QueryAPIGate is a self-hosted service that turns saved SQL queries into versioned, governed REST endpoints. It connects to databases including PostgreSQL, MySQL, ClickHouse, SQLite, DuckDB, H2, MongoDB and generic JDBC sources, and can query Parquet, CSV and JSON files through DuckDB. Its built-in console provides SQL editing, schema browsing, query testing and API publication.
Each saved query becomes a versioned endpoint with typed, injection-safe parameters, field-level validation, pagination, streaming exports and response formats including JSON, NDJSON, XML, YAML, CSV, TSV, Excel and Parquet. The service includes API-key authentication, scoped permissions, roles, collections, rate limits, IP restrictions, optional JWT-based sign-in, SQL-guarded execution, connection pooling, caching, run history, audit logs, OpenAPI output, Prometheus metrics, live SSE events and an administrative UI. It can also expose saved queries as MCP tools for AI agents.
QueryAPIGate is distributed as a Python package and Docker images. The repository describes it as source-available under the Functional Source License 1.1 with the MIT Future License; it is not currently an OSI-approved open-source license, and versions become MIT-licensed two years after release.