added documentation

Author: CD-Z

CONTRIBUTING-NIX.md

@@ -0,0 +1,103 @@
+# React Native Development Nix Environment Setup
+
+This document outlines how to set up your React Native development environment using Nix flakes for reproducibility and isolation.
+
+## Disclaimer
+
+This was tested on an Arch Linux system with AMD CPU and GPU. There are likely problems with NVIDIA GPUs.
+
+Compatibility with Microsoft WSL2 is not guaranteed, but should work withoud major issues, except for the emulator.
+
+## Prerequisites
+
+*   **Nix installed**: [https://nixos.org/download.html](https://nixos.org/download.html)
+*   **Git**: Required for cloning the repository.
+*   **KVM (for emulator, if enabled)**: Ensure KVM is enabled and your user is in the `kvm` group for optimal emulator performance:
+    ```bash
+    sudo usermod -aG kvm $USER && newgrp kvm # (or log out/in)
+    kvm-ok # Verify KVM acceleration
+    ```
+*   **GPU Drivers (for emulator, if enabled)**: For hardware-accelerated emulator (AMD/Intel), ensure host Vulkan drivers are working:
+    ```bash
+    vulkaninfo | grep -i "device name" # Should show your GPU
+    ```
+    If not, install `vulkan-radeon` (AMD) or `vulkan-intel` (Intel) on your host system and reboot.
+
+
+## Getting Started
+
+1.  **Clone the Project:**
+    ```bash
+    git clone <your-fork-url>
+    cd <your-fork-name>
+    ```
+
+2.  **Enter the Development Shell:**
+
+    If you have `npm` or `yarn` installed, use the defined scripts:
+    *   **For Physical Device Only (default):**
+        ```bash
+        npm run nix # or yarn nix
+        ```
+    *   **For Emulator Development (explicitly enable):**
+        ```bash
+        npm run nix-emulator # or yarn nix-emulator
+        ```
+
+    If you do not have `npm`/`yarn` installed, execute the commands manually:
+    *   **For Physical Device Only (default):**
+        ```bash
+        nix develop --extra-experimental-features nix-command --extra-experimental-features flakes
+        ```
+    *   **For Emulator Development (explicitly enable):**
+        ```
+        nix develop .#emulator --extra-experimental-features nix-command --extra-experimental-features flakes
+        ```
+
+    The first time, this will download and set up all required tools, which can take considerable time. Subsequent entries will be much faster. You will also see a message about "Setting up writable Android SDK..." which only happens once.
+
+## Development Workflow
+
+Once inside the `nix develop` shell, all tools are available.
+
+### 1. Start Metro Bundler
+
+Open a new terminal or run in the background:
+```bash
+npm start
+```
+
+### 2. Physical Device Development
+
+1.  **Connect Device**: Enable USB debugging on your Android device and connect it via USB.
+2.  **Verify Device**:
+    ```bash
+    adb devices
+    ```
+3.  **Mirror Screen (Optional)**:
+    ```bash
+    scrcpy # Mirrors screen, provides control
+    scrcpy -s <device_serial> # If multiple devices connected
+    ```
+4.  **Run App**:
+    ```bash
+    npx run android
+    ```
+
+### 3. Android Emulator Development (if enabled)
+
+1.  **Launch Emulator**:
+    ```bash
+    emulator -avd ReactNative_API35 -gpu host -no-metrics -no-audio
+    ```
+    *   Use `-gpu swiftshader_indirect` if hardware acceleration (`-gpu host`) fails.
+
+2.  **Verify Emulator**:
+    ```bash
+    adb devices
+    ```
+3.  **Run App**:
+    Launches the the emulater automatically, if it is not already running.
+    ```bash
+    npx run android
+    ```

package.json

@@ -14,7 +14,9 @@
     "open": "open ./android/app/build/outputs/apk/release/",
     "strings": "node scripts/stringTypes.cjs",
     "prepare": "husky install",
-    "rebuild": "rm -rf node_modules/ ./android/build/ ./android/app/build/ ./android/app/.cxx && npm i && cd android/ && ./gradlew clean && cd .. && npm start -- --reset-cache"
+    "rebuild": "rm -rf node_modules/ ./android/build/ ./android/app/build/ ./android/app/.cxx && npm i && cd android/ && ./gradlew clean && cd .. && npm start -- --reset-cache",
+    "nix": "nix develop --extra-experimental-features nix-command --extra-experimental-features flakes",
+    "nix-emulator": "nix develop .#emulator --extra-experimental-features nix-command --extra-experimental-features flakes"
   },
   "codegenConfig": {
     "name": "LNReaderSpec",