pak-delta

Archive-Aware Content-Defined Delta Compression Engine

Eliminating the DEFLATE entropy cascade in game packfiles (Unreal .pak, Unity .assetbundle, Android .apk, standard .zip).

runtime:0 dependencies
tests:140 passing (100%)
memory:< 64 MB heap
determinism:100% SHA-256 parity
standards:Web Crypto + Streams
license:MIT
Test Configuration ready
FastCDC Pareto Sizing: 2 KB Min / 4 KB Avg / 16 KB Max
Opcode Stream: uLEB128 Packed (80% metadata savings)
Pipeline Metrics 0.00 ms
Baseline Container
--
awaiting execution
Target Container
--
awaiting execution
Generated Delta (PAKD)
--
awaiting execution
Bandwidth Savings
--
vs full re-download
COPY: 0 PATCH (Span): 0 INSERT: 0
STATUS
Target Archive SHA-256: --
Reconstituted Archive SHA-256: --
Execution Trace Log
Container Slices and Recipe Opcodes Inspector
Entry Name Method Uncompressed Compressed CRC32 Alignment Opcode Count Opcodes Breakdown
No active recipe. Run the pipeline above to inspect manifest opcodes.

Technical Specifications and Scientific Documentation

ARCHITECTURE.md

High-level dataflow, streaming bounded memory allocation model, and engine state machine.

ARCHIVE_FORMATS_AND_SLICING.md

Container layout (ZIP, PAK, APK), back-to-front slicing, and DMA sector alignment.

CONTENT_DEFINED_CHUNKING.md

FastCDC gear hash table, Pareto chunk sizing (4 KB - 8 KB), and dual-threshold masks.

DELTA_RECIPE_SPECIFICATION.md

PAKD binary container layout, uLEB128 opcode stream, and sub-chunk span delta encoding.

DETERMINISTIC_REPACK.md

Dual-mode client reconstitution, IEEE 802.3 CRC32, and atomic file replacement.

TESTING_STRATEGY.md

Five-layer testing pyramid, procedural synthetic fixtures, and chaos failure matrix.

EMPIRICAL_STUDY_AND_BENCHMARKS.md

Comprehensive 13-experiment scientific validation report and empirical measurements.