FileShift

A powerful native macOS application for converting, splitting, and merging JSON, JSONL, and CSV files.

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Quick Start

Download: FileShift for Apple Silicon (M1/M2/M3/M4)

First Launch: Right-click the app and select "Open" to bypass the security warning (see Installation for details)

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Features

Convert Tab

• Batch Processing: Convert multiple JSON files to CSV at once
• Smart Schema Analysis: Automatically analyzes and compares schemas across files
• Multiple Merge Strategies:
  • Smart Auto: Fields present in 70%+ of files
  • All Available: Union of all fields across files
  • Common Only: Fields present in ALL files
  • Most Complete File: Use the file with most fields as template
  • Keep Separate: Individual CSV files with their own schemas
• Nested Field Support: Handles complex nested JSON structures

Split Tab

• Split by Number of Files: Divide a file into N equal parts
• Split by Rows: Create files with a specific number of records each
• Split by Size: Create files of approximately N kilobytes each
• Format Flexibility: Input can be JSON, JSONL, or CSV; output format is selectable

Merge Tab

• Combine Multiple Files: Merge any number of files into one
• Mixed Format Support: Merge JSON, JSONL, and CSV files together
• Schema Strategies:
  • Union: Include all fields from all files
  • Intersection: Only include fields common to all files
  • First File: Use the schema from the first file
• Output Format Selection: Choose JSON, JSONL, or CSV output

General

• Native macOS Interface: Built with PyQt6 for a smooth, native experience
• Real-time Progress: Track operations with progress bars and status logs
• Memory Efficient: Streaming processing for large files

Download

Mac Type	Download Link
Apple Silicon (M1/M2/M3/M4)	Download DMG

All Releases: View all versions on the Releases page

Installation

1. Download the DMG file
2. Double-click the DMG to mount it
3. Drag "FileShift" to your Applications folder
4. First time running: The app will show a security warning because it's not signed with an Apple Developer certificate ($99/year). See below for how to bypass this.

Opening an Unsigned App on macOS

macOS Gatekeeper blocks apps without Apple Developer certificates. Choose one of the methods below:

Method 1: Right-Click → Open (Simplest)

1. Right-click (or Control-click) on FileShift.app in Finder
2. Select Open from the context menu
3. Click Open in the dialog that appears

This presents a different dialog that allows you to open the app directly.

Method 2: System Settings (If Method 1 Doesn't Work)

1. Try to open the app normally (double-click) — You'll see a warning. Click Done (not "Move to Trash").

2. Open System Settings → Privacy & Security

3. Scroll down to the Security section. You'll see:

   "FileShift.app" was blocked from use because it is not from an identified developer.

   Click Open Anyway

4. Enter your password if prompted, then click Open Anyway again in the confirmation dialog.

Method 3: Terminal Command (Most Reliable)

If the above methods don't work, remove the quarantine flag using Terminal:

xattr -d com.apple.quarantine /Applications/FileShift.app

Then open the app normally.

Method 4: Run from Source (No Restrictions)

Running from source bypasses Gatekeeper entirely:

git clone https://github.com/simplifi/FileShift.git
cd FileShift
python -m venv .venv
source .venv/bin/activate
pip install PyQt6
python -m src

After completing any method once, the app will open normally without warnings.

Usage

Converting Files

1. Go to the Convert tab
2. Click "Browse for JSON Files" to select one or more JSON files
3. The app automatically analyzes the structure of your files
4. Select a merge strategy for handling different schemas
5. Click "Convert All Files" and choose an output directory

Splitting Files

1. Go to the Split tab
2. Select a single input file (JSON, JSONL, or CSV)
3. Choose a split mode:
   • By number of files: Split into N equal parts
   • By rows per file: Each output file has N records
   • By file size: Each output file is approximately N KB
4. Select output format and directory
5. Click "Split File"

Merging Files

1. Go to the Merge tab
2. Select multiple input files (can be mixed formats)
3. Choose a schema strategy:
   • Union: All fields from all files
   • Intersection: Only common fields
   • First file: Use first file's schema
4. Select output format and file path
5. Click "Merge Files"

Building from Source

Requirements

• macOS 11 or later
• Python 3.9 or later
• PyQt6

Quick Build

# Clone the repository
git clone https://github.com/simplifi/FileShift.git
cd FileShift

# Create virtual environment
python -m venv .venv
source .venv/bin/activate

# Install dependencies
pip install PyQt6 pyinstaller

# Build the app
pyinstaller --clean fileshift.spec

The built application will be in dist/FileShift.app

Development

Setting up the development environment

# Create virtual environment
uv venv
source .venv/bin/activate

# Install dependencies
uv pip install -e ".[dev]"

# Run the application
python -m src

# Run tests
pytest

Project Structure

FileShift/
├── src/
│   ├── gui.py                      # Main GUI application
│   ├── main.py                     # Entry point
│   └── converters/                 # Core conversion library
│       ├── base.py                 # Base classes and types
│       ├── handlers.py             # Format handlers (JSON, JSONL, CSV)
│       └── operations.py           # Split and merge operations
├── tests/                          # Test suite
├── packaging/
│   └── fileshift.spec              # PyInstaller build spec
└── pyproject.toml                  # Project configuration

Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Built with PyQt6
• Packaged with PyInstaller

Support

For issues, questions, or contributions, please visit the GitHub repository.