Streamlet is a standalone, stateless route-optimization service that solves vehicle routing problems (VRPs) with time windows and multiple refill stations, built on top of an external routing engine (Valhalla). It is consumer-agnostic: any client can submit a problem and get back optimized routes. Its first consumer is Green Ecolution.
| Method | Path | Description |
|---|---|---|
| POST | /v1/solve |
Solve a VRP and return optimized routes |
| GET | /health |
Liveness check |
| GET | /api-docs/openapi.json |
OpenAPI schema for the API |
Note: multiple depots are accepted in a problem, but routes always return to the first depot (current semantics).
Streamlet is configured entirely via environment variables:
| Variable | Default | Description |
|---|---|---|
STREAMLET_ADDR |
0.0.0.0:3000 |
Address/port the HTTP server binds to |
STREAMLET_VALHALLA_URL |
http://localhost:8002 |
Base URL of the Valhalla routing engine |
STREAMLET_ENGINE_TIMEOUT_MS |
10000 |
Timeout for requests to the routing engine |
STREAMLET_SOLVER_TIME_LIMIT_MS |
2000 |
Maximum solver time budget per solve request |
Alongside the service, the workspace ships pbf-patch, which patches an OSM
extract before tiles are built (blocked roads, footpaths opened for service
vehicles). Its input is plain GeoJSON, so any workflow can use it. See
crates/pbf-patch/README.md.
The project is a Cargo workspace with three crates: streamlet-core (domain
model and solver), server (HTTP API) and pbf-patch (tile-pipeline CLI).
# Build and test the whole workspace
cargo build --workspace
cargo test --workspace
# Run only the API (black-box) tests
cargo test -p server --test api
# Run the Solomon VRPTW regression benchmarks (release mode, with output)
cargo test -p streamlet-core --test solomon --release -- --nocaptureA Nix flake is provided for a reproducible development shell (Rust
toolchain, pkg-config, openssl, cargo-deny, cargo-edit, bacon,
rust-analyzer):
nix develop