faucet

<p align="center">
  <img src="ui/public/faucet-logo.svg" alt="Faucet logo" height="60">
</p>

<h1 align="center">Faucet: REST API and MCP server for any SQL database</h1>

<h3 align="center">Turn any SQL database into a secure REST API and MCP server.<br>One binary. One command.</h3>

<p align="center">
  <strong>Faucet is an open-source (MIT) single Go binary that turns PostgreSQL, MySQL, MariaDB, SQL Server, Oracle, Snowflake or SQLite into a REST API and an MCP server for AI agents, with role-based access control (RBAC), OpenAPI 3.1 and a built-in admin UI.</strong>
</p>

<p align="center">
  Endpoints, OpenAPI specs and MCP tools are generated from your database schema at runtime. No code generation, no ORM, no boilerplate.
</p>

<p align="center">
  <a href="https://github.com/faucetdb/faucet/releases"><img src="https://img.shields.io/github/v/release/faucetdb/faucet?style=flat-square&color=blue" alt="GitHub Release"></a>
  <a href="https://github.com/faucetdb/faucet/blob/main/LICENSE"><img src="https://img.shields.io/github/license/faucetdb/faucet?style=flat-square" alt="License: MIT"></a>
  <a href="https://hub.docker.com/r/faucetdb/faucet"><img src="https://img.shields.io/docker/pulls/faucetdb/faucet?style=flat-square" alt="Docker Pulls"></a>
  <a href="https://github.com/faucetdb/faucet/actions/workflows/ci.yml"><img src="https://img.shields.io/github/actions/workflow/status/faucetdb/faucet/ci.yml?branch=main&style=flat-square&label=CI" alt="CI Status"></a>
  <a href="https://goreportcard.com/report/github.com/faucetdb/faucet"><img src="https://goreportcard.com/badge/github.com/faucetdb/faucet?style=flat-square" alt="Go Report Card"></a>
</p>

<p align="center">
  <a href="https://faucetdb.ai">Website</a> &middot;
  <a href="https://wiki.faucetdb.ai">Docs</a> &middot;
  <a href="#60-second-quickstart">Getting Started</a> &middot;
  <a href="https://hub.docker.com/r/faucetdb/faucet">Docker</a> &middot;
  <a href="#mcp-server-for-ai-agents">MCP Server</a> &middot;
  <a href="https://github.com/faucetdb/faucet/issues">Issues</a>
</p>

---

## What is Faucet?

Faucet is a **database-to-REST-API gateway** — a lightweight, self-hosted server that connects to your SQL databases, introspects the schema, and generates a full CRUD REST API with authentication, role-based access control (RBAC), and OpenAPI documentation. It also exposes an **MCP server** at `/mcp` so AI agents and AI app builders (Claude, ChatGPT, Cursor, VS Code, Windsurf, Base44, Replit) can query your data through the same roles and API keys.

Think of it as an open-source alternative to [DreamFactory](https://www.dreamfactory.com/), [PostgREST](https://postgrest.org/), or [Hasura](https://hasura.io/), with multi-database support, a built-in admin UI, and native AI agent integration, all in a single binary. See [how it compares](#faucet-vs-postgrest-vs-hasura-vs-dreamfactory-vs-supabase).

<p align="center"><img src="screenshots/admin-databases.webp" alt="Faucet admin UI listing connected PostgreSQL and SQLite databases" width="800"></p>

### Use Cases

- **Instant backend for apps** — Skip writing CRUD APIs by hand. Point Faucet at your database and start building your frontend.
- **AI agent data access** — Give Claude, GPT, or any MCP-compatible agent governed, read/write access to your databases.
- **Internal tools & dashboards** — Generate APIs for internal databases without modifying existing infrastructure.
- **Legacy database modernization** — Put a REST API in front of SQL Server 2012, MySQL 5.7, or PostgreSQL 9.6 without code changes.
- **Multi-database aggregation** — Connect PostgreSQL, MySQL, SQL Server, Oracle, and more to a single Faucet instance and query them all through one API.
- **Rapid prototyping** — Go from empty database to working API in under 60 seconds.

---

## How It Works

```
┌──────────────┐       ┌───────────────────────────────────────┐       ┌──────────────┐
│ PostgreSQL   │       │              F A U C E T              │       │   REST API   │
│ MySQL        │──────▶│                                       │──────▶│   /api/v1/*  │
│ MariaDB      │  SQL  │  ┌─────────┐ ┌──────┐ ┌───────────┐   │       ├──────────────┤
│ SQL Server   │◀──────│  │ Schema  │ │ RBAC │ │  OpenAPI  │   │──────▶│  OpenAPI 3.1 │
│ Oracle       │       │  │ Intro-  │ │ Auth │ │ Generator │   │       │ /openapi.json│
│ Snowflake    │       │  │ spection│ │      │ │           │   │       ├──────────────┤
│ SQLite       │       │  └─────────┘ └──────┘ └───────────┘   │──────▶│  MCP Server  │
└──────────────┘       │                                       │       │  (AI Agents) │
                       │  ┌──────────────────────────────────┐ │       ├──────────────┤
                       │  │   Embedded Admin UI (Preact)     │ │──────▶│   Admin UI   │
                       │  └──────────────────────────────────┘ │       │  :8080/      │
                       └───────────────────────────────────────┘       └──────────────┘
```

**Connect** any SQL database → Faucet **introspects** the schema → Instantly generates **REST endpoints**, **OpenAPI docs**, **MCP tools**, and an **Admin UI** — all secured with API keys, JWT auth, and role-based permissions.

