Collaboration & Process › Agile & Delivery Process

Software Development Lifecycle

The stages from idea to production to maintenance.

Also known as: SDLC, software lifecycle

The software development lifecycle (SDLC) describes the stages software goes through: gathering requirements, designing, implementing, testing, deploying and maintaining it. Those stages happen in every project, though teams group and order them differently.

requirements -> design -> implementation -> testing -> deployment -> maintenance

Older models, such as the waterfall model, run these stages in a strict sequence. Agile approaches repeat them in short cycles, so each increment goes through a small version of every stage. Many teams use a mix.

The classic mistake is treating the stages as strictly sequential and forgetting maintenance. In practice, maintenance is often where most of the time goes: bug fixes, dependency updates, and changes that users request after launch. Plan for it from the start, including monitoring and the CI pipeline that keeps releases repeatable.