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CONTRIBUTING.md

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 # Contributing to Finamp
 
+Thanks for your interest in contrtributing to Finamp! This document goes over how to get started on Finamp development, and other ways to contribute.
+
+## Setting up a Development Environment
+
+Finamp is a fairly standard Flutter app, so all you have to do is [install Flutter](https://docs.flutter.dev/get-started/install). Once Flutter is installed, you should be able to run Finamp on emulators/real devices.
+
+### Android Keys
+
+To build release APKs, you need to set up a signing key for Android. To get that set up, follow [this guide](https://docs.flutter.dev/deployment/android#signing-the-app) from the Flutter documentation. Note that if you have Finamp installed already, your phone may panic because the key is different.
+
+### The Arcane Arts (Code Generation)
+
+![A conversation between me and Chaphasilor. I say "did you try running (the Dart build command)?" They reply "I wasn't aware I need to use the arcane arts for this"](assets/arcane-arts.png)
+
+Because Dart doesn't support macros and stuff, a few dependencies rely on code generation which must be run manually. These dependencies are:
+
+* Hive - the database that Finamp uses for storing all data
+* `json_serializable` - For deserialising JSON into classes
+
+To rebuild these files, run `dart run build_runner build --delete-conflicting-outputs`. This must be done when:
+
+* Modifying a class that is returned by Jellyfin (such as the classes in `lib/models/jellyfin_models.dart`)
+* Adding fields to a database class (annotated with `@HiveType`)
+
+### Hive
+
+As said earlier, Finamp uses Hive for all data storage needs. If you're doing work that involves data storage, I recommend you read [the Hive docs](https://docs.hivedb.dev/#/). Please ensure that your changes work when upgrading Finamp from the current release to your changes, as not handling upgrades will cause the app to crash.