What Is Trunk-Based Development? | Vantage

Trunk-Based Development Trunk-based development (TBD) is a source control workflow where all engineers commit directly to a single shared branch (the trunk or main) rather than maintaining long-lived feature branches. Changes are small and frequent — typically multiple times per day per engineer. Commits are kept small enough to be integrated and deployed the same day they are written. Feature flags are used to hide incomplete work from production users while allowing code to be shipped continuously.

Why trunk-based development matters

Long-lived branches are the primary source of integration conflicts and delayed feedback. When a feature branch lives for two weeks, the merge is painful — dozens of competing changes collide, and the integration cost is high. Trunk-based development eliminates this by keeping branches short (hours, not days) and integrating continuously. DORA research consistently shows TBD as one of the strongest predictors of software delivery performance.

How it works

Engineers create short-lived branches (less than one day to two days) and commit frequently. Feature flags hide incomplete work from users. Automated CI runs on every commit. Pull requests are reviewed and merged the same day they are opened. Trunk is always deployable. Releases are decoupled from deploys — you can ship code to production without turning on the user-facing feature. This allows continuous integration without continuous feature release.

Common mistakes

• Long-lived feature branches defeat the purpose — if a branch lives more than two days, it is no longer trunk-based development

• No feature flags for incomplete work — you cannot ship a half-built feature without a mechanism to hide it

• Insufficient test coverage — TBD only works if every commit is covered by automated tests that run in CI

• No code review discipline — small frequent PRs still require review; without it, quality degrades quickly

• Confusing TBD with no branching — short-lived branches are still branches; the key is the lifetime, not the existence