Clear modules and boundaries
Focused components make responsibilities clear and limit the impact of changes.
Maintainable Software
Software that people can understand, repair, and adapt as their needs change.
In plain language
Maintainable software is easy to understand and change, with clear code, useful documentation, and reliable checks.
Use enough structure for likely changes while keeping complexity and upkeep manageable.
The foundation
What matters in Maintainability
Checks people can rely on
Types, tests, and automated checks help catch regressions.
Understandable ownership
Keep documentation and decisions accessible beyond the original developer.
Applied by The Forge
How we put it into practice
We match the software’s structure to the team’s capacity to maintain it.
Design around responsibilities
Organise code around clear responsibilities.
Reuse with intent
Share repeated functionality while keeping product-specific behaviour close to its use.
Keep changes small and checked
Small changes and focused checks make defects easier to find.
Maintain the operating knowledge
Keep dependency, deployment, and recovery documentation current.
A useful boundary
Limits to keep in mind
- It does not mean the software will never need maintenance or redesign.
- It is not achieved by adding abstractions, patterns, or documentation everywhere.
- Clean-looking code alone is insufficient if the product cannot be tested, deployed, or understood safely.
A concrete example
One capability, many products
A shared address component has clear inputs and focused tests. Fixing its validation benefits every product that uses it.
Further reading
Primary sources
Check the sources behind these explanations.
Related concept
Accessibility: Web Accessibility
Designing and building websites that people with disabilities can perceive, operate, understand, and use with assistive technologies.