Add support for running the MCP server over HTTP with Server-Sent Events
(SSE) using the MCP Streamable HTTP specification, alongside the existing
STDIO transport.
New features:
- Transport abstraction with Transport interface
- HTTP transport with session management
- SSE support for server-initiated notifications
- CORS security with configurable allowed origins
- Optional TLS support
- CLI flags for HTTP configuration (--transport, --http-address, etc.)
- NixOS module options for HTTP transport
The HTTP transport implements:
- POST /mcp: JSON-RPC requests with session management
- GET /mcp: SSE stream for server notifications
- DELETE /mcp: Session termination
- Origin validation (localhost-only by default)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
The connectionString option stores credentials in the world-readable
Nix store. This adds connectionStringFile as an alternative that reads
the connection string from a file at runtime, compatible with secret
management tools like agenix or sops-nix.
Changes:
- Add database.connectionStringFile option (mutually exclusive with connectionString)
- Read connection string from file at service start when configured
- Add warning to connectionString documentation about Nix store visibility
- Update README with examples for both approaches
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Module provides:
- services.nixos-options-mcp.enable - Enable the service
- services.nixos-options-mcp.package - Package to use
- services.nixos-options-mcp.database.type - sqlite or postgres
- services.nixos-options-mcp.database.name - SQLite filename
- services.nixos-options-mcp.database.connectionString - PostgreSQL URL
- services.nixos-options-mcp.indexOnStart - Revisions to index on start
- services.nixos-options-mcp.user/group - Service user/group
- services.nixos-options-mcp.dataDir - Data directory
Includes systemd hardening options.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
