Rob Hogan

React Native (mostly Metro) @ Meta

[Nicola Corti @cortinico]

If you're a react-native contributor, please read the following:

Your personal fork of react-native might be locked and could prevent you from contributing further

[Rob Hogan @robjhogan]

@EliotGevers @reactnative 🤐

[Rob Hogan @robjhogan]

@huntie Good God no.

Issues >> DMs

[Nicola Corti @cortinico]

Yesterday we relocated 🎉

[Rob Hogan @robjhogan]

@knotbin @thymikee We thought about it!
1) because react/react exists
2) because repo name == main package name is nice
3) because a git clone would be just be called “native” and that’s weird
4) because changing the org already broke enough stuff 😅

[Rob Hogan @robjhogan]

@jarredsumner Flow? Please be Flow.

[Rob Hogan @robjhogan]

@thymikee @Kelset Optimisations available in 0.84 under `unstable_transformProfile=hermes-stable` for the adventurous - currently that disables transpiling classes, soon it will remove several other unnecessary transforms once we’ve tested them in FB. It’ll be the default for the next release.

[Rob Hogan @robjhogan]

@thymikee @Kelset FWIW - we dropped a bunch of Babel transforms not required even under legacy Hermes in 0.84, but we’re still not fully optimised for Hermes V1. We’ll drop more by default from 0.85.

[Rob Hogan @robjhogan]

@HeadForPoints No mention of BA in the article, but they operate short haul (inc business) from Stansted in the summer, and have shared Escape in previous years.

[Rob Hogan @robjhogan]

@Baconbrix @tmikov @CipolleschiR @cortinico Features should come more quickly now though - there was quite a lot of internal infra to untangle to allow us to roll out use of SH features without breaking legacy Hermes builds. The class transform will be the first next week. More to follow.

[Rob Hogan @robjhogan]

@Baconbrix @tmikov @CipolleschiR @cortinico Module systems are trickier than most language features because obviously they’re heavily linked to resolution + bundling. I don’t think Hermes should internalise RN (or even JS) resolution, but I’d like to see a meeting in the middle with something like the ESM bundle proposal.

[Rob Hogan @robjhogan]

@Baconbrix @tmikov @CipolleschiR @cortinico Features behind a Hermes flag will be the next priority, but as @cortinico says we don’t want to make RN open source users our beta testers ahead of Meta apps. I am keen to make sure OSS gets these features as soon as we’re confident in them.

[Rob Hogan @robjhogan]

@Baconbrix @krystofwoldrich @expo @huntie In principle, yep, but -
- we were keen not to fork implementation / UX / maintenance by platform
- it’s actually a higher value feature on Android due to emulator routing (10.0.2.2 etc)
This particular bug actually looks like Error mangling instead though

[Rob Hogan @robjhogan]

@krystofwoldrich @Baconbrix @expo @huntie Ah good spot, so this looks like a different issue related to mangling of the native Error object, preventing CDT parsing the stack - closely related IIUC: https://t.co/kWNbCgrbwS

We're going to discuss this later today and see if we can move this along

[Rob Hogan @robjhogan]

@Baconbrix @krystofwoldrich @expo @huntie ...for which we have an implementation, but it's disabled due to some perf issues on Android we're working on.

[Rob Hogan @robjhogan]

@Baconbrix @krystofwoldrich @expo @huntie CDT does handle this generally, symbolicating using the source maps it fetches up front. But IIRC it can go wrong when hostnames in stacks (ie device-relative URLs) don't match source URLs in the source maps fetched from the proxy/Metro. loadNetworkResource should fix that...

[Rob Hogan @robjhogan]

@satya164 @hirbod That’d be my suspicion too. Xcode shell steps notoriously find their way around nvm (etc) to old Node versions. Requiring sync ESM graphs should work otherwise.

[Rob Hogan @robjhogan]

@birch_js @Baconbrix @hirbod @expo @inkdrop_app It’s a bit of both - some of the bigger, older apps haven’t been migrated just yet.

[Devon Govett @devongovett]

The most important skill for a software engineer IMO is debugging. Writing code is easy. Willingness and ability to debug through layers of abstraction, through code you didn't write, perhaps deep into other areas of the stack (libraries, frameworks, the server, the browser engine, etc.) can prevent you from ever being "blocked".

This is a skill I see lacking in a majority of developers these days. Too many people just stop as soon as they hit code they didn't write. They just report it to another team, file a GitHub issue, etc. And then complain when it isn't addressed for them immediately.

Your dependencies are your code. You are responsible for them. You can't rely on other people to fix problems you run into all the time. Understand your stack deeply. Learn to debug. It'll help you immensely.