test: normalize git dependency paths on Windows

.gitignore

@@ -9,3 +9,4 @@ personal/
 .*
 !.gitignore
 !.github/
+graphify-out/

CHANGELOG.md

@@ -1,6 +1,6 @@
 # Changelog
 
-## [Unreleased]
+## [v0.9.0] - 2026-08-31 "Полные Path/Git-зависимости и готовые библиотеки / Complete Path/Git Dependencies & Prebuilt Libraries"
 
 ### RU
 
@@ -8,6 +8,10 @@
 
 - **Зеркала загрузок в `dcrup`** — `--mirror auto|cf|gh|sf|ya` и `DCRUP_MIRROR`.
   По умолчанию `auto`: **cf → gh → sf → ya** (CloudFlare CDN, GitHub, SourceForge, Yandex CDN).
+- **Полные Path/Git-зависимости** — DCR-пакеты из `path` и `git` собираются перед потребителем; Git-код кешируется в `~/.dcr/git`, поддерживает `branch`/`tag`/`rev` и фиксирует точный commit в `dcr.lock`.
+- **Транзитивные зависимости и защита от циклов** — DCR рекурсивно собирает DCR-пакеты и показывает цепочку циклической зависимости.
+- **Внешние готовые библиотеки через path/Git** — `include`, `lib` и `libs` подключают библиотеку без `dcr.toml`; Git prebuilt-источники тоже фиксируются по точному commit.
+- **Явный режим зависимости** — `mode = "build"` и `mode = "prebuild"` позволяют выбрать сборку DCR-пакета или подключение готовых артефактов, даже когда репозиторий содержит оба варианта.
 
 **Удалено:**
 
@@ -19,6 +23,10 @@
 
 - **Download mirrors in `dcrup`** — `--mirror auto|cf|gh|sf|ya` and `DCRUP_MIRROR`.
   Default `auto` tries **cf → gh → sf → ya** (CloudFlare CDN, GitHub, SourceForge, Yandex CDN).
+- **Complete Path/Git dependencies** — DCR packages from `path` and `git` are built before their consumer; Git sources are cached in `~/.dcr/git`, support `branch`/`tag`/`rev`, and lock the exact commit in `dcr.lock`.
+- **Transitive dependencies and cycle protection** — DCR recursively builds DCR packages and reports the dependency cycle chain.
+- **Prebuilt external libraries through path/Git** — `include`, `lib`, and `libs` link libraries without `dcr.toml`; Git prebuilt sources are locked to their exact commit as well.
+- **Explicit dependency mode** — `mode = "build"` and `mode = "prebuild"` select DCR package builds or ready-made artifacts when a repository contains both forms.
 
 **Removed:**
 

Cargo.lock

@@ -154,7 +154,7 @@ dependencies = [
 
 [[package]]
 name = "dcr"
-version = "0.8.5"
+version = "0.9.0"
 dependencies = [
  "ctrlc",
  "fatfs",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "dcr"
-version = "0.8.5"
+version = "0.9.0"
 edition = "2024"
 build = "build.rs"
 description = "DCR is a utility for managing C/C++ projects in a Cargo-like style."
@@ -89,3 +89,12 @@ lto = false
 codegen-units = 16
 panic = "abort"
 strip = true
+
+[profile.dev]
+incremental = false
+opt-level = 0
+debug = "line-tables-only"
+
+[profile.dev.package."*"]
+opt-level = 1
+debug = false

README.md

@@ -39,7 +39,10 @@
 
 ```sh
 yay -S dcr
+# or
+paru -S dcr
 ```
+> 💡 Do you like DCR? Vote for the package on the [AUR](https://aur.archlinux.org/packages/dcr) page—it will help the project get into the official "extra" repository!
 
