CI history window

A CI history window is the span of past pipeline data a CI analytics tool retains and lets you query — the maximum lookback available to dashboards, trend lines, and reports. A 7-day window answers "what broke this week"; only a longer one can answer "is this getting worse".

How it works

Three properties define a window, and vendors vary on all of them:

Length differs by orders of magnitude across tools and plan tiers — some free plans retain barely a day of data (Mergify's free tier is 24 hours, as of 2026-07-28) while enterprise observability platforms keep pipeline history for over a year — Datadog retains pipeline, stage and job data for 15 months (as of 2026-07-28) — so it is one of the first things to check when comparing tools. Backfill decides whether you see trends on day one or wait weeks for data to accumulate. The past-the-edge behavior is the quiet one: deletion means a downgrade or lapsed trial destroys history, while a pure visibility clamp means the data survives and reappears when the window widens.

Why it matters

Most of the metrics worth tracking are only meaningful against a baseline, and the baseline lives in the window:

• Trend direction. Whether a failure rate of 12% is a crisis or a recovery depends entirely on what the prior weeks looked like.
• Flaky vs broken. Separating flaky tests from genuine regressions requires seeing the same job pass and fail across many runs — a short window rarely holds enough samples.
• Slow drifts. Duration percentiles creeping up 2% a week are invisible in any single week.
• Sparse events. MTTR and change failure rate average over incidents, and a small team may see only a handful per month — a window shorter than the gap between incidents produces noise, not a metric.

The practical rule: the window must be several times longer than the cycle of the pattern you are trying to see. Weekly release rhythm needs a month or more of history; monthly patterns need a quarter.

TrimCI treats plan limits as visibility windows in the strict sense — synced runs are never deleted and syncing never stops, so a wider plan window immediately exposes history that was already there. The per-plan window lengths, and the 60-day maximum lookback that currently bounds all of them, are listed on the pricing page.