MassCode
A free and open source code snippet manager for developers
Install / Use
/learn @massCodeIO/MassCodeREADME
Support
massCode is an open-source project and completely free to use.
Maintaining and adding new features requires significant time and effort. If you find massCode useful, consider supporting its development. Your contribution helps keep the project alive and moving forward.
You can support massCode through the following channels:
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Features
Organization
Organize your snippets with multi-level folders and tags. Each snippet can contain multiple fragments (tabs), giving you fine-grained control over structure and grouping.
Editor
Built on CodeMirror with .tmLanguage grammars for syntax highlighting.
- Supports over 600 grammars, with 160+ available out of the box.
- Integrated Prettier for clean, consistent code formatting.
Real-time HTML & CSS Preview
Write and instantly preview HTML and CSS snippets. Perfect for prototyping, testing ideas, or quick visual checks.
Markdown
Full Markdown support with syntax highlighting, tables, lists, and more.
- Integrated Mermaid for dynamic diagrams and charts.
Presentation Mode
Turn a sequence of snippets into a presentation. Useful for classrooms, team meetings, conference talks, or simply walking through your own notes.
Mindmap
Generate mind maps from Markdown. Fast, intuitive, and ideal for structuring and visualizing ideas.
JSON Visualizer
Visualize and explore your JSON data with an interactive graph view. Perfect for quickly inspecting complex responses, APIs, or configuration files.
Math Notebook
A calculator notepad inspired by Numi. Write expressions in natural language and get instant results on each line. Supports arithmetic, percentages, unit conversions, 28 currencies with live rates, date & time operations, variables, and more.
Beautiful Screenshots
Export snippets as polished images with customizable themes and backgrounds.
Developer Tools
Handy built-in utilities for everyday dev tasks:
- Text Tools: Case Converter, Slug Generator, URL Parser
- Crypto & Security: Hash/HMAC, Password Generator, UUID
- Encoders/Decoders: URL, Base64, JSON ⇄ TOML/XML/YAML, Text ⇄ ASCII/Binary/Unicode, Color Converter
Custom Themes
Fully customize the UI and editor syntax highlighting with JSON theme files stored in ~/.massCode/themes/. Supports light and dark types with live reload.
Integrations
Extend your workflow with:
- VS Code Extension: zen mode snippet search, instant insertion, and save selected code as snippets.
- Raycast Extension: quick snippet access directly from Raycast.
Storage
massCode supports two storage engines — you can switch between them in Settings → Storage.
Markdown Vault
The default storage engine. Snippets are stored as plain .md files on disk with frontmatter metadata. The vault structure mirrors your folder hierarchy.
- Git-friendly — track changes, sync via GitHub or any Git remote.
- Cloud sync — works with iCloud, Dropbox, Syncthing, or any file sync service.
- Live sync — massCode watches the vault directory and picks up external changes in real time.
SQLite (Legacy)
All data is stored in a single SQLite database file. SQLite engine is deprecated and will be removed in future versions. Please migrate to Markdown Vault.
Overview
massCode was created as a personal learning project and evolved into an open-source tool. The goal: combine the best features of snippet managers (free and paid) into one flexible, developer-friendly application.
Build Locally
Prerequisites
- Node.js (>=20.16.0)
- pnpm (>= 9.0.0)
Install Dependencies
pnpm install
Build
To build for current platform:
pnpm build
To build for a specific platform:
pnpm build:mac # macOS
pnpm build:win # Windows
pnpm build:linux # Linux
Development
To run in development mode:
pnpm dev
This will start the application with hot reloading.
Troubleshooting
macOS
If you encounter the error message "massCode" is damaged and can't be opened. You should move it to the Trash while installing software on macOS, it may be due to security settings r
