Aqueous archiver 2026-11-01

Download and execute aqr-20261101-win-install.exe if you have no other reason.
Download aqr-20261101-win7.exe if you use Windows 8 or earlier.

Newly Supported Formats

• ALZip archive (.alz)
• ALZip EGG archive (.egg)
• Apple ProRes in QuickTime/MXF (.mov, .mxf)
• ELF executables and objects
• JSON Lines (.jsonl) and JSON arrays written one value per line
• LHA archive (.lzh, .lha) --- -lh4- to -lh7- only
• Matroska/WebM (.mkv, .webm) --- intended for videos of a still picture
• RAR archive (.rar): RAR5 and RAR 3.x/4.x (RAR 2.9 LZ and PPMd, standard filters) --- PPMd streams only in -9; volumes and SFX are not supported yet
• Aqueous archive nested in input (.aqr) --- module and resource blocks are shared with the outer archive

Changes to Existing Formats

• IMA ADPCM
  • WAV files are now supported
• Vorbis
  • Ogg files are now supported
• Text
  • Text with up to 1 in 1000 non-text bytes is now taken as text (e.g. a trailing Ctrl-Z)
• tar (and ar, cpio, asar) as a single input
  • Members and blocks are now made in parallel

User-facing Changes

• aqr -d and aqr -t support other archives: ZIP, 7z, tar (alone or with gzip/bzip2/xz/LZMA/zstd), RAR, ALZ and EGG, plus single compressed files (.gz, .xz, …)
  • Other archives are extracted as they are into the current directory (or -o), like tar and 7z x
  • Encrypted ZIP entries and 7z folders/headers are decrypted
• aqr -d ARCHIVE PATH... extracts or tests only the given paths and decodes only what they need
  • PATH --rename TO changes the target path
  • The prior behavior is now available through aqr -d --each ARCHIVE ARCHIVE...
• --auto-dir places the output by what the archive holds, as GUI extractors do
• -P encrypts archives and encrypted archives ask for a passphrase
• -h/--help and -V/--version were added
• GUI support via the --ipc protocol
  • Windows: Explorer verbs and a progress window (aqr-win), an installer (aqr-win-install), a passphrase dialog and the droplet icon
  • macOS: Aqueous.app adds Finder services, opens .aqr files and shows progress in Finder, with a passphrase dialog (no notarization yet)
• Linux x86_64/aarch64 binaries are built with each release, and a Nix flake was added (nix build)

Specification Changes

• ModuleBytes (02) and ResourceBytes (03) opcodes, so nested archives can share blocks

Compression Optimizations

• Incompressible streams are now tried whole at zstd level 1

Performance Optimizations

• Opening an archive for a few paths is much faster
  • Formula blocks are lazily decoded
  • Metadata is read via streaming
  • Zstd context is now reused within each thread
• LZMA/LZMA2 decoding during extraction is 1.8× as fast
• 7z folders are written out as they are decoded
• Compression uses less memory
  • Formula is held in the store rather than in memory
  • Concatenations are checked part by part
• Faster coding of JPEG and GPU textures
• Spill files are named after the output, and on Windows they are hidden and excluded from indexing

Bug Fixes

• Windows: extraction can no longer write outside the target directory, whether through lone surrogates, fork names or link targets
• Names are now compared as the target file system would (case, Unicode normalization, FAT short names; on macOS, Windows and Linux)
  • Entries the file system would take as one are reported and skipped, instead of failing or overwriting each other with -f
  • Links can no longer reach outside the target directory through names differing only in case or normalization
  • A mode or times are no longer applied through a link made later over the same path
• Fix a panic ("output taken before it is") on archives with nested shared applications, e.g. an EGG archive holding a PDF at -9
• aqr-bz2: a memory bound could be exceeded on some blocks

Aqueous archiver 2026-10-31

Download and execute aqr-20261031a-win-install.exe if you have no other reason. (It is based on 5393aa3, unlike others.)
Download aqr-20261031-win7.exe if you use Windows 8 or earlier.

Newly Supported Formats

• 7-Zip archive (.7z) and almost all built-in non-codec filters --- intended only for deduplication
• Apple LZFSE/LZVN (Assets.car) --- only in -9
• BZip2 (.bz2)
• Clip Studio Paint (.clip)
• Comma, Tab, Semicolon, Pipe and Unicode-separated values (.csv, .tsv, .usv)
• DICOM (.dcm)
• Electron ASAR (.asar)
• FITS (.fits)
• FMOD FSB5 sound bank (.fsb)
• GIF (.gif)
• GNU gettext message (.mo)
• HDF5 (.hdf5)
• IMA ADPCM --- no file support yet
• ISO 9660/UDF image file (.iso)
• LZMA2 and XZ (.xz)
• LZX --- CAB/CHM support only in -9
• MS Cabinet (.cab)
• MS Compiled HTML Help (.chm) --- only in -9
• PPMd var. J (.pmd) --- no decompression, deduplication only
• Uncompressed TIFF (.tif)
• Vorbis --- no Ogg support yet
• WaveFront OBJ (.obj)
• WebAssembly module (.wasm)
• Windows Imaging Format (.wim)

Changes to Existing Formats

• Overall

  • Optimized for module sizes and especially memory footprints
  • Estimated memory usage calculation for all modules
  • Progress meter support

• DEFLATE

  • Dedicated code for zlib -1..3 reproduction

• git repository

  • Share the DEFLATE backend with other files
  • Automatic derivation of .idx and .rev files

• LZMA

  • Compression is now partly multi-threaded

• Mach-O

  • Explicit packing of symbol tables
  • Dedicated delta coding format support ("remap", both x86-64 and AArch64)

• PE (.exe)

  • Explicit packing of tabular sections

• x86-64

  • Greatly reduced the number of input streams

• Photoshop (.psd)

  • Fix a shift overflow in WebAssembly module

• Text

  • WRT is now multi-threaded
  • Specific transformation for Korean hangul
  • Very long lines no longer force single-threaded encoding

• ZIP (.zip)

  • Non-transformed slices are now deduplicable

User-facing Changes

• Progress bars and slow files are displayed during compression and decompression
• Per-file logs are off by default (-v)
• Preset dictionaries can be trained within batches (-D)
• Proper metadata recording and restoration, privileged attributes are also handled via -p
• Batch and block sizes are customizable (-B and -b)
• In-process statistics and profiling (--stats, --stats=report.html etc.)

Specification Changes

• Additional keys for forks (or streams), xattrs and platform-specific metadata
• Mandatory declaration of max concurrency (aqr_task_slots custom section)

Compression Optimizations

• Infer tabular layouts and transpose accordingly
• Improve the clustering of batches via content-defined chunking
• Streams are now sliced and compared against each other for similarity

Performance Optimizations

• Compression uses much less memory now
• Compression is now partially streamed
• apply_memory_limit is now correctly declared for all modules
• Inputs are memory mapped, any detected changes are correctly handled
• Big buffers are now put in spill files
• Large streams are divided in 128 MiB blocks
• Consecutive batches can be pipelined
• Increase the number of ZStandard compression threads
• Process oversized batches and costly files first
• Task memories are now copy-on-write in Windows
• Format-based weighting for compression

Bug Fixes

• Fix a quadratic growth of Swap opcodes with many shared output streams
• Eliminate unused block references in formula blocks
• Treat .log as a text file
• Standalone archive is analyzed according to the input file name
• -T 1 no longer causes occasional hang
• Graceful degradation of sandbox in Windows 8 or earlier