 </td>
 </tr>

docs/changelog.mdx

@@ -4,10 +4,15 @@ sidebar_label: Changelog
 
 # Changelog
 
-## Unreleased
+## 0.9.0 (2026-08-31) 
 
 - **Download mirrors in `dcrup`** — `--mirror auto|cf|gh|sf|ya` and `DCRUP_MIRROR`.
   Default `auto` tries **cf → gh → sf → ya** (CloudFlare CDN, GitHub, SourceForge, Yandex CDN).
+- **Complete Path/Git dependencies** — DCR packages from `path` and `git` are built before their consumer. Git sources are cached in `~/.dcr/git`, support `branch`/`tag`/`rev`, and record the exact commit in `dcr.lock`.
+- **Build and prebuild modes** — `path` and `git` dependencies can build a DCR package from `dcr.toml` or link existing `include`/`lib`/`libs` artifacts; `mode = "build"` / `"prebuild"` selects explicitly when both forms are present.
+- **Prebuilt dependency examples** — documentation now shows the `dcr-math-lib` Git repository and recommended build/prebuilt layouts for both `git` and `path`.
+- **Transitive dependency builds and cycle reporting** — DCR recursively builds DCR packages and reports a clear dependency chain for cycles.
+- **Bare path arguments for `dcr add`** — `dcr add mylib ../mylib` now works in addition to the explicit `path:` form.
 - **Removed `install.sh` / `install.ps1` / `install_bsd.sh`** — superseded by `dcrup`.
 
 ## 0.8.5 (2026-08-08)

docs/commands/dependency-commands.mdx

@@ -29,7 +29,7 @@ Flags:
 - `--tag <name>` — git tag
 - `--rev <hash>` — git commit
 
-If source is omitted — DCR searches connected registries.
+If source is omitted — DCR searches connected registries. A bare relative or absolute path is accepted as a path dependency.
 
 ## `dcr tree`
 

docs/reference/dependencies.mdx

@@ -23,10 +23,10 @@ The version string is used as-is for registry lookup.
 
 ```toml
 [dependencies]
-fmt = { git = "https://github.com/fmtlib/fmt", tag = "10.1.1" }
+dcr-math = { git = "https://github.com/dexoron/dcr-math-lib.git", tag = "v0.1.0" }
 ```
 
-Fields: `git`, `branch`, `tag`, `rev`.
+Fields: `git`, `branch`, `tag`, `rev`, `mode`, `include`, `lib`, `libs`.
 
 ### Table (path)
 
@@ -35,6 +35,15 @@ Fields: `git`, `branch`, `tag`, `rev`.
 mylib = { path = "../mylib" }
 ```
 
+For a prebuilt external library, specify its layout explicitly. The three
+arrays are paths relative to the dependency root (`include`, `lib`) and linker
+names (`libs`):
+
+```toml
+[dependencies]
+dcr-math = { path = "../deps/dcr-math", include = ["include"], lib = ["lib"], libs = ["dcr-math"] }
+```
+
 ## Registry
 
 DCR uses a package registry for dependency lookup by name.
@@ -42,7 +51,7 @@ DCR uses a package registry for dependency lookup by name.
 ```toml
 # ~/.dcr/config.toml
 [registry.default]
-url = "https://index.dcr.pm"
+url = "https://index.dcr.dexoron.tech"
 priority = 1
 ```
 
@@ -50,7 +59,23 @@ Registry priority: order in `config.toml`. The `DCR_INDEX_PATH` variable overrid
 
 ## Git dependencies
 
-Git dependencies are parsed and recorded in `dcr.lock`. DCR supports specifying branch/tag/rev for git sources:
+Git dependencies are cloned into `~/.dcr/git/`; their exact checked-out commit is written to `dcr.lock`.
+
+Both Git and path dependencies have two modes:
+
+- **DCR package:** the source has `dcr.toml`. DCR builds it before the consumer and uses the package name from its manifest for linking.
+- **Prebuilt library:** it provides existing headers and binaries through `include`, `lib`, and `libs`. DCR passes them to the compiler/linker without building the dependency.
+
+The mode is normally detected automatically. Use `mode = "build"` or `mode = "prebuild"` when a source contains both a manifest and prebuilt artifacts and you need to choose explicitly.
+
+`dcr-math-lib` publishes both forms. Select its prebuilt library explicitly:
+
+```toml
+[dependencies]
+dcr-math = { git = "https://github.com/dexoron/dcr-math-lib.git", tag = "v0.1.0", mode = "prebuild", include = ["include"], lib = ["lib"], libs = ["dcr-math"] }
+```
+
+DCR supports specifying branch/tag/rev for git sources:
 
 - `branch` — switch to a branch
 - `tag` — switch to a tag
@@ -59,7 +84,7 @@ Git dependencies are parsed and recorded in `dcr.lock`. DCR supports specifying
 
 ## Path dependencies
 
-Local paths. DCR automatically discovers include and lib directories from the neighbor's `dcr.toml`.
+Local paths may point at a DCR package or a prebuilt external library. A path DCR package is built before its consumer, including its own path/git dependencies. DCR detects dependency cycles. A prebuilt library is never built by DCR; it is linked from the directories declared in its dependency entry.
 
