What makes a good Solution Architecture Document — and what makes one nobody reads

A Solution Architecture Document (SAD) is only valuable if your development team can build from it. The best SADs are opinionated, specific, and honest about trade-offs. The worst are comprehensive, impeccably formatted, and immediately obsolete.

What a good SAD covers

At minimum: the business context, the solution overview, the component architecture, the integration design, the non-functional requirements (performance, security, scalability, availability), the key architectural decisions and their rationale, and the risks.

The most common mistakes

Over-engineering the documentation while under-specifying the decisions. Writing for approval rather than for the people who will build the system. Treating the SAD as a one-time artefact rather than a living document that evolves with the solution.

The best test of a SAD: hand it to a senior developer with no context and ask them to describe back the system they would build. If they can't, the document has failed its purpose.