zstdify-cli

Command-line tool for compressing and decompressing files with zstd. Built on the zstdify package (pure TypeScript, no native dependencies).

Features

• Pure JS/TS zstd CLI: No native addon dependency, portable across Node.js environments.
• Compression + extraction workflows: Simple file-to-file commands with level/checksum controls.
• Interop-focused: Files produced by zstdify are decoded by the official zstd CLI, and zstd output is decoded by zstdify.
• Robust command UX: Clear subcommands, aliases, and actionable error messages.
• Optional dictionary support: Train dictionaries from samples and use them with compress/extract when needed.

Installation

pnpm add -g zstdify-cli

Commands

| Command | Description | | ------- | ----------- | | zstdify compress <input> <output> | Compress a file with zstd | | zstdify extract <input> <output> | Decompress a zstd-compressed file | | zstdify dict train <output> --input <path>... | Train a dictionary from sample files/directories |

Aliases: compress / c, extract / x.

Options (compress)

• --level, -l — Compression level (0=raw, 1+=RLE, 2+=compressed blocks)
• --checksum — Add content checksum to the frame
• --dict — Dictionary file path to use for compression
• --dictID — Dictionary ID to store in the frame header
• --noDictId — Do not write dictID in frame header

Options (extract)

• --dict — Dictionary file path for dictionary-compressed input
• --dictID — Expected dictionary ID for validation

Options (dict train)

• --recursive — Recursively collect files from input directories
• --maxSamples — Maximum number of sample files to load
• --algorithm — fastcover, cover, or legacy
• --maxdict — Maximum dictionary size in bytes
• --dictID — Optional dictionary ID metadata setting
• Advanced tuning knobs: --k, --d, --steps, --split, --f, --accel, --selectivity, --shrink

Examples

zstdify compress input.txt output.zst
zstdify compress input.txt output.zst --level 2
zstdify extract output.zst restored.txt
zstdify dict train my.dict --input samples/ --recursive --maxdict 2048
zstdify compress input.txt output.zst --dict my.dict --dictID 42
zstdify extract output.zst restored.txt --dict my.dict --dictID 42

How we validate

CLI behavior is covered by automated tests (pnpm vitest, including packages/cli-tests):

• CLI round-trip: zstdify compress -> zstdify extract restores original file bytes.
• Core flags and aliases: Compression levels, checksums, and command aliases are exercised.
• Differential interop with official zstd CLI:
  • zstd output is extracted by zstdify-cli.
  • zstdify-cli output is decompressed by zstd.
  • These checks run across standard (non-dictionary) workflows.
• Dictionary interop coverage:
  • zstd -D dict compressed streams are extracted by zstdify-cli --dict.
  • zstdify-cli --dict compressed streams are decompressed by zstd -D dict.
  • Coverage includes both zstd-trained and zstdify-trained dictionaries.
• Error paths: Missing files and invalid inputs produce non-zero exits and actionable messages.

Acknowledgements

This project is made possible by the original zstd project by Meta and its contributors. The monorepo, project, and CLI structure were bootstrapped from hdrify, which made this project much easier to build.

License

MIT

Author

Ben Houston, Sponsored by Land of Assets