 ```toml
 [dependencies]
@@ -67,18 +92,51 @@ mylib = { path = "/abs/path/to/lib" }
 mylib = { path = "../relative/path" }
 ```
 
-*Note: Header resolution automatically checks the packaged `target/include` directory of path dependencies, ensuring consumer packages can find headers from compiled static or dynamic libraries.*
+For DCR packages, the package name from `dcr.toml` is used for linking (so the dependency key may differ from the library name). Header resolution includes the packaged `target/include` directory and link search includes `target/lib`.
+
+### Recommended library layouts
+
+Buildable DCR library:
+
+```text
+dcr-math-lib/
+├── dcr.toml
+└── src/
+    ├── dcr_math.c
+    └── dcr_math.h
+```
+
+Prebuilt library:
+
+```text
+dcr-math-lib/
+├── include/
+│   └── dcr_math.h
+└── lib/
+    └── libdcr-math.a       # or .so / .lib
+```
+
+`libs` contains linker names without the `lib` prefix and file extension: use
+`["dcr-math"]` for `libdcr-math.a`.
+
+If one repository contains both forms, keep the prebuilt files in `include/` and `lib/` and select the mode explicitly:
+
+```toml
+[dependencies]
+dcr-math = { git = "https://github.com/dexoron/dcr-math-lib.git", tag = "v0.1.0", mode = "prebuild", include = ["include"], lib = ["lib"], libs = ["dcr-math"] }
+```
+
+For a local copy, replace `git` with `path = "../dcr-math-lib"`. In `prebuild` mode DCR does not run the dependency build, even when `dcr.toml` is present.
 
 ## dcr.lock
 
 Dependency lock file. Contains package names and sources.
 
-Created during `dcr build` when registry dependencies are present. Not updated during `dcr add` — only on the next `dcr build`.
+Created during `dcr build` for resolved registry, path, and Git dependencies. Not updated during `dcr add` — only on the next `dcr build`.
 
 ## Resolution process
 
-1. Load all dependencies (registry → git → path)
-2. For path deps: recursively read their `dcr.toml`
-3. For registry deps: search `index.json`
-4. For git deps: clone to cache
-5. Collect `include_dirs`, `lib_dirs`, `libs` for the compiler
+1. Resolve dependency sources (registry → git → path)
+2. Fetch git dependencies into `~/.dcr/git/` and check out the requested ref
+3. Build DCR package dependencies recursively
+4. Collect `include_dirs`, `lib_dirs`, `libs` for the compiler

src/cli/add.rs

@@ -288,8 +288,15 @@ fn parse_add_args(args: &[String]) -> Result<AddArgs, i32> {
         || source_spec.starts_with("git@")
     {
         git = Some(source_spec);
+    } else if source_spec.starts_with("./")
+        || source_spec.starts_with("../")
+        || std::path::Path::new(&source_spec).is_absolute()
+    {
+        path = Some(source_spec);
     } else {
-        error("Source must have a prefix (path:, git:, github:, gitlab:) or be a full URL");
+        error(
+            "Source must be a path, a prefixed source (path:, git:, github:, gitlab:), or a full URL",
+        );
         return Err(1);
     }
 

src/core/build/engine.rs

@@ -35,7 +35,7 @@ use crate::core::build::steps::{
     get_build_steps_with_profile, run_build_steps, verify_expectations,
 };
 use crate::core::build_config::Config;
-use crate::core::deps::{register, resolve_deps};
+use crate::core::deps::resolve_deps;
 use crate::core::workspace::parse_workspace;
 use crate::utils::build::{
     default_target_triple, get_bool_with_profile, get_config_opt, get_config_str,
@@ -335,6 +335,81 @@ fn build_project_at(
     workspace_root: Option<&Path>,
     cancel: &Arc<AtomicBool>,
     rep: &mut dyn BuildReporter,
+) -> Result<(), String> {
+    let mut dependency_stack = Vec::new();
+    build_project_at_with_stack(
+        project_root,
+        profile,
+        target,
+        explicit_target,
+        exclude_dirs,
+        force,
+        verbose,
+        workspace_root,
+        cancel,
+        rep,
+        &mut dependency_stack,
+    )
+}
+
+/// Builds a package while tracking the dependency chain to reject cycles.
+#[allow(clippy::too_many_arguments)]
+fn build_project_at_with_stack(
+    project_root: &Path,
