lite-bootstrap 1.3.0

Lightweight bootstrap for production-ready Python microservices

lite-bootstrap wires production observability — OpenTelemetry, Prometheus, Sentry, and structlog — into FastAPI, Litestar, and FastStream services in a few lines, with no boilerplate.

With lite-bootstrap, you receive an application with lightweight built-in support for:

• sentry
• prometheus
• opentelemetry
• pyroscope - with OpenTelemetry trace-profile linking
• structlog
• cors
• swagger - with additional offline version support
• health-checks

Those instruments can be bootstrapped for:

• LiteStar
• FastStream
• FastAPI
• FastMCP
• services and scripts without frameworks

Lifecycle constraints

A few constraints that aren't obvious from the API:

• One bootstrapper per application instance. Constructing two FastAPIBootstrappers around the same fastapi.FastAPI (or two FastMcpBootstrappers around the same FastMCP) stacks teardown hooks and re-wraps the lifespan. The library warns and skips the second attachment, but the second bootstrapper's teardown() won't fire on ASGI shutdown.
• One OpenTelemetryInstrument per process. bootstrap() calls opentelemetry.trace.set_tracer_provider(...), which the OTel SDK enforces as set-once — subsequent calls log a warning and have no effect. teardown() flushes spans and closes exporters but can't reset the process-global pointer.
• teardown() is idempotent. BaseBootstrapper.teardown() short-circuits if not bootstrapped; per-instrument teardown methods are safe to call multiple times.
• Partial teardown failures are aggregated. If an instrument's teardown raises, the bootstrapper continues with the rest of the instruments and raises TeardownError at the end with all collected failures.

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Usage examples:

• with LiteStar - litestar-sqlalchemy-template
• with FastAPI - fastapi-sqlalchemy-template

Acknowledgements

lite-bootstrap is inspired by microbootstrap — a single package that wires up the common observability stack (sentry, prometheus, opentelemetry, logging, cors, swagger, health-checks) for FastAPI / Litestar / FastStream services and for plain scripts.

The following ideas were borrowed:

• the overall surface — a Bootstrapper per framework that composes a set of instruments,
• the lifecycle model — each instrument has bootstrap() / teardown() / is_ready() and is skipped when its optional dependency is not installed,
• the catalog of supported instruments and supported frameworks.

The following intentionally differ:

• Configuration: lite-bootstrap uses frozen dataclass configs (no pydantic / pydantic-settings runtime dependency), which is what makes it "lite". microbootstrap configures everything through pydantic-settings models.
• Granular extras: lite-bootstrap has no mandatory runtime dependencies; every instrument (sentry, otl, logging, pyroscope) and every framework (fastapi, litestar, faststream) is its own extra, plus an opt-in orjson speedup for logging, per-pair combos (fastapi-sentry, litestar-otl, faststream-metrics, …) and *-all rollups. You install only what you actually use. It also runs on free-threaded CPython (3.13t/3.14t) — see architecture/free-threading.md. microbootstrap bundles the full observability stack (opentelemetry, sentry-sdk, structlog, pyroscope-io, rich, pydantic-settings, …) as base dependencies and only splits framework packages into extras.
• Scope: lite-bootstrap is deliberately narrow — only instrument wiring. It does not include a Granian server runner or a console writer.

📚 Documentation

📦 PyPI

📝 License

Part of modern-python

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