Really good question as well. Most of the relationship is just that they use the project. Not everyone posts at our users page: babeljs.io/users/.
TL;DR is that they consume it but no one is really helping drive it forward. People will step up in certain areas here and there but ultimately the coordination/vision effort is all on us. It's hard to push things when we are the volunteer led effort though, although I have to be ok with that since it's been that way since the beginning, (Babel is 3 years old: babeljs.io/blog/2017/10/05/babel-t...).
And engineers that work at those companies might know who were are on the team and I might have contact with them from conferences/etc. Most people aren't always asking for feature x/y or even in the issues. They might be one-off DM's on twitter/slack but in the day to day we don't have too much contact with that many companies, and it's really mostly a volunteer thing. No one is really pushing for anything on our roadmap so it's mostly just us trying to figure out what exactly we need for the community (it can be a lot 😂, I really don't know either).
So Adobe: I work at Behance so I have somewhat of a relationship there, I think companies still aren't really putting in the resources there because they might not see the benefits given past history etc. When I gave talks earlier I had a lot of employees tell me they didn't know I worked there (and I mentioned in another thread people think Babel is a Facebook project when it's always been a community project, although Sebastian did work on it at Facebook for sure).
Google: talk to them a lot since although they might use it for their own stuff, they'll use it for OSS projects like github.com/GoogleChrome/workbox, and their users will probably be using Babel. I think browser vendors have a good incentive to make sure Babel is well supported because a lot of the code being sent to the browser is going to be compiled with Babel (so things like code output/speed should be important).
Recently github.com/jridgewell on the AMP team joined as a collaborator team and has been contributing a lot of PRs, and they also donated to the project. Justin has recently joined to represent us at TC39 as well. There's an issue with being an "invited guest" if you don't work at a "TC39" member company so that has honestly been an issue for being able to go.
Facebook: they hired Sebastian to work/make Babel 6, both Yuriy and Amjad made/worked on babel-minify (babili before), and the Flow/React teams help with JSX/Flow PRs sometimes. They recently donated $1k a month to the project which is a nice gesture: twitter.com/left_pad/status/923696... but we still don't have enough for 1 person to be full time atm.
Microsoft/LinkedIn: had some help/contact with the Ember team, like twitter.com/rwjblue, twitter.com/nathanhammond who helped with setting up Babel meetings, and a lot more. We recently collaborated with the TypeScript team to at @babel/preset-typescript after making sure they would help with the PRs and helping keep them in sync (we try to do the same with Flow).
There's a lot of other companies like Airbnb, Netflix, etc too.
Point is that I can recall times we might of talked and stuff but don't really have any sort of regular communication with that many folks or do calls/meetings.
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