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ivarvongon Low-cost open source device can measure air pollution anywhere

There's a mention of the SEN5X here: https://github.com/MIT-Senseable-City-Lab/OSCS/blob/main/Bui...

ivarvongon Two years of Elixir at the Outline

I evaluated a few things at the beginning. I was previously using Ruby/Rails and Node.js, and Rails was my go-to for full-stack webdev.

There was some interest in building a headless WordPress site, but the limitations on database design and performance led me back to a monolith. I have a general preference for monoliths when time is tight (time is always tight) -- the things you get for free are very helpful: deploy/rollback, DB migrations, API versioning, local dev workflow, CI, among others.

I'd deployed a couple small Elixir apps at my previous job, as well as some toy projects in Elixir/Phoenix. I've played with JVM languages like Scala and Clojure, I've tried to learn Haskell about five times. Elixir had a great developer experience story (a couple people can build a nontrivial app in ~weeks). It's on par with Ruby/Rails. We went all-in around September 2016, launching in early December of 2016.

Edit: I should have mentioned, I'm the CTO of The Outline.

ivarvongon Two years of Elixir at the Outline

Dave and I started building this app together two years ago -- we both came from different ecosystems (Dave from Node, me from Rails). It's been incredibly rewarding for us to be on Elixir/Phoenix.

There's so much more to say about why Elixir is a great choice for webdev (I love Rails but probably wouldn't go back). This post gets to some of the high-level stuff we've learned -- happy to answer any questions folks have!

ivarvongon Languages on BEAM, the Erlang virtual machine

We have Elixir/Phoenix in production on Heroku (with Heroku Pipelines) using a custom buildpack [0]. It's been great. We'll probably look at Docker. We use CircleCI, and this setup script [1] was a great starting point.

0: https://github.com/HashNuke/heroku-buildpack-elixir 1: https://gist.github.com/joakimk/48ed80f1a7adb5f5ea27

ivarvongon SpaceX Grasshopper 744m test flight [video]

UHF transmitters can be rigged on a RC transmitter as a module or through the trainer port, depending on the radio. DragonLink and EZUHF appear to work this way. (I haven't used any of these.)

ivarvongon SpaceX Grasshopper 744m test flight [video]

I think this was shot with a DJI S800. The RC link to fly it is usually 2.4GHz. A separate link, often at 5.8GHz, is used to send the camera feed back to the ground to help the pilot or compose the shot, or both.

ivarvongon NeDB, a pure Javascript database for Node.js and Node Webkit

It might be interesting to persist snapshots to S3. It might be usable for small projects on Heroku/etc with ephemeral storage. It could be patched here (?) [1], but clearly there'd be a lot of issues with the long network call, how often to do it, how durable it really is, etc.

1: https://github.com/louischatriot/nedb/blob/b1abd34384cefea16...