Rust/Actix-web 4 implementation for the Rinha de Backend 2024/Q1 challenge with SQLx async driver and PostgreSQL stored procedures

Live demo → | Documentation →

A Rust implementation of the Brazilian backend challenge Rinha de Backend 2024/Q1, where a fictional bank API must handle concurrent transactions under strict resource constraints (1.5 CPU, 550MB RAM total). The current API is a single src/WebApi/main.rs entrypoint (173 total lines at this revision) using Actix-web 4 with the Tokio runtime and SQLx 0.8 for PostgreSQL access.

NGINX (:9999, least_conn)
├── webapi1-rust (:8080, 0.4 CPU, 100MB; host :6968 in dev)
├── webapi2-rust (:8080, 0.4 CPU, 100MB; host :6969 in dev)
└── PostgreSQL (0.5 CPU, 330MB)
    ├── InsertTransacao() — atomic balance update + validation
    └── GetSaldoClienteById() — statement with JSONB aggregation

• Single Rust API entrypoint (src/WebApi/main.rs, 173 total lines at this revision)
• Actix-web route handlers for transactions, statements, and /healthz
• SQLx compile-time query validation with offline cache (src/WebApi/.sqlx/)
• PostgreSQL stored procedures for server-side balance updates and statement aggregation
• UNLOGGED Clientes and Transacoes tables for challenge-oriented write throughput
• Lazy static HashMap for the five seeded client limits (no DB round-trip for client existence checks)
• PostgreSQL tuned for benchmark throughput: synchronous_commit=0, fsync=0, full_page_writes=0
• Multi-platform GHCR release flow: latest is assembled as a multi-arch manifest from amd64 and arm64 builds; latest-arm64 is also pushed during the arm64 leg
• Development observability stack with Prometheus, Grafana, InfluxDB, and postgres-exporter
• Committed stress-test report artifacts under docs/public/reports/; treat generated reports, not hard-coded README numbers, as the performance source of truth

• Docker with Docker Compose

git clone https://github.com/jonathanperis/rinha2-back-end-rust.git
cd rinha2-back-end-rust
docker compose up nginx -d --build

API available at http://localhost:9999.

The dev compose file also exposes the API instances directly on localhost:6968 and localhost:6969; use the NGINX port (9999) for challenge-compatible requests.

Transaction payload validation is handled in Rust before the stored procedure call: tipo must be c or d, descricao must be non-empty and at most 10 characters, and valor must be positive.

docker compose up k6 --build --force-recreate

The dev compose path runs k6 in MODE=dev with InfluxDB/Grafana export. The production compose file used by the release workflow runs k6 in MODE=prod and exports an HTML report artifact.

rinha2-back-end-rust/
├── src/WebApi/
│   ├── main.rs              # Complete API entrypoint (173 total lines at this revision)
│   ├── Cargo.toml           # Rust 2024 package and dependencies
│   ├── Dockerfile           # Multi-stage: rust:1.95 → debian:bookworm-slim
│   └── .sqlx/               # SQLx offline query cache
├── docker-entrypoint-initdb.d/
│   └── rinha.dump.sql       # UNLOGGED schema + stored procedures + seed data
├── docker-compose.yml       # Dev stack: APIs, PostgreSQL, NGINX, observability, k6
├── prod/docker-compose.yml  # Release/load-test stack using GHCR images and prod k6 mode
├── nginx.conf               # Load balancer config
├── docs/                    # Astro/Bun GitHub Pages site and wiki markdown
├── scripts/check_docs_drift.py # Source-backed README/wiki drift guard
└── .github/workflows/       # build-check, main-release, deploy, codeql

Docker image: ghcr.io/jonathanperis/rinha2-back-end-rust:latest

README and wiki facts that mirror code, Docker, Compose, or workflow state are checked by:

python3 scripts/check_docs_drift.py

The guard verifies high-value source-backed facts such as API line count, Docker builder version, Rust edition, endpoint coverage, workflow triggers, wiki navigation coverage, and known-stale phrases.

MIT — see LICENSE