Usage is not success. Success is the migration shipping faster with equal or better quality, and the capability outliving the consultants.
Legacy developers active at target, week-8 retention at target, every guardrail green, organic adoption growing, context contributors above target.
Adoption moving, guardrails green or amber, fewer than eight weeks in (the J-curve dip is expected).
One guardrail red, or adoption stalled among legacy developers after eight weeks with nothing broken.
Two or more guardrails red. Throughput without control is "Legacy Bottleneck amplification", not adoption.
Individual AI-usage tracking gets gamed, creates backlash, and can fall under worker-management rules in the EU AI Act. Everything here is aggregated to team, tenure band and cohort.
All from git plus a roster. Vendor telemetry is optional enrichment.
Trailer AI-assisted: yes|partial. Fallback: a vendor Co-Authored-By or kernel-style Assisted-by line (counted as inferred).
≥1 AI-assisted commit in the trailing window (default 28 days). Engaged: ≥2 AI-active days in 28 (GitHub/DX definition). Frequent: ≥3 AI-active days per week over 4 weeks.
AI-active in ≥3 of the last 4 weeks and ≥50% of the developer's commits AI-assisted, with ≥3 commits.
Tenure at or above the configured threshold in the roster (default 5 years). Tenure bands: <3, 3-10, 10+ years.
Cohort = ISO week of first AI-assisted commit. Retained at +N weeks = still active in the 28 days ending then.
Per commit, share of its files touched again by another commit within 30 days. Cheap proxy for the 21-30-day rework metric.
Commits whose subject starts with "Revert" or whose body references a reverted commit, over all commits.
Mean of three coverages over AI-assisted commits: Context pinned to a sha, Verification present, Reviewed-by present.
AI-active developers whose roster cohort is empty or "organic": never in a Capisoft-led wave.