91–100 of 112 posts
also, accessibility tools. largely pragmatic, since my limbs are slowly betraying me, but I genuinely enjoy the bootstrapping aspect, and the empowerment.
Lately I've been playing around with learning type theory and writing parsers and langauges. But I seem to gravitate towards writing code to decode various file formats. Over the years I've reverse engineered Apple Notes database, written code to read the realm database backing Craft.app, code to read couchdb files, lucene files, git pack files, sqlite databases (I have js code that runs queries against raw database…
Not my area at all, but reverse-engineering file formats sounds really interesting. Do you have a blog by any chance?
I do have some brief notes on the "Notes.app" format here:
https://github.com/dunhamsteve/notesutils/blob/master/notes....
But I didn't discuss my methodology -- Generic decoding of protobuf, building up a schema as you go -- the tricky part there is that a byte array and a substructure look the same, so you have to try to decode it, and if successful, try that schema on the next example.
Here is another fun technique - scanning through a disassembly of an Apple framework looking for assembly patterns that match the protobuf compiler output (this was dependent on which language was targeted by protobuf):
https://gist.github.com/dunhamsteve/224e26a7f56689c33cea4f0f...
So you find the serializer / deserializer code and figure out what the original protbuf spec looked like.
Earlier quoted context omitted.
Not my area at all, but reverse-engineering file formats sounds really interesting. Do you have a blog by any chance?
I should write this stuff up, but I haven't. I do have some brief notes on the "Notes.app" format here: https://github.com/dunhamsteve/notesutils/blob/master/notes.... But I didn't discuss my methodology -- Generic decoding of protobuf, building up a schema as you go -- the tricky part there is that a byte array and a substructure look the same, so you have to try to decode it, and if successful, try that schema on t…
SQLite got me a little experience with b-trees (as did couch), and I got to write a little query planner.
Lucene was interesting because it was compact, had some skip lists for fast lookup, and was a log-structured merge tree. I borrowed bits of it for an index in a binary file format for work.
For realmdb / couchdb, I looked at the source code.
I did realm so I could extract my Craft.app docs. It's interesting because it's a column structured database, so I got to learn a little bit about that. I also learned that C++ had changed a bit since I last used it (lambdas!).
And couch is an append-only btree. I got to learn to read Erlang with that project.
I've also have a web scraper that reads from the Chrome cache (whose format keeps changing). I archive things like recipes that show up in the cache.
And I've got code on github that decodes iOS desktop backups, which some people have found useful. (Written mainly so I could poke around in various applications' data and extract stuff from my keychain.)
Earlier quoted context omitted.
I worked in a construction company where we drawed blueprints in AutoCAD for these pen plotters. It was very soothing to see them work, but we had this pervert engineer who would caress the long brush's hairs under them and whisper sexy things. Unfortunately, that is irremediably linked in my mind to pen plotters.
I want to buy that robosexual colleague of yours a beer. Maybe he could seduce my apartment's AC into actually working in the summer?
Gotcha!
some have really interesting approaches on storing different types of data.
Embedded systems with Elixir/Nerves. Fun to work with and the business opportunities are endless. My current startup measures the content of water in storage tanks with a realtime dashboard for vineyards.
How would you recommend getting started?
Whenever I get bored (rarely these days) I like to write path-finding & annealing algorithms. I start with a super simple ray-tracing framework I first wrote in the 1990's for visualization, and then I play around with things like gravity and electromagnetic repulsion / attraction. My favorite thing to do is watch a million charged spheres distribute themselves on a weird surface obeying gravity and electromagnetics,…