Developer Guide

This section covers the internals of winterbaume for contributors who want to implement new services, extend the code generator, write tests, or add pluggable backends.

Contents

• Architecture — component model, request flow, core traits
• Adding a Service — step-by-step guide for new service crates
• Smithy Codegen — generating model.rs and wire.rs from Smithy models
• Testing — integration tests, moto parity ports, Terraform E2E suites
• Backends — implementing pluggable storage and query-execution backends

Quick orientation

winterbaume/
  crates/
    winterbaume-core/     # shared traits, BackendState, MockAws builder, Vfs/BlobStore
    winterbaume-{svc}/    # one crate per AWS service
    winterbaume-server/   # standalone HTTP server (hyper)
    winterbaume-stubs/    # 501 fallback for unmapped services
    winterbaume-*-redis/  # optional Redis persistence crates
    winterbaume-sqlengine-duckdb/  # optional DuckDB query backend
    winterbaume-partiql/  # DynamoDB PartiQL parser
    winterbaume-terraform/ # Terraform provider compatibility
  tools/
    smithy-codegen/       # generates model.rs + wire.rs per service
  vendor/
    moto/                 # reference Python moto (git submodule)
  tests/
    e2e/terraform/        # Terraform E2E test suites

Where to start

Goal	Start here
Understand the overall design	Architecture
Add a new AWS service	Adding a Service
Fix a generated serialiser	Smithy Codegen
Add tests for a service	Testing
Add a Redis or DuckDB backend	Backends