+    profile: &str,
+    target: Option<&str>,
+    explicit_target: bool,
+    exclude_dirs: &[std::path::PathBuf],
+    force: bool,
+    verbose: bool,
+    workspace_root: Option<&Path>,
+    cancel: &Arc<AtomicBool>,
+    rep: &mut dyn BuildReporter,
+    dependency_stack: &mut Vec<PathBuf>,
+) -> Result<(), String> {
+    let root = project_root
+        .canonicalize()
+        .unwrap_or_else(|_| project_root.to_path_buf());
+    if let Some(index) = dependency_stack.iter().position(|item| item == &root) {
+        let mut chain: Vec<String> = dependency_stack[index..]
+            .iter()
+            .map(|item| item.display().to_string())
+            .collect();
+        chain.push(root.display().to_string());
+        return Err(format!("Dependency cycle detected: {}", chain.join(" -> ")));
+    }
+    dependency_stack.push(root);
+    let result = build_project_at_inner(
+        project_root,
+        profile,
+        target,
+        explicit_target,
+        exclude_dirs,
+        force,
+        verbose,
+        workspace_root,
+        cancel,
+        rep,
+        dependency_stack,
+    );
+    dependency_stack.pop();
+    result
+}
+
+/// Builds one DCR package after the dependency-cycle guard has been installed.
+#[allow(clippy::too_many_arguments)]
+fn build_project_at_inner(
+    project_root: &Path,
+    profile: &str,
+    target: Option<&str>,
+    explicit_target: bool,
+    exclude_dirs: &[std::path::PathBuf],
+    force: bool,
+    verbose: bool,
+    workspace_root: Option<&Path>,
+    cancel: &Arc<AtomicBool>,
+    rep: &mut dyn BuildReporter,
+    dependency_stack: &mut Vec<PathBuf>,
 ) -> Result<(), String> {
     if cancel.load(Ordering::SeqCst) {
         return Err("Build interrupted".to_string());
@@ -641,38 +716,34 @@ fn build_project_at(
         }
     }
 
-    let deps_table = config.get("dependencies").and_then(|v| v.as_table());
     let mut resolved = resolve_deps(&config, profile, build_target, project_root)?;
     resolved.include_dirs.extend(ws_include_dirs);
     resolved.lib_dirs.extend(ws_lib_dirs);
     resolved.libs.extend(ws_libs);
 
-    // Registry dependencies are cached under the DCR registry root. Build
-    // them as normal DCR projects before the current project is linked.
-    if let Some(deps) = deps_table {
-        for (name, value) in deps {
-            if register::is_registry_dep(value) {
-                let pkg_info = register::resolve_package_from_registry(name)?;
-                let version = pkg_info
-                    .get("latest_version")
-                    .or_else(|| pkg_info.get("version"))
-                    .and_then(|v| v.as_str())
-                    .unwrap_or("unknown");
-                let dep_root = register::package_root_from_registry_info(&pkg_info)?;
-                let include_dir = dep_root.join("target").join("include");
-                let lib_dir = dep_root.join("target").join("lib");
-
-                if !include_dir.exists() || !lib_dir.exists() {
-                    rep.on_event(BuildEvent::DepBuilding { name, version });
-                    if !dep_root.join("dcr.toml").is_file() {
-                        return Err(format!(
-                            "Registry dependency `{}` is missing dcr.toml at {}",
-                            name,
-                            dep_root.display()
-                        ));
+    let mut built_roots = std::collections::HashSet::new();
+    let mut transitive_roots = std::collections::HashSet::new();
+    let direct_package_roots = resolved.package_roots.clone();
+    for dep_root in &direct_package_roots {
+        if !built_roots.insert(dep_root.clone()) {
+            continue;
         }
-                    build_project_at(
-                        &dep_root,
+        let dep_root = Path::new(dep_root);
+        let dep_config =
+            Config::open(&dep_root.join("dcr.toml").to_string_lossy()).map_err(|_| {
+                format!(
+                    "DCR dependency is missing dcr.toml at {}",
+                    dep_root.display()
