Code review

Time to first review

Also known as First review latency, Time to initial review

By WeavePublished 2 min read

Definition

Time to first review is the elapsed time between a reviewable change being submitted and the first substantive reviewer response.

What the measure captures

Time to first review is the elapsed time between a reviewable change being submitted and the first substantive reviewer response. It is most useful when the team states the unit of analysis, the start event, the completion event, and the population being measured. A review request, a pull request, and a merge are related events, but they are not interchangeable. Keeping those boundaries visible prevents a dashboard from turning an operational signal into an unexplained score.

A practical example

A team can distinguish a quick automated acknowledgment from a human comment that examines behavior, then report both intervals separately. Start with a small sample and inspect the underlying requests before creating a target. Record the repository, change type, reviewer path, and relevant policy state. That makes it possible to explain an unusual result instead of simply celebrating or escalating a number. Compare similar work over time and annotate major changes in ownership, branch rules, or automation.

How to use it carefully

The start event must be defined carefully. Including draft time or excluding weekends can change comparisons between teams. Review metrics work best as prompts for team-level investigation. Combine them with review samples, author and reviewer feedback, escaped defects, rework, and delivery outcomes. Avoid ranking individuals from a single measure because review difficulty, system familiarity, and assignment patterns vary. A healthy process makes useful feedback available at an appropriate time while preserving accountability for the final change.

How this relates to Weave

Weave can connect review events with change context and delivery signals so teams can inspect time to first review alongside review time, pull request size, and flow. That context helps teams investigate queues and quality patterns without treating one review number as a verdict on an engineer.

How this relates to Weave

Weave can connect review events with change context and delivery signals so teams can inspect time to first review alongside review time, pull request size, and flow. That context helps teams investigate queues and quality patterns without treating one review number as a verdict on an engineer.

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Sources and further reading

  1. Reviewing changes in pull requests, GitHub Docs