Deploy and Host Postgres MCP on Railway

Postgres MCP is a Model Context Protocol server that exposes a PostgreSQL database to LLM clients as tools — database health checks, query plan analysis, index tuning, and constrained SQL execution. This template deploys the MCP server behind an nginx bearer-token auth gateway, so an LLM can safely talk to your database from a publicly reachable endpoint.

About Hosting Postgres MCP

The upstream project has no built-in client authentication, so this template places an nginx service in front that validates every request against a comma-separated list of bearer tokens before proxying to the MCP over Railway's private network. The MCP can be pointed at any PostgreSQL-compatible database — a Railway Postgres plugin you add to the project, a managed cloud database (Supabase, Neon, RDS), or a self-hosted instance.

Common Use Cases

Give Claude, Cursor, or other MCP clients read-only access to a production database
Let an agent profile slow queries and recommend indexes without giving it a raw connection string
Retrieval-Augmented Generation (RAG) over relational data
Secure sharing of a database tool endpoint with teammates via a bearer token

Dependencies for Postgres MCP Hosting

The template ships the nginx auth gateway and the Postgres MCP server. You bring the database: add a Railway Postgres plugin to the same project after deploy, or point the MCP at any external PostgreSQL instance via DATABASE_URI.

Deployment Dependencies

A postgresql://user:pass@host:port/dbname connection string for the database the MCP should expose.

Implementation Details

Architecture Components

This template deploys two services:

Gateway: nginx:alpine with a public Railway domain. Validates Authorization: Bearer against API_KEYS and proxies the rest to the MCP over Railway's private network with SSE-friendly settings.
Postgres MCP: the crystaldba/postgres-mcp server (pinned to v0.3.0) running in SSE transport mode. No public domain — reachable only via mcp.railway.internal:8000.

Authentication

Clients must send Authorization: Bearer where `` is one of the comma-separated entries in API_KEYS. Generate keys with openssl rand -hex 32; rotating is a variable update + gateway redeploy. Defense-in-depth is provided by ACCESS_MODE=restricted on the MCP, which forces read-only transactions and rejects commit/rollback even if a key leaks.

Service Configuration

MCP endpoint: https:///sse.
Database: set DATABASE_URI on the MCP service. If you add a Railway Postgres plugin to the same project, use ${{Postgres.DATABASE_URL}} as a reference variable; otherwise paste an external connection string.
Access mode: ACCESS_MODE=restricted (default) for read-only with execution-time limits, or unrestricted for full read/write — recommended only for dev/throwaway databases.

License Information

MIT (postgres-mcp) + BSD-2-Clause (nginx).

Why Deploy Postgres MCP on Railway?

The auth gateway, private-network wiring, and SSE passthrough are all pre-configured — giving an MCP client secure access to a Postgres database is a one-click deploy instead of a custom nginx + reverse-proxy project.

Notes

Source repo: https://github.com/FournyP/postgres-mcp-railway-template
Upstream MCP server: https://github.com/crystaldba/postgres-mcp
Model Context Protocol: https://modelcontextprotocol.io