We adopted a writing culture where every significant technical decision gets documented in a lightweight RFC. These aren’t formal or bureaucratic — just a shared Google Doc with problem statement, proposed approach, alternatives considered, and decision rationale. Six months in, the archive has become our most valuable knowledge base.
Authentication turned out to be the most politically charged decision in the entire project. Every team had opinions about OAuth providers, session management strategies, and token lifetimes. We eventually settled on a pragmatic middle ground that nobody loved but everyone could live with.
The hardest part of any migration is the data. Not the schema changes — those are mechanical. The real challenge is ensuring data integrity during the transition period when both old and new systems are running simultaneously and writes need to be consistent across both.
Feature flags transformed our release process more than any CI/CD improvement. Decoupling deployment from release meant we could merge code daily, test in production with internal users, and gradually roll out to customers — all while maintaining the ability to instantly revert without a code deployment.
What worked for us won’t work for everyone. Context matters enormously. But we hope sharing our experience saves someone else from repeating our more expensive mistakes.