+                )
+            })?;
+        let name = get_config_str(&dep_config, "package.name");
+        let version = get_config_str(&dep_config, "package.version");
+        rep.on_event(BuildEvent::DepBuilding {
+            name: &name,
+            version: &version,
+        });
+        build_project_at_with_stack(
+            dep_root,
             profile,
             build_target,
             has_explicit_target,
@@ -682,21 +753,20 @@ fn build_project_at(
             None,
             cancel,
             &mut *rep,
+            dependency_stack,
         )?;
         rep.on_event(BuildEvent::DepReady {
-                        name,
-                        version,
+            name: &name,
+            version: &version,
             rebuilt: true,
         });
-                } else {
-                    rep.on_event(BuildEvent::DepReady {
-                        name,
-                        version,
-                        rebuilt: false,
-                    });
-                }
-            }
-        }
+        extend_transitive_link_deps(
+            dep_root,
+            profile,
+            build_target,
+            &mut resolved,
+            &mut transitive_roots,
+        )?;
     }
 
     let (resolved_cflags, resolved_ldflags) =
@@ -919,6 +989,40 @@ fn build_project_at(
     Ok(())
 }
 
+/// Adds link flags needed by dependencies of a static DCR library.
+/// Static archives do not contain their own dependency objects, so the final
+/// consumer must link every transitive package in dependency order.
+fn extend_transitive_link_deps(
+    package_root: &Path,
+    profile: &str,
+    target: Option<&str>,
+    consumer_deps: &mut crate::core::deps::common::ResolvedDeps,
+    visited: &mut std::collections::HashSet<PathBuf>,
+) -> Result<(), String> {
+    let root = package_root
+        .canonicalize()
+        .unwrap_or_else(|_| package_root.to_path_buf());
+    if !visited.insert(root.clone()) {
+        return Ok(());
+    }
+    let config =
+        Config::open(&root.join("dcr.toml").to_string_lossy()).map_err(|err| err.to_string())?;
+    let deps = resolve_deps(&config, profile, target, &root)?;
+    consumer_deps.include_dirs.extend(deps.include_dirs);
+    consumer_deps.lib_dirs.extend(deps.lib_dirs);
+    consumer_deps.libs.extend(deps.libs);
+    for child_root in deps.package_roots {
+        extend_transitive_link_deps(
+            Path::new(&child_root),
+            profile,
+            target,
+            consumer_deps,
+            visited,
+        )?;
+    }
+    Ok(())
+}
+
 /// Converts relative paths in flags to absolute paths based on project root for include and link flags.
 fn absolutize_flag_path(flag: &str, project_root: &Path, prefixes: &[&str]) -> String {
     for prefix in prefixes {

src/core/deps/common.rs

@@ -4,4 +4,5 @@ pub struct ResolvedDeps {
     pub include_dirs: Vec<String>,
     pub lib_dirs: Vec<String>,
     pub libs: Vec<String>,
+    pub package_roots: Vec<String>,
 }

src/core/deps/mod.rs

@@ -39,8 +39,8 @@ fn dep_version(path: &Path) -> String {
 
 /// Resolves dependencies from config into include/lib dirs and lib names, and writes the lock file.
 ///
-/// Registry and path deps contribute to `ResolvedDeps`. Git deps are recorded in the lock only
-/// (no fetch or include/lib resolution).
+/// Registry, path, and git deps contribute to `ResolvedDeps`. Path and git sources support both
+/// DCR packages (built from `dcr.toml`) and prebuilt libraries (described with include/lib/libs).
 ///
 /// # Parameters
 /// - `config`: Loaded `dcr.toml`.
@@ -88,6 +88,9 @@ pub fn resolve_deps(
                         .to_string(),
                 );
                 resolved.libs.push(name.clone());
+                resolved
+                    .package_roots
+                    .push(dep_root.to_string_lossy().to_string());
 
                 lock_packages.push(DepLock {
                     name: name.clone(),
@@ -107,6 +110,8 @@ pub fn resolve_deps(
                 });