---

## Screenshots

<p align="center">
  <img src="screenshots/admin-add-database.webp" alt="Adding a PostgreSQL database in the Faucet admin UI with host, port, user and password fields" width="800">
  <br><em>Connect a database with host, port, user and password. Faucet tests it before saving and tells you what to fix.</em>
</p>

<p align="center">
  <img src="screenshots/admin-schema.webp" alt="Faucet schema page showing columns, keys and schema drift on a locked table" width="800">
  <br><em>Browse tables, columns, keys and data, and lock your API contract against breaking schema changes.</em>
</p>

<p align="center">
  <img src="screenshots/admin-api-explorer.webp" alt="Faucet API explorer with a filtered query, JSON response and copy-as-curl" width="800">
  <br><em>Build requests with filters and pagination, then copy them as curl, JavaScript or Python.</em>
</p>

<p align="center">
  <img src="screenshots/admin-ai-agents.webp" alt="Faucet AI agents page with ready-made MCP configs for Claude Code, Cursor, VS Code and more" width="800">
  <br><em>Copy-ready MCP setup for Claude Code, Claude Desktop, Cursor, VS Code, Windsurf and ChatGPT.</em>
</p>

See the [Admin UI guide](https://wiki.faucetdb.ai/admin-ui) for a tour of every page.

---

## Key Features

### API Generation
- **Full CRUD REST API** — GET, POST, PUT, PATCH, DELETE with filtering, ordering, and pagination
- **Schema introspection** — Discovers tables, columns, types, and constraints at runtime
- **Schema DDL** — Create, alter, and drop tables via API
- **Stored procedure calls** — Execute stored procedures with typed parameters
- **Human-readable query filters** — `(age > 21) AND (status = 'active')`
- **OpenAPI 3.1 spec** — Auto-generated from live database schema at `/openapi.json`

### Security & Access Control
- **API key authentication** — SHA-256 hashed keys with per-key role assignment
- **JWT authentication** — HMAC-SHA256 signed tokens for admin sessions
- **Role-based access control (RBAC)** — Per-table verb permissions (GET, POST, PUT, PATCH, DELETE)
- **Row-level security filters** — Filter expressions are stored per access rule and returned by the API; applying them to queries is planned and not enforced yet
- **Schema contract locking** — Lock your API contract against silent breaking schema changes with three modes (none, auto, strict), drift detection, and CLI management

### AI Agent Integration (MCP)
- **Built-in MCP server** — 8 tools + 2 resources for Model Context Protocol, served at `/mcp` on the same port as the REST API
- **Works with your AI tools** — Copy-ready configs for Claude Code, Claude Desktop, Cursor, VS Code and Windsurf; ChatGPT via a Custom GPT Action on `/openapi.json`
- **Streamable HTTP + stdio transport** — API-key authenticated over the network, or stdio on your own machine
- **Governed AI queries** — AI agents respect the same RBAC rules as API clients

### Developer Experience
- **Single binary** — Zero external dependencies, cross-platform (Linux, macOS, Windows)
- **Embedded admin UI** — connect databases with host, port, user and password (no connection strings), test before saving, browse schemas and data, build roles and keys, and copy ready-made MCP configs for Claude, Cursor, VS Code and more. Works offline; light and dark themes
- **SQLite config store** — All configuration stored locally, no external database required
- **npm + Homebrew + Docker** — Install in seconds on any platform (`npx @faucetdb/faucet`)
- **Health endpoints** — `/healthz` and `/readyz` for Kubernetes-style probes

---

## Supported Databases

| Database | Versions | Cloud Variants | Tutorial |
|----------|----------|----------------|----------|
| **PostgreSQL** | 9.6 – 17 | Amazon RDS, Aurora, Supabase, Neon, Azure Database | [Guide](https://wiki.faucetdb.ai/tutorial-postgres) |
| **MySQL** | 5.7 – 9.x | Amazon RDS, Aurora MySQL, PlanetScale, Azure MySQL | [Guide](https://wiki.faucetdb.ai/tutorial-mysql) |
| **MariaDB** | 10.2 – 11.x | Via MySQL driver | [MySQL guide](https://wiki.faucetdb.ai/tutorial-mysql) |
| **SQL Server** | 2012 – 2022 | Azure SQL Database, Amazon RDS | [Guide](https://wiki.faucetdb.ai/tutorial-sqlserver) |
| **Oracle** | 12c – 26ai | Oracle Cloud (OCI), Amazon RDS, Azure | [Guide](https://wiki.faucetdb.ai/tutorial-oracle) |
| **Snowflake** | Current | AWS, Azure, GCP | [Guide](https://wiki.faucetdb.ai/tutorial-snowflake) |
| **SQLite** | 3.35+ | Local file, in-memory | [Guide](https://wiki.faucetdb.ai/tutorial-sqlite) |

Connector details, SSL options and driver notes: [Database connectors](https://wiki.faucetdb.ai/database-connectors).

---

## 60-Second Quickstart

### Install

**npm (Node.js 18+):**
```bash
npx @faucetdb/faucet serve
```

**Homebrew (macOS / Linux):**