Refactor README and flake.nix for improved development environment setup; remove embedded Rust tooling references and add Cargo productivity tools

.flatpak-builder/ccache/disabled/ccache.conf

@@ -0,0 +1 @@
+disable = true

README.md

@@ -15,8 +15,6 @@ direnv allow
 When you enter the devShell (via `direnv allow` or `nix develop`), the following happens automatically:
 
 ✓ **Git Repository**: Initializes `.git` if not present
-✓ **Rust Targets**: Automatically adds common embedded Rust targets (ARM Cortex-M, RISC-V)
-✓ **Cargo Paths**: Sets up `$HOME/.cargo/bin` in PATH for cargo-installed binaries
 ✓ **Welcome Banner**: Displays available tools and quick commands
 
 No manual setup needed! Just start coding.
@@ -24,32 +22,17 @@ No manual setup needed! Just start coding.
 ## Quickstart
 
 ```sh
-nix flake init -t path:../flakes#rust
 nix develop
 cargo build
 ```
 
-## Embedded Rust Support
-
-The devShell automatically installs common embedded Rust targets via `rustup`:
-
-| Target | Platform | Use Case |
-|--------|----------|----------|
-| `thumbv6m-none-eabi` | ARM Cortex-M0/M0+ | RP2040 (Pico) |
-| `thumbv7em-none-eabihf` | ARM Cortex-M4F/M7F | STM32, nRF52840 |
-| `riscv32imc-unknown-none-elf` | RISC-V 32-bit | ESP32-C3 (basic) |
-| `riscv32imac-unknown-none-elf` | RISC-V 32-bit (atomic) | ESP32-C3 (advanced) |
-
-**Note:** ESP32 Xtensa targets require espup or custom toolchains (see [esp-rs](https://github.com/esp-rs)).
-
 ## Flatpak Packaging
 
 This project supports building Flatpak packages for the FeDIY application.
 
 ### Build Flatpak Package
 
-1. Ensure you have `flatpak-builder` installed.
+1. Run:
-2. Run:
 
   ```bash
   make flatpak-build
@@ -80,14 +63,11 @@ flatpak run com.moturpin.fediy
 | **rustfmt** | Rust code formatter |
 | **rust-analyzer** | Language server for IDE integration |
 | **rust-src** | Rust source code (for tools like rust-analyzer) |
-| **probe-rs** | Embedded debugger/flasher for ARM targets |
+| **cargo-deny** | Audit dependencies for advisories and license policy |
-| **espflash** | Flashing tool for ESP32 boards |
+| **cargo-edit** | Add/remove/upgrade Cargo dependencies from the CLI |
-| **openocd** | JTAG/SWD debugger for ARM and other targets |
+| **cargo-watch** | Auto-rebuild on file changes |
-| **minicom** | Serial terminal for device output |
+| **flatpak-builder** | Build Flatpak distribution packages |
-| **elf2uf2-rs** | Convert ELF to UF2 format (RP2040) |
+| **pre-commit** | Run pre-commit hooks |
-| **picotool** | Pico-specific firmware operations |
-| **avrdude** | AVR microcontroller programmer |
-| **ravedude** | Rapid AVR development utility |
 
 ## Testing & Development Features
 
@@ -109,8 +89,11 @@ cargo clippy
 # Format code
 cargo fmt
 
-# Build for embedded target
+# Watch and rebuild on changes
-cargo build --target thumbv7em-none-eabihf --release
+cargo watch -x build
+
+# Build a Flatpak
+make flatpak-build
 ```
 
 ## Project Layout

flake.nix

@@ -60,30 +60,22 @@
         {
           default = pkgs.mkShell {
             packages = with pkgs; [
+              # Rust toolchain (managed by fenix overlay)
               rustToolchain
+              rust-analyzer
+              # Build essentials
               git
               gnumake
               openssl
               pkg-config
+              # Cargo productivity tools
               cargo-deny
               cargo-edit
               cargo-watch
-              cargo-generate
+              # Code quality
-              rust-analyzer
-              rustup
-              # Embedded Rust tooling
-              probe-rs-tools
-              espflash
-              openocd
-              minicom
-              # RP2040 UF2 workflows
-              elf2uf2-rs
-              picotool
-              avrdude
-              pkgsCross.avr.buildPackages.libc
-              pkgsCross.avr.buildPackages.gcc
-              ravedude
               pre-commit
+              # Packaging
+              flatpak-builder
             ];
 
             env = {
@@ -98,20 +90,9 @@
                 echo "✓ Initialized git repository"
               fi
 
-              # Ensure user's Cargo-installed binaries are available
+              echo "[FeDIY] Welcome to the dev shell!"
-              export PATH="$HOME/.cargo/bin:$PATH"
+              echo "Tools: cargo, rustc, clippy, rustfmt, rust-analyzer, flatpak-builder"
-
+              echo "Run 'cargo build' to build, 'make flatpak-build' for Flatpak, or 'nix run .#dev-helper' for a tool summary."
-              if command -v rustup >/dev/null 2>&1; then
-                echo "Ensuring common embedded Rust targets are available (idempotent)..."
-                rustup target add thumbv6m-none-eabi       >/dev/null 2>&1 || true  # Cortex-M0/M0+ (RP2040)
-                rustup target add thumbv7em-none-eabihf    >/dev/null 2>&1 || true  # Cortex-M4F/M7F (many STM32/nRF52)
-                rustup target add riscv32imc-unknown-none-elf >/dev/null 2>&1 || true
-                rustup target add riscv32imac-unknown-none-elf >/dev/null 2>&1 || true  # ESP32-C3 class
-                echo "Note: ESP32 Xtensa targets require espup/custom toolchains (see esp-rs)."
-              fi
-              echo "[FeDIY] Welcome to the Rust dev shell!"
-              echo "Tools: cargo, rustc, clippy, rustfmt, rust-analyzer, probe-rs, espflash, openocd, minicom, elf2uf2-rs, picotool, avrdude, ravedude"
-              echo "Run 'cargo build' to build, or 'nix run .#dev-helper' for a tool summary."
               echo "See README.md for usage."
             '';
           };
@@ -130,10 +111,12 @@
           };
 
           devHelper = pkgs.writeShellScriptBin "dev-helper" ''
-            echo "Rust toolchain available:"
+            echo "=== FeDIY dev shell tools ==="
-            command -v cargo >/dev/null 2>&1 && cargo --version || true
+            command -v cargo >/dev/null 2>&1 && echo "cargo: $(cargo --version)" || echo "cargo: not found"
-            command -v rustc >/dev/null 2>&1 && rustc --version || true
+            command -v rustc >/dev/null 2>&1 && echo "rustc: $(rustc --version)" || echo "rustc: not found"
-            echo "This binary is built by Nix (packages.default)."
+            command -v rust-analyzer >/dev/null 2>&1 && echo "rust-analyzer: $(rust-analyzer --version)" || echo "rust-analyzer: not found"
+            command -v flatpak-builder >/dev/null 2>&1 && echo "flatpak-builder: $(flatpak-builder --version)" || echo "flatpak-builder: not found"
+            command -v pre-commit >/dev/null 2>&1 && echo "pre-commit: $(pre-commit --version)" || echo "pre-commit: not found"
           '';
         }
       );