             } else if let Some(path) = path_dep_path(value) {
                 let dep_root = project_root.join(path);
+                let dcr_package_name = package_name(&dep_root);
+                let use_dcr_package = use_dcr_package(value, dcr_package_name.is_some(), name)?;
                 if let Some(table) = value.as_table() {
                     if let Some(includes) = table.get("include").and_then(|v| v.as_array()) {
                         for inc in includes {
@@ -118,10 +123,7 @@ pub fn resolve_deps(
                         }
                     } else {
                         push_if_exists(&mut resolved.include_dirs, &dep_root.join("include"));
-                        push_if_exists(
-                            &mut resolved.include_dirs,
-                            &dep_root.join("target").join("include"),
-                        );
+                        push_package_output_dirs(&mut resolved, &dep_root);
                     }
 
                     if let Some(lib_dirs) = table.get("lib").and_then(|v| v.as_array()) {
@@ -143,16 +145,29 @@ pub fn resolve_deps(
                             }
                         }
                     } else {
-                        resolved.libs.push(name.clone());
+                        resolved
+                            .libs
+                            .push(dcr_package_name.clone().unwrap_or_else(|| name.clone()));
                     }
                 } else {
                     push_if_exists(&mut resolved.include_dirs, &dep_root.join("include"));
-                    push_if_exists(
-                        &mut resolved.include_dirs,
-                        &dep_root.join("target").join("include"),
-                    );
+                    push_package_output_dirs(&mut resolved, &dep_root);
                     push_default_lib_dirs(&mut resolved.lib_dirs, &dep_root);
-                    resolved.libs.push(name.clone());
+                    resolved
+                        .libs
+                        .push(dcr_package_name.clone().unwrap_or_else(|| name.clone()));
+                }
+
+                if use_dcr_package {
+                    resolved
+                        .package_roots
+                        .push(dep_root.to_string_lossy().to_string());
+                    push_package_output_dirs(&mut resolved, &dep_root);
+                } else if !has_complete_prebuilt_layout(value) {
+                    return Err(format!(
+                        "Path dependency `{}` has no dcr.toml; specify include, lib, and libs for a prebuilt library",
+                        name
+                    ));
                 }
 
                 lock_packages.push(DepLock {
@@ -162,11 +177,46 @@ pub fn resolve_deps(
                     source: format!("path+{}", dep_root.display()),
                 });
             } else if let Some(git_info) = git_dep(value) {
+                let dep_root = register::fetch_git_dependency(
+                    git_info.url,
+                    git_info.branch.as_deref(),
+                    git_info.tag.as_deref(),
+                    git_info.rev.as_deref(),
+                )?;
+                let dcr_package_name = package_name(&dep_root);
+                let use_dcr_package = use_dcr_package(value, dcr_package_name.is_some(), name)?;
+                let (has_include, has_lib, has_libs) = value
+                    .as_table()
+                    .map(|table| push_explicit_layout(&mut resolved, &dep_root, table))
+                    .unwrap_or((false, false, false));
+                if !has_include {
+                    push_if_exists(&mut resolved.include_dirs, &dep_root.join("include"));
+                    if use_dcr_package {
+                        push_package_output_dirs(&mut resolved, &dep_root);
+                    }
+                }
+                if !has_lib {
+                    push_default_lib_dirs(&mut resolved.lib_dirs, &dep_root);
+                }
+                if !has_libs && let Some(package_name) = dcr_package_name.as_deref() {
