Grab

App stability at scale with a layered defense

With many engineers and AI-assisted code landing in a weekly release of a superapp that has millions of lines of Android code, Grab stops crashes in layers. Lint rules (including custom ones written after post-mortems) and tests block merges, a mandatory one-week Grab Early Access build catches crashes before production, and a staged rollout over a week is automatically paused when the new version's crash rate looks abnormal. In production, on-call engineers first flip feature flags, then try server-side fixes, then hotfix, helped by a flag-rollout history dashboard and Crashlytics data exported to BigQuery.

Published
2026-10-21
Scale
millions of lines of Android code, 100M+ Google Play downloads, weekly release cycle
Techniques
shift-left testing staged rollout feature flags crash triage
Stack
Android iOS Firebase Crashlytics BigQuery

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