Adds documentation of building and using our dev container.

README.md

@@ -62,9 +62,55 @@ git clone https://git.tomusan.com/your-username/nextcloud-share.git
 cd nextcloud-share
 ```
 
-### 2. Configure Test Environment
+### 2. Build the 3DS Development Container
 
-Copy the example configuration file:
+Build the container image (first time only, or when Dockerfile changes):
+
+```bash
+./scripts/build-container.sh 3ds
+```
+
+This creates a complete 3DS development environment with:
+- devkitARM GCC 15.2.0
+- All 47 available 3DS portlibs
+- CIA creation tools (bannertool, makerom, ctrtool)
+- Build time: ~10-15 minutes on first build
+
+**Note**: The container is built once and reused. You only rebuild when the Dockerfile changes.
+
+### 3. Compile Your 3DS Project
+
+```bash
+# From within your project directory
+cd your-3ds-project
+podman run --rm -v .:/project:z tomusan/devkitarm-3ds:latest make
+
+# Or specify a path
+podman run --rm -v ~/my-game:/project:z tomusan/devkitarm-3ds:latest make
+```
+
+**Output files**: `.3dsx` (homebrew), `.elf` (debug), `.smdh` (metadata), `.cia` (installable)
+
+### 4. Interactive Development Shell
+
+For debugging or manual builds:
+
+```bash
+# Current directory
+./scripts/container-shell.sh
+
+# Specific project
+./scripts/container-shell.sh ~/my-3ds-game
+
+# With extra volumes or environment
+./scripts/container-shell.sh ~/my-game -v /data:/data:z -e DEBUG=1
+```
+
+Inside the container, all devkitARM tools are available in PATH. Run `make` to build, `exit` to leave.
+
+### 5. Configure Test Environment (Optional)
+
+For testing with real Nextcloud servers, copy the example configuration:
 
 ```bash
 cp config.example config
@@ -79,40 +125,37 @@ NEXTCLOUD_USER=your-username
 NEXTCLOUD_PASSWORD=your-password
 ```
 
-**Note**: The `config` file is in `.gitignore` and will never be committed. Each developer should create their own local config.
-
-### 3. Build Using Podman
-
-#### Build the 3DS version:
-
-```bash
-# Build the container image (first time only)
-podman build -f docker/devkitarm.Dockerfile -t nextcloud-share-3ds .
-
-# Compile the project
-podman run --rm -v ./:/project:z nextcloud-share-3ds make -C 3ds
-
-# Output files will be in 3ds/build/
-```
-
-#### Run tests:
-
-```bash
-podman run --rm -v ./:/project:z nextcloud-share-3ds make test
-```
-
-#### Interactive development shell:
-
-```bash
-podman run --rm -it -v ./:/project:z nextcloud-share-3ds bash
-```
+**Note**: The `config` file is in `.gitignore` and will never be committed.
 
 ## 🔧 Building
 
-Detailed build instructions for each platform will be added as they are implemented. See platform-specific README files:
+### Using Development Containers
 
-- [3ds/README.md](3ds/README.md) - Nintendo 3DS build instructions
-- More coming soon...
+All builds run in isolated containers with complete toolchains. See [docker/README.md](docker/README.md) for detailed container documentation.
+
+**Available containers:**
+- **3DS**: `tomusan/devkitarm-3ds:latest` - Nintendo 3DS with full CIA support
+
+**Quick build commands:**
+```bash
+# Build 3DS container (first time)
+./scripts/build-container.sh 3ds
+
+# Compile a 3DS project
+podman run --rm -v ~/my-game:/project:z tomusan/devkitarm-3ds:latest make
+
+# Interactive shell
+./scripts/container-shell.sh ~/my-game
+```
+
+**Build performance:**
+- First build: ~10-15 minutes (downloads and compiles tools)
+- Subsequent builds: Instant (uses build cache)
+- Container rebuilds: Only needed when Dockerfile changes
+
+Platform-specific build instructions:
+- [docker/README.md](docker/README.md) - Container usage and CIA creation
+- More platforms coming soon...
 
 ## ⚙️ Configuration