@GergelyOrosz ·
How did Google refactor 250M lines of C++ code, pre-AI, what happened when Search could no longer ship on the regular cadence due to regressions, and why is it time to completely redo the CS curriculum? With @TitusWinters. Timestamps:
00:00 Intro 07:01 Getting hired by Google 09:48 Finding his niche at Google 14:32 Why Google made testing mandatory 17:45 Why new engineers fear making mistakes 20:40 Abseil: C++ foundations at Google 23:09 Google’s massive C++ refactoring 30:48 AI for rewrites 39:07 Software Engineering at Google: the book 43:10 Google’s readability reviews 47:18 Why teams still matter 52:41 Psychological safety 58:17 Layoffs and culture 1:02:11 Measuring developer productivity 1:11:17 Rethinking CS education 1:22:56 What new grads should learn 1:32:08 Titus’s ideal software engineering curriculum 1:36:27 Advice for breaking into tech 1:38:35 Book recommendation
Brought to you by:
• @turbopuffer – vector and full-text search engine built on object storage. It’s fast, cheap, and extremely scalable. http://turbopuffer.com/pragmatic
• @linear – one of the big challenges for us devs is the sheer amount of code to review. Linear Diffs is a new feature to review PRs inside of Linear, with all the context in one place. It also supports stacked PRs. https://linear.app/pragmatic
• @WorkOS – WorkOS built Airlock, the authorization layer for AI agents. It evaluates every request against the agent’s intent + your rules and either allows it, denies it, or routes it to a human. http://workos.com/airlock
Three interesting details:
1. Google made automated tests mandatory after Search could no longer ship regularly.
Around 2007, Search, the flagship product, was unable to ship at a monthly cadence any more, and the best they could ship to production was quarterly. Almost every change at Google touched Search’s code, even things like a change to Gmail. To clamp down, Google, as an org, mandated that every change was to be accompanied by a test. Over time, Search returned to its former higher cadence.
2. Google’s readability program might have been the largest educational program ever in tech.
To make a code change at Google, two people need to sign off that change through a code review:
a) An “owner” of the file/project: someone on the team with domain knowledge
b) A “readability” reviewer: an engineer certified to be a “readability” expert in the given language that the change was made in
Google’s first engineer, Craig Silverstein, walked each new dev hire through their first change. Java teams turned this approach into mentoring, where experienced reviewers were assigned to review all changes in a round-robin fashion. And soon enough, a formalized readability program was built for all languages. When Titus left Google three months ago, 10,000+ engineers were enrolled in readability at any given time. Has there ever been a bigger engineering “classroom” anywhere else?
3. Burn down the US undergrad CS curriculum (most of it)
Titus was the only working engineer on the steering committee for the ACM/IEEE/AAAI CS curriculum guidelines in 2023, and believes the curriculum is hopelessly out of date. He accuses it of not having altered substantially since around 2000, while the industry has. Testing and verification are cited as mattering a lot more for new joiners, but they are absent from the curriculum. Unless major changes are made to make it relevant, computer science enrollment could fall and software engineering programs that focus on practical dev skills will be attractive to students – this is Titus’s forecast.
