Added:

- `build.kind = "efi"` — UEFI PE32+ executable support. Links with `-shared -nostdlib -Wl,-dll -Wl,--subsystem,10`, output via `efi_path()` with `.efi` extension, rejected by `dcr run`.
- `build.kind = "elf"` — bare-metal ELF executable support. Uses `elf_path()` output path, rejected by `dcr run`, no extra linker flags.

Fixed:

- `dcr run` with `--target` or `build.target` now correctly finds the binary in the arch-specific target directory.
- `dcr run` checks profile-specific `build.{profile}.kind` before rejecting library builds (previously only checked `build.kind`).
- `dcr clean` now reads `build.target` from `dcr.toml` when no `--target` flag is given.
- Linux: target directory is now consistent — `target/<arch>-unknown-linux-gnu/<profile>/` (no stale `target/<profile>/`).
- `dcr.lock` is now populated with all resolved dependencies (registry, path, git) instead of being always empty.
- Git dependencies are now properly recognized and recorded in `dcr.lock`.
- `is_registry_dep` correctly identifies version-based registry dependency tables (`{ version = "..." }`) and rejects tables with unknown keys.
- `dcr test` accepts `--debug`/`--release` flags (defaults to `debug` profile instead of always `release`).
- Build fingerprint cache (`build_cache_path`) now includes `target_dir` — different targets no longer share a single cache entry.
- `object_path` no longer hardcodes the `src/` prefix — works correctly with custom `build.roots` (e.g. `roots = ["lib"]`).
- `dcr update` now generates `.exe` candidates for all Windows targets, not just `x86_64-pc-windows-msvc`.
- Compiler existence is verified before starting the build (clear error if compiler is not found in PATH).
- Consolidated duplicate `OUTPUT_MUTEX` definitions — MSVC backend now uses the shared mutex from `common.rs`.
- Registry cache root directory is created if missing (prevents cryptic errors when `~/.dcr/` does not exist).

src/platform/macos.rs

@@ -12,6 +12,20 @@ pub fn lib_path(profile: &str, name: &str, target_dir: Option<&str>) -> String {
     }
 }
 
+pub fn elf_path(profile: &str, name: &str, target_dir: Option<&str>) -> String {
+    match target_dir {
+        Some(dir) => format!("{}/{}", dir.trim_end_matches('/'), name),
+        None => format!("./target/{profile}/{name}"),
+    }
+}
+
+pub fn efi_path(profile: &str, name: &str, target_dir: Option<&str>) -> String {
+    match target_dir {
+        Some(dir) => format!("{}/{}.efi", dir.trim_end_matches('/'), name),
+        None => format!("./target/{profile}/{name}.efi"),
+    }
+}
+
 pub fn shared_lib_path(profile: &str, name: &str, target_dir: Option<&str>) -> String {
     match target_dir {
         Some(dir) => format!("{}/lib{}.dylib", dir.trim_end_matches('/'), name),