Heatmap · Diagram Design
CI failure rate (%) by service and sprint, six sprints. payments spiked to 47% in S4 — a deploy regression that slipped through the gate — and had recovered to 4% by S6. billing carries the highest structural rate; notifications is the quietest service throughout.
Focal · payments · S4
A CI gate misconfiguration during the payments S4 deploy let a breaking change through. The spike resolved by S6 after the rollback and a gate fix, returning to a 4% baseline.
Structural issue · billing
billing shows the highest non-focal failure rates across all six sprints, peaking at 9% in S3. This is a persistent structural issue unrelated to the payments regression.
Quietest service · notifications
notifications stayed at or below 2% every sprint. This is the contrast the heatmap makes visible: same period, same team, dramatically different structural rates.