Quotation API

Quotations are a small but recurring requirement across products. Most implementations end up as a feature buried inside a larger system, with the contract designed around the immediate consumer.

This experiment pulls quotations out into their own service, so the contract can be designed once and reused.

• Designing a small, well-shaped API surface for a single concept (a quotation).
• Supporting multiple quotation types without the API becoming a mess of special cases.
• Practising backend architecture on a contained problem.
• Treating a small service as a product - versioning, contracts, evolution.

• A backend service that generates different types of quotations.
• A clean REST API surface for creating, reading, and managing quotations.
• Backend architecture designed to keep the service small and understandable.

Backend-first, with attention to the API contract and the shape of the underlying domain model.

• .NET and C# for the backend.
• REST API as the external contract.
• Internal structure designed around the quotation domain, not the immediate UI.

• Small services benefit from a disproportionate amount of contract design.
• Multiple quotation types are easier to model as a single concept with variants, not as parallel endpoints.
• A focused service is also easier to evolve, replace, or retire.

Active build. The next focus is on expanding the supported quotation types and tightening the API contract based on actual usage.