msync: Database Migration Synchronization Tool

A lightweight CLI tool that detects out-of-sync databases and prevents commits when developers forget to run migrations. msync ensures that local development databases stay synchronized with reference environments, eliminating "it works on my machine but not work on server :)" issues.

Problem

Backend teams waste 2-3 hours per week on database synchronization issues:

• New columns exist in code but not in local database
• New hires spend hours debugging missing tables
• CI failures due to schema drift
• Onboarding takes days instead of hours

Solution

msync automates database migration synchronization by:

1. Detecting your current migration version
2. Comparing against production or team reference databases
3. Blocking commits when out of sync
4. Providing clear commands to resolve drift

Features

Feature
CLI status check
Schema diff visualization
Migration apply (up)
Pre-commit hook
CI verification mode
Multiple adapter support

Supported Frameworks

msync supports major migration frameworks across multiple languages:

Framework	Language
Alembic (SQLAlchemy)	Python
Rails ActiveRecord	Ruby
Django Migrations	Python
Prisma Migrate	TypeScript

Installation

Linux / macOS / WSL

git clone https://github.com/Melphins/msync.git
cd msync
./install.sh

Windows

PowerShell

git clone https://github.com/Melphins/msync.git
cd msync
.\install.ps1

Quick Start

# In your project directory, run the init wizard
msync init

# Follow the interactive prompts to configure your adapters and targets

# Check sync status
msync status --target production

# Apply pending migrations
msync up --target production

# See what would change
msync diff --target production

# CI/CD verification (exits with code based on status)
msync verify --target production

Configuration

The msync init command provides an interactive wizard to generate your .msync.yml configuration file. The configuration defines:

• Local database adapter and connection
• Target environment(s) to sync against
• Thresholds for warnings and errors
• Pre-commit hook settings

Pre-commit Hook

Install the pre-commit hook to automatically verify database sync before each commit:

msync install-hook

The hook will check your database against the target and prevent commits when out of sync. Configure hook behavior in .msync.yml. Use git commit --no-verify to bypass the check when necessary.

Platform Support

msync is available on all major platforms:

Platform
Linux
macOS
Windows
WSL

Technical Details

msync follows a clean architecture with adapter pattern implementation:

• Adapter Registry: Factory-based adapter loading for extensibility
• Configuration System: YAML-based with environment variable substitution
• Transaction Safety: Each migration runs in its own transaction
• Dry-run Support: Preview changes before applying
• CI/CD Ready: Exit codes and JSON output for automation

License

MIT License - see LICENSE file for details.