Cipher — distributed Secret Rotation Service

code review
1

Hi everyone,

I'd appreciate a code review of my project Cipher — a distributed Secret Rotation Service built as a capstone project for RustCamp UA certification.

Repo: GitHub - misikdmytro/cipher · GitHub
PR with full implementation: cipher by misikdmytro · Pull Request #1 · misikdmytro/cipher · GitHub

What it does

Cipher automates rotation of secrets stored in AWS Secrets Manager. It's split into 4 services in a Cargo workspace:

  • API — HTTP REST (Actix-web), owns secrets metadata & webhook CRUD
  • Scheduler — orchestrates rotation schedules, publishes events via RabbitMQ
  • Rotator — stateless worker, executes actual rotation against AWS (blue/green strategy), publishes status events
  • Notificator — consumes rotation events, delivers webhook notifications

Services talk to each other over gRPC (sync) and RabbitMQ/AMQP (async events). PostgreSQL via sqlx for persistence.

Stack / crates

Actix-web, tonic (gRPC + protobuf), sqlx (Postgres), lapin (RabbitMQ), AWS SDK, tokio, tracing, utoipa (OpenAPI docs).

What I'm looking for feedback on

  1. Overall architecture — does the service decomposition and communication pattern (gRPC + AMQP) make sense? Anything over-engineered or missing?
  2. Idiomatic Rust — trait usage, error handling, module structure, anything that smells off
  3. Domain modeling — the domain crate, how types and boundaries are defined
  4. Async patterns — task spawning, graceful shutdown, RabbitMQ consumer lifecycle
  5. Testing approach — integration test setup, mocking strategies

This is a learning project, so don't hold back — blunt feedback is welcome.

Thanks!