Why performant code matters (but gets widely ignored), with Casey Muratori

Categories: Product, Startup

Summary

Most software runs 10-100x slower than necessary because developers abandoned performance optimization as a discipline. Casey Muratori argues that 'premature optimization' wisdom is misused as an excuse to ignore performance entirely, and learning assembly language is far more accessible than developers assume.

Key Takeaways

  1. Most software in production runs 10-100x slower than it needs to, indicating systemic neglect of performance as a core engineering discipline rather than isolated cases.
  2. Performance optimization isn't a mystical process—it requires profiling to identify bottlenecks, making targeted changes, then measuring results. Most developers skip this systematic approach entirely.
  3. Assembly language has only 20-30 instructions to learn for practical high-performance work, making it more accessible than mastering CSS or React—demystify it as a legitimate tool for serious engineers.
  4. The 'premature optimization is the root of all evil' maxim is widely misused as justification to avoid thinking about performance architecture when it should inform design decisions upfront.
  5. Challenge received programming wisdom directly—much conventional advice is untested dogma. Question industry consensus on best practices rather than accepting them blindly.

Related topics

Transcript Excerpt

There's a misconception about the way you approach optimization. You run a profile, you identify the big parts, you make some changes, you measure statistics. I've worked with many extremely good optimization people and that is not how it is done. >> Assembly language is not all that complicated right? >> All of the JavaScript libraries, the DOM, CSS, React, assembly language, maybe there's 20, 30 instructions you might have to learn total. If you can vertically center a div in HTML, then you can probably learn assembly language, I would say. >> How are you using AI tools, if you're using them at all? >> We are not using them at all. The reason that I want to program things in a game is because I want to program them. If I just wanted an AI to program them, I'd just go get the Unreal [laug…

More from Pragmatic Engineer