationSnapshot> additionalImplementations = implementationsBuilder.getAdditionalImplementations();

        if (LOGGER.isDebugEnabled()) {
            LOGGER.debug("Implementation for {}: {}", work.getDisplayName(), implementation);

            return beforeExecutionState.getImplementation();
        }

        @Override
        public ImmutableList<ImplementationSnapshot> getAdditionalImplementations() {
            return beforeExecutionState.getAdditionalImplementations();
        }

        @Override
        public ImmutableSortedMap<String, ValueSnapshot> getInputProperties() {

     */
    ImplementationSnapshot getImplementation();

    /**
     * Used only for tasks to return all the task actions.
     */
    ImmutableList<ImplementationSnapshot> getAdditionalImplementations();

    /**
     * The non-file inputs.
     */
    ImmutableSortedMap<String, ValueSnapshot> getInputProperties();

    /**
     * The file inputs.
     */

    }

    @Override
    public ImplementationSnapshot getImplementation() {
        return implementation;
    }

    @Override
    public ImmutableList<ImplementationSnapshot> getAdditionalImplementations() {
        return additionalImplementations;
    }

    @Override
    public ImmutableSortedMap<String, ValueSnapshot> getInputProperties() {
        return inputProperties;
    }

    @Override

            executionState.getOriginMetadata(),
            executionState.getCacheKey(),
            executionState.getImplementation(),
            executionState.getAdditionalImplementations(),
            executionState.getInputProperties(),
            prepareForSerialization(executionState.getInputFileProperties()),
            executionState.getOutputFilesProducedByWork(),

            beforeExecutionState.getImplementation());
        beforeExecutionState.getImplementation().appendToHasher(cacheKeyHasher);

        beforeExecutionState.getAdditionalImplementations().forEach(additionalImplementation -> {
            logger.warn("Appending additional implementation to build cache key: {}",
                additionalImplementation);

            executionState.getOriginMetadata(),
            executionState.getCacheKey(),
            executionState.getImplementation(),
            executionState.getAdditionalImplementations(),
            executionState.getInputProperties(),
            prepareForSerialization(executionState.getInputFileProperties()),
            executionState.getOutputFilesProducedByWork(),

            .orElse(null);
    }

    @Nullable
    public List<byte[]> getActionClassLoaderHashesBytes() {
        return getBeforeExecutionState()
            .map(BeforeExecutionState::getAdditionalImplementations)
            .filter(additionalImplementation -> !additionalImplementation.isEmpty())
            .map(additionalImplementations -> additionalImplementations.stream()

        implementationSnapshotSerializer.write(encoder, execution.getImplementation());
        ImmutableList<ImplementationSnapshot> additionalImplementations = execution.getAdditionalImplementations();
        encoder.writeSmallInt(additionalImplementations.size());
        for (ImplementationSnapshot actionImpl : additionalImplementations) {
            implementationSnapshotSerializer.write(encoder, actionImpl);