Build

Build with Blue

Choose a bounded use case, model the state, add one operation, and introduce providers, agents, payments, and document boundaries deliberately.

Open GitHub ↗

A successful first Blue application is small enough to explain completely. Do not start by encoding an entire enterprise process or loading every package.

Architecture

Build your first solution

Move from ordinary state to Channels, Operations, Messages, BEX, Mandates, providers, and separate documents.

Engineering

Implementations and GitHub

Find Java and JavaScript libraries, registries, fixtures, tests, and repository boundaries.

Quickstart

Start with one transition

Use the smallest executable example before choosing a full application architecture.

Recommended build order#

Model the shared state without contracts.
Define the participants and direct Timeline Channels.
Add one operation and deterministic handler.
Add typed Requests and Responses where communication matters.
Introduce BEX only for pure deterministic computation.
Add an agent before authority and show the attempt being withheld.
Add one narrow Operation Mandate.
Split a relationship into a separate document when its boundary differs.
Add providers for external facts instead of ambient I/O.
Add a second portal or implementation to prove portability.

Keep the sources of truth separate#

language.blue: explanation and patterns;
Playground: executable proof and inspection;
MyOS: product experience;
repo.blue: canonical package and type content;
GitHub: specifications, implementations, fixtures, and releases.