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We’d put it off for a year. I read one pull request, asked Reviewer one question and merged it after lunch.
Jonas Verhey
CTO, Halden
The goal
Halden charges 40,000 customers every month. Moving them to Payment Intents meant touching every billing path while the old webhooks kept working until March.
The run
Reader mapped 1,204 files and 38 call sites in billing.
Planner split the goal into 1,024 tasks across nine waves.
Guard blocked one key before it reached the branch.
What changed
The pull request was 41 files with two new tests. Jonas merged it the same day, and the old webhooks kept working until March, as asked.