docs(build): update build instructions (#3641)

docs/build.md

@@ -2,7 +2,8 @@
 
 ## App Build
 
-- Set up your environment [using the react native instructions](https://reactnative.dev/docs/environment-setup).
+- Set up your environment [using the expo instructions](https://docs.expo.dev/guides/local-app-development/).
+  - make sure that the JAVA_HOME points to the zulu-17 directory in your `.zshrc` or `.bashrc` file: `export JAVA_HOME=/Library/Java/JavaVirtualMachines/zulu-17.jdk/Contents/Home`. DO NOT use another JDK or you will encounter build errors.
 - If you're running macOS, make sure you are running the correct versions of Ruby and Cocoapods:
   - Check if you've installed Cocoapods through `homebrew`. If you have, remove it:
     - `brew info cocoapods`
@@ -14,7 +15,7 @@
     - `rbenv global 2.7.6`
     - Add `eval "$(rbenv init - zsh)"` to your `~/.zshrc`
   - From inside the project directory:
-    - `bundler install`
+    - `bundler install` (this will install Cocoapods)
 - Setup your environment [for e2e testing using detox](https://wix.github.io/Detox/docs/introduction/getting-started):
   - `yarn global add detox-cli`
   - `brew tap wix/brew`
@@ -27,7 +28,7 @@
   - `git clone git@github.com:bluesky-social/atproto.git`
   - `cd atproto`
   - `brew install pnpm`
-  - `brew install jq`
+  - optional: `brew install jq`
   - `pnpm i`
   - `pnpm build`
   - Start the docker daemon (on MacOS this entails starting the Docker Desktop app)
@@ -38,11 +39,22 @@
     - Xcode must be installed for this to run.
       - A simulator must be preconfigured in Xcode settings.
         - if no iOS versions are available, install the iOS runtime at `Xcode > Settings > Platforms`.
+        - if the simulator download keeps failing you can download it from the developer website.
+          - [Apple Developer](https://developer.apple.com/download/all/?q=Simulator%20Runtime)
+          - `xcode-select -s /Applications/Xcode.app`
+          - `xcodebuild -runFirstLaunch`
+          - `xcrun simctl runtime add "~/Downloads/iOS_17.4_Simulator_Runtime.dmg"` (adapt the path to the downloaded file)
       - In addition, ensure Xcode Command Line Tools are installed using `xcode-select --install`.
-    - Pods must be installed:
-      - From the project directory root: `cd ios && pod install`.
     - Expo will require you to configure Xcode Signing. Follow the linked instructions. Error messages in Xcode related to the signing process can be safely ignored when installing on the iOS Simulator; Expo merely requires the profile to exist in order to install the app on the Simulator.
+      - Make sure you do have a certificate: open Xcode > Settings > Accounts > (sign-in) > Manage Certificates > + > Apple Development > Done.
+      - If you still encounter issues, try `rm -rf ios` before trying to build again (`yarn ios`)
   - Android: `yarn android`
+    - Install "Android Studio"
+      - Make sure you have the Android SDK installed (Android Studio > Tools > Android SDK).
+        - In "SDK Platforms": "Android x" (where x is Android's current version).
+        - In "SDK Tools": "Android SDK Build-Tools" and "Android Emulator" are required.
+        - Add `export ANDROID_HOME=/Users/<your_username>/Library/Android/sdk` to your `.zshrc` or `.bashrc` (and restart your terminal).
+      - Setup an emulator (Android Studio > Tools > Device Manager).
   - Web: `yarn web`
 - If you are cloning or forking this repo as an open-source developer, please check the tips below as well
 - Run e2e tests