Tech Debt Weekly

Dark folds of cloth lit along their edges by a soft ember glow

migrationsLinkOct 27, 2026github.blog ↗

From 2,500 requests to 24: Rebuilding star history without the stargazers

Seven glowing wireframe cubes in a row on a dark blue field, linked by streams of light flowing through the center cube

toolingOct 20, 2026

7 ETL Tools Built for Real-Time Data Integration

How we rebuilt complex permissions without migrating to Zanzibar

Zanzibar would have meant rewriting every permission check and a new stateful service for each self-hosted customer. Infisical layered folder grants on the old model.

strategyLinkOct 7, 2026infisical.com ↗

Migrating Functionality Between Large-scale Production Systems Seamlessly

Uber moved authorization holds out of eight services by shadowing live traffic and diffing every call. Validation found dozens of mismatches before 0.25% of users moved.

migrationsLinkOct 7, 2026uber.com ↗

Migrating the GitHub Copilot runtime to Rust, using Copilot

One engineer plus agents ported GitHub's Copilot runtime to Rust in 14.5 weeks without pausing releases: 128 PRs, 135 releases, and dozens of regressions on the bill.

migrationsLinkOct 7, 2026github.blog ↗

The incremental migration playbook: derisk, enable, finish

A big-bang cutover needs every team ready on the same day; an incremental migration needs one team ready at a time. The patterns, the tooling, the long tail, and the honest ledger for a rewrite.

migrationsAug 24, 202610 min read

How to talk about debt with people who don't read code

The debt metaphor stopped working when it became a synonym for code we dislike. Debt as lead time and blocked features, repair budgets without a turf war, and what to say in planning.

cultureAug 23, 20269 min read

The Economic Benefit of Refactoring

A 17,155-line file cost an agent 159,564 input tokens per change. Fifteen refactoring steps cut that by 83% — repair work priced per future change, not by feel.

strategyLinkAug 20, 2026martinfowler.com ↗

How is the Bun Rewrite in Rust Going?

Bun's Rust rewrite was sold as 11 days and $165k. Ten weeks on there is no release, 2,475 bot PRs are queued, and the merge backlog alone is 86 days. The accounting every rewrite claim owes you.

migrationsLinkAug 20, 2026lockwood.dev ↗