microvms-core

The client library for AWS Lambda MicroVMs: the control plane, the in-VM session surface, the cost engine, and the sizing model.

The type system carries every trap closure. A constraint the platform enforces at runtime — a size class that does not exist, a region that does not offer the service, a token that must not reach a log line — is a shape this crate refuses to construct rather than a check a caller can forget. docs/PLATFORM.md records the measured findings each one closes, with a date, a region, and an API version.

Money is rust_decimal, not f64. The ARM rates are figures like 0.0000276944, and summing a few thousand of them in binary floating point drifts toward a bill nobody can reproduce.

Position in the stack

microvms-cli ──▶ microvms-core ──▶ microvms-protocol
                       ▲
        microvms-py ───┴─── microvms-js

Nothing depends on the CLI. That direction is asserted mechanically by microvms-cli/tests/dependency_direction.rs rather than documented and hoped for.

Reading

• docs/TRUST.md — the threat model and the trust boundary
• docs/PLATFORM.md — measured platform behavior
• docs/EMBEDDING.md — using this crate from a host application

License

Apache-2.0