___  ___        ___  ________  ________  ___       ___  _________   _______     
|\  \|\  \      |\  \|\   ____\|\   __  \|\  \     |\  \|\___   ___\/  ___  \    
\ \  \\\  \     \ \  \ \  \___|\ \  \|\  \ \  \    \ \  \|___ \  \_/__/|_/  /|   
 \ \   __  \  __ \ \  \ \_____  \ \   ____\ \  \    \ \  \   \ \  \|__|//  / /   
  \ \  \ \  \|\  \\_\  \|____|\  \ \  \___|\ \  \____\ \  \   \ \  \   /  /_/__  
   \ \__\ \__\ \________\____\_\  \ \__\    \ \_______\ \__\   \ \__\ |\________\
    \|__|\|__|\|________|\_________\|__|     \|_______|\|__|    \|__|  \|_______|
                        \|_________|

A spiritual successor to HJSplit
Fast, cross-platform file splitting and joining tool

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Overview

hjsplit2 is a modern, open-source replacement for the classic HJSplit utility. It lets you split large files into smaller chunks and rejoin them later — perfect for transferring big files over email, USB drives, or cloud storage with size limits.

Built with Go and the Fyne GUI toolkit, featuring a dark navy/synthwave theme inspired by classic terminal aesthetics.

Features

• ✂️ Split — divide any file into custom-sized parts (.001, .002, ...)
• 🔗 Join — merge split files back to the original
• 🔀 Custom Join — join multiple files in any order via drag-and-drop list
• 🖱️ Drag & Drop — drop files directly onto the window
• 🎨 Synthwave Theme — dark navy, hot pink, and teal aesthetics
• 🖥️ Console Log — real-time operation log with terminal-style output
• 📦 Portable — single executable, no installation required
• 🌍 Cross-platform — Windows, Linux, macOS

Downloads

Pre-built binaries for Windows (32-bit and 64-bit) and Linux are available in the dist directory after building.

Platform	File
Windows 64-bit	hjsplit2-v*-windows-amd64.exe
Windows 32-bit	hjsplit2-v*-windows-386.exe
Linux 64-bit	hjsplit2-v*-linux-amd64

Building

Prerequisites

• Go 1.21 or later
• MinGW-w64 (Windows, for CGO/GLFW)
• UPX (optional, for smaller binaries)

Quick build (native)

go build -ldflags="-s -w -H windowsgui" -o hjsplit2.exe .

Using build scripts

# Windows — build all platforms
.\build.ps1 all

# Build only for current platform
.\build.ps1 native

# Build specific targets
.\build.ps1 win64
.\build.ps1 win32         # requires MINGW32_PATH in build.conf
.\build.ps1 linux          # requires WSL with Go installed

# Linux / WSL
./build.sh all
./build.sh native
./build.sh win64           # requires MinGW cross-compiler

Cross-compilation notes

The build scripts automatically detect available toolchains:

• win64: uses system MinGW-w64 (64-bit)
• win32: configure MINGW32_PATH or CC_386 in build.conf
• Linux (from Windows): builds via WSL if Go is installed in WSL
• Linux (native): builds directly

Configure paths in build.conf (copy from build.conf.example):

MINGW32_PATH=C:/Apps/mingw32
WSL_DISTRO=Ubuntu
USE_UPX=true

Usage

Split

1. Go to the Split tab
2. Drag a file onto the window (or click to browse)
3. Set the chunk size (KB, MB, or GB)
4. Click Split

Join (auto-detect)

1. Go to the Join tab
2. Drag a .001 file onto the window
3. Click Join — automatically finds and merges .001, .002, ...

Custom Join (any order)

1. Go to the Join tab
2. Click Custom Join...
3. Add files with Add files..., reorder with ↑ / ↓
4. Set the output path and click START JOIN

Output files from Split follow the .001, .002, ... naming convention, compatible with the original HJSplit format.

Tech Stack

• Language: Go
• GUI: Fyne v2
• Theme: Custom Synthwave (Python‑inspired palette)
• Windowing: GLFW via Fyne
• Original concept: HJSplit

License

This project is licensed under the GNU General Public License v3.0 — see the LICENSE file for details.

Attribution

Split icon by Icons8