how Andarist time-travel debugs the TypeScript compiler with Replay
Andarist loves fixing bugs - that's how he became a maintainer of several popular JS OSS projects and a contributor to the TypeScript compiler. In this video we look at how he uses Replay to debug the TypeScript compiler while he's doing all his cutting-edge advanced TypeScript work.
note: This is (sortof) part 2 of a video with Mark (Erikson, of Replay.io) and Andarist. In Part 1 ( • the time-traveling debugger from the ... ) we got a quick overview of what Replay is and how it works.
https://replay.io
00:00 in this episode
04:35 the idea to use Replay with the TypeScript playground
06:05 thousands of Replay recordings
10:06 committing a change to TypeScript for Replay
11:30 starting the first recording
13:16 on handling displayment for massive files
15:42 looking at a previous recording
18:02 debugging
21:19 the risk presented by side effects
24:04 Replay knows everything from all time
25:19 how it all works up in the cloud
27:27 the caching layer has a memory!
29:45 filtering by your test run
33:18 on putting breakpoints in TypeScript types
35:56 on rewriting the TypeScript compiler in Rust
39:31 use case: using two Replay recordings side-by-side
40:40 there's a lot more Replay can do in the future
43:00 what's the coolest thing you've found in the TypeScript codebase?
46:01 applying learnings to XState
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Andarist loves fixing bugs - that's how he became a maintainer of several popular JS OSS projects and a contributor to TypeScript.
https://github.com/Andarist
/ andaristrake
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