At a glance
What you need to know.
Architecture documentation should help a team understand a system, change it safely and recover when it fails. This public guidance describes a practical document set. It is not a statement that the illustrated structure matches every APPNEURAL product or a customer's deployed environment.
Begin with the context and scope
Write a short statement of the problem, users, critical journeys and the system boundary. List external providers and internal teams that own dependencies. Mark assumptions and unresolved constraints so reviewers can challenge them before implementation. A context diagram should show relationships without hiding them behind vendor names. Include the environment and version the document describes. Distinguish the proposed design from observed production behavior; readers should not have to guess whether a diagram is a plan or verified current state.
Document components through responsibility and data ownership
For each meaningful module or service, identify its purpose, owner, authoritative records and interfaces. Explain which component may change a record and how other components obtain information. Mark caches, indexes and reporting copies as derived state. A deployment boundary and a business boundary are related decisions, but they are not automatically the same. Keep names consistent across diagrams, code and operating notes. Avoid inventing a separate service merely to make the diagram appear comprehensive.
Describe a successful flow and its important failures
Follow one critical request from authentication through authorization, persistence and any downstream handoff. Note the point at which a user receives confirmation and what that confirmation promises. Add the cases for repeated requests, missing permission, slow dependencies and partial completion. Show where retries are allowed and where a person resolves an exception. This detail helps uncover mismatched expectations between teams. A sequence diagram is useful when ordering matters, but plain steps can be sufficient for a simple path.
Keep decision records focused on tradeoffs
Record the context, alternatives, decision, consequences and conditions that would trigger a review. Useful topics include service boundaries, storage, tenant isolation, integration contracts and recovery. State why the chosen option fits current constraints instead of claiming that it is universally best. Link a decision to the affected components and acceptance evidence. A rejected alternative matters when it explains cost or risk; an exhaustive technology comparison can obscure the actual reason the team chose its approach.
Connect the design to a reproducible release
Document environments, required dependencies, deployment authority and configuration names without including secret values. Describe migrations, domain routing and compatibility during rollout. Record how to identify the running version, verify a real user journey and roll back or repair a failed change. Include backup restoration and operational escalation where the system requires them. A successful build is evidence about a build; the release record needs separate evidence for the deployed environment and the dependencies that journey uses.
Assign maintenance to the people changing the system
Keep source diagrams and decision notes in a location reviewed with relevant code changes. Give the document an owner and a practical review trigger, such as a changed contract, data model or deployment route. Remove obsolete assertions rather than accumulating conflicting descriptions. Link public developer resources for general context and product-specific evidence where available. For external reviews, prepare a redacted version that preserves boundaries and tradeoffs without exposing credentials, private records or sensitive infrastructure details.
Before you start.
- State whether the document describes proposed or verified current behavior.
- Identify users, external dependencies and system scope.
- Assign component responsibilities and authoritative records.
- Explain confirmation, retries and partial failure in critical flows.
- Record tradeoffs, review triggers and deployed-version evidence.
- Keep documentation ownership aligned with code and operating changes.
Common questions.
Is a diagram enough for an architecture review?
Usually it needs supporting context, data ownership, important flows and decision notes. A diagram shows relationships; it rarely explains every permission, consistency assumption or recovery action needed to evaluate the design.
Should public documentation reveal the whole infrastructure?
Publish the context needed for users and evaluators without exposing secrets or sensitive operating detail. Internal runbooks can contain authorized environment-specific information. Keep public claims consistent with the verified product scope.