fixed properly

flake.nix

@@ -6,6 +6,10 @@
   outputs = { self, nixpkgs }: let
     system = "x86_64-linux";
     pkgs = import nixpkgs { inherit system; };
+    rust = pkgs.rust-bin.stable.latest.default.override {
+      targets = [ "thumbv8m.main-none-eabihf" ];
+      extensions = [ "rust-src" "rustfmt" "clippy" ];
+    };
   in {
     devShells.${system}.default = pkgs.mkShell {
       packages = with pkgs; [
@@ -34,25 +38,28 @@
       ];
 
       shellHook = ''
-        # Set up Rust target
-        rustup target add thumbv7em-none-eabihf 2>/dev/null || true
+        echo ">>> STM32 DevShell"
 
-        # Ensure probe-rs binary is in PATH
-        if ! command -v probe-rs >/dev/null; then
-          echo "⚠️ probe-rs not found! (check nix installation)"
-        fi
+	export PATH=${pkgs.rust-analyzer}/bin:$PATH
+	export PATH=$HOME/.cargo/bin:$PATH
 
-        export RUST_TARGET=thumbv7em-none-eabihf
+        rustup default stable
+        rustup component add rust-src rustfmt clippy 2>/dev/null || true
+        rustup target add thumbv8m.main-none-eabihf 2>/dev/null || true
+
+        export RUST_TARGET=thumbv8m.main-none-eabihf
         export CARGO_TARGET_DIR=target
+	export DEFMT_LOG=info
         export PATH=$PATH:${pkgs.gcc-arm-embedded}/bin
+        export RUST_SRC_PATH="$(rustc --print sysroot)/lib/rustlib/src/rust/library"
 
 	rustc --version
 	arm-none-eabi-gcc --version | head -n1
         echo "cargo build --release --target thumbv8m.main-none-eabihf"
         echo "cargo flash --release --chip STM32U575ZI"
-	echo "export DEFMT_LOG=info"
 	echo "cargo run --bin main"
 	echo "probe-rs run --chip STM32U575ZITxQ target/thumbv8m.main-none-eabihf/release/main"
+	echo "target/**/build/embassy-stm32-*/out/_generated.rs"
       '';
     };
   };