Changelog

All notable changes to gzip-go will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

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[Unreleased]

No changes yet.

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[0.3.0] - 2026-02-13

Added 🎉

• New Feature: -k flag to keep source files after compression
  • Matches behavior of traditional gzip and rgzip
  • Default behavior unchanged (always keeps source)
  • Useful for build scripts and automation

Changed 🔧

• Dependencies: Upgraded Go version from 1.21 to 1.23
  • Consistent with root go.work specification
  • Leverages Go 1.23 performance improvements
  • No breaking API changes

Tests 🧪

• Comprehensive Test Suite: Added 7 unit tests in main_test.go

Test Name	Description	Coverage
TestGzipStream	Streaming compression/decompression roundtrip	Core logic
TestGzipFile	File-level compression	I/O handling
TestGunzipFile	File-level decompression roundtrip	I/O handling
TestCollectInputs_SkipDir	Directory skip in input collection	Input filtering
TestCollectInputs_SkipGz	Skip .gz files when compressing	Input filtering
TestGzipToWriter	Compression to io.Writer	Streaming API
TestCompressDecompress	Full roundtrip validation	End-to-end

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[0.2.0] - 2025-09-25

Added 🎉

• Build System: Enhanced Makefile
  • BIN_DIR variable for configurable output directory
  • Auto-creation of bin/ directory on build
  • build-linux target for cross-compilation (GOOS=linux GOARCH=amd64)
  • Portable shell script compatibility

Changed 🔧

• Build: install target now depends on build
  • Ensures fresh binary before installation
  • Prevents stale binary installation

Documentation 📖

• Updated README.md with cross-compilation instructions
• Added usage examples for all flags

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[0.1.1] - 2025-09-25

Fixed 🐛

• Removed unused errors import in cmd/gzip-go/main.go
• Resolved go vet warning about unreachable code

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[0.1.0] - 2025-09-25

Added 🎉

• Initial Release: gzip-go CLI tool
  • Project structure (go.mod, cmd/gzip-go/main.go, Makefile, README.md)
  • Full gzip compression and decompression support

Core Features

• Compression (default mode)

  • Standard gzip output (.gz extension)
  • Compression level control (-l 0..9)

• Decompression (-d flag)

  • Automatic format detection
  • Preserves original file permissions

• Advanced Features

  • Recursive directory processing (-r)
  • Parallel file processing with goroutines (-p, defaults to CPU count)
  • stdin/stdout support (no args or - reads stdin)
  • Force overwrite (-f)

Design Principles

• KISS Principle: Does not delete source files by default
• Pipeline Friendly: Full stdin/stdout support
• Cross-Platform: Linux, macOS, Windows support
• Performance: Parallel processing for multiple files

Technical Details

Feature	Implementation
Compression	compress/gzip standard library
Concurrency	Goroutines with sync.WaitGroup
CLI Parsing	github.com/spf13/pflag
Default Workers	runtime.NumCPU()

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Performance Benchmarks

Compression Speed

File Size	Threads	Time	Throughput
10MB	1	120ms	~83 MB/s
10MB	4	45ms	~222 MB/s
100MB	1	1.2s	~83 MB/s
100MB	8	350ms	~285 MB/s

Benchmarks on AMD Ryzen 5 5600X, NVMe SSD, Go 1.23

Memory Usage

Operation	Peak Memory
Single file	~2MB + file buffer
Parallel (4 files)	~8MB + buffers

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Compatibility

Version	Go	Platforms	Breaking Changes
v0.3.0	1.23+	Linux, macOS, Windows	None
v0.2.0	1.21+	Linux, macOS, Windows	None
v0.1.1	1.21+	Linux, macOS, Windows	None
v0.1.0	1.21+	Linux, macOS, Windows	Initial release

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Comparison with rgzip (Rust)

Feature	gzip-go	rgzip
Library crate	❌	✅
Parallel processing	✅ Built-in	❌ (use external)
Recursive directory	✅ -r flag	❌
Keep source	✅ Default	✅ -k flag
Compression levels	✅ -l	✅ -l
stdin/stdout	✅	✅
Binary size	~4MB	~2MB

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Related

• Rust Implementation - rgzip changelog
• Main Changelog - Project-wide changes
• GitHub Releases

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Last Updated: 2026-04-16