Review Timezone Coverage measures the availability of qualified code reviewers across the team's spread of working hours. Gaps in coverage mean that PRs opened near the end of one timezone's workday may sit unreviewed until the next day, adding significant latency to the development cycle. Good timezone coverage ensures that review turnaround remains consistent regardless of when code is submitted.
Whether review capacity exists in each timezone to avoid 24h round-trips. If all senior reviewers for a shared library are in one TZ, every PR from other TZs faces 12h+ review latency. Follow-the-sun review rotation (designated reviewers per TZ) can cut this to 2-4h.
If all reviewers are in one timezone, every PR from other TZs faces 12h+ latency. Follow-the-sun review rotation cuts this to 2-4h but requires scale to staff.
Designated reviewers per TZ cut review latency from 12-24h to 2-4h. Follow-the-sun rotation is primary mitigation.
Review capacity in every TZ means PRs don't wait for a specific TZ to wake up. Reduces primary handoff bottleneck.
Devs feel supported rather than blocked. PRs get reviewed during their working day, not 12h later.
Continuous review coverage means PRs progress around the clock instead of stalling at TZ boundaries.
Domain expert reviewers per TZ means code reviewed by people who understand it, not just whoever is online.