OAuth 2.0 in the software development life cycle isn’t a checkbox. It’s the spine of modern authentication. Get it wrong and every sprint, every commit, every test loses meaning. Get it right and your app becomes a fortress that moves fast.
OAuth 2.0 lets applications access resources on behalf of a user, without giving away passwords. It uses tokens instead of secrets. It separates roles and flows: Authorization Code, Client Credentials, Implicit, Device Code. Each flow is designed for a precise use case—no more, no less. Choosing the wrong flow at any stage of the SDLC creates cracks that are hard to seal later.
From planning, define how authentication fits into business requirements. This is where the right flow is mapped to each client—mobile, web, internal services. In design, inject OAuth 2.0 into your architecture diagrams, not as an afterthought but as a core interface contract. This is the time to decide scope usage, refresh token policies, and secure storage for secrets.
During implementation, avoid hardcoding credentials. Use standard libraries that keep pace with the OAuth 2.0 specification updates and security advisories. Code review checklists should flag insecure redirect URIs, missing state parameters, and token misuse.