+                    resolved.libs.push(package_name.to_string());
+                }
+                if use_dcr_package {
+                    resolved
+                        .package_roots
+                        .push(dep_root.to_string_lossy().to_string());
+                } else if !(has_include && has_lib && has_libs) {
+                    return Err(format!(
+                        "Git dependency `{}` has no dcr.toml; specify include, lib, and libs for a prebuilt library",
+                        name
+                    ));
+                }
+                let commit = register::git_commit(&dep_root)?;
                 lock_packages.push(DepLock {
                     name: name.clone(),
-                    version: git_info.version.unwrap_or_default(),
-                    checksum: String::new(),
-                    source: format!("git+{}", git_info.url),
+                    version: git_info.version.unwrap_or(commit.clone()),
+                    checksum: commit.clone(),
+                    source: format!("git+{}#{}", git_info.url, commit),
                 });
             }
         }
@@ -187,6 +237,9 @@ pub fn resolve_deps(
 struct GitDep<'a> {
     url: &'a str,
     version: Option<String>,
+    branch: Option<String>,
+    tag: Option<String>,
+    rev: Option<String>,
 }
 
 /// Parses a git dependency from a TOML value table.
@@ -198,7 +251,25 @@ fn git_dep(value: &toml::Value) -> Option<GitDep<'_>> {
             .get("version")
             .and_then(|v| v.as_str())
             .map(|s| s.to_string());
-        return Some(GitDep { url, version });
+        let branch = table
+            .get("branch")
+            .and_then(|v| v.as_str())
+            .map(str::to_string);
+        let tag = table
+            .get("tag")
+            .and_then(|v| v.as_str())
+            .map(str::to_string);
+        let rev = table
+            .get("rev")
+            .and_then(|v| v.as_str())
+            .map(str::to_string);
+        return Some(GitDep {
+            url,
+            version,
+            branch,
+            tag,
+            rev,
+        });
     }
     None
 }
@@ -226,6 +297,117 @@ fn push_default_lib_dirs(paths: &mut Vec<String>, dep_root: &Path) {
     push_if_exists(paths, &dep_root.join("target").join("lib"));
 }
 
+/// Adds explicitly configured prebuilt include/lib directories and linker names.
+fn push_explicit_layout(
+    resolved: &mut ResolvedDeps,
+    dep_root: &Path,
+    table: &toml::map::Map<String, toml::Value>,
+) -> (bool, bool, bool) {
+    let mut has_include = false;
+    let mut has_lib = false;
+    let mut has_libs = false;
+    if let Some(includes) = table.get("include").and_then(|v| v.as_array()) {
+        has_include = true;
+        for inc in includes {
+            if let Some(path) = inc.as_str() {
+                resolved
+                    .include_dirs
+                    .push(dep_root.join(path).to_string_lossy().to_string());
+            }
+        }
+    }
+    if let Some(lib_dirs) = table.get("lib").and_then(|v| v.as_array()) {
+        has_lib = true;
+        for path in lib_dirs {
+            if let Some(path) = path.as_str() {
+                resolved
+                    .lib_dirs
+                    .push(dep_root.join(path).to_string_lossy().to_string());
+            }
+        }
+    }
+    if let Some(libs) = table.get("libs").and_then(|v| v.as_array()) {
+        has_libs = true;
+        for lib in libs {
+            if let Some(name) = lib.as_str() {
+                resolved.libs.push(name.to_string());
+            }
+        }
+    }
+    (has_include, has_lib, has_libs)
+}
+
+/// Reports whether a source without a DCR manifest fully describes its prebuilt layout.
+fn has_complete_prebuilt_layout(value: &toml::Value) -> bool {
+    value.as_table().is_some_and(|table| {
+        ["include", "lib", "libs"].iter().all(|field| {
+            table
+                .get(*field)
+                .and_then(|value| value.as_array())
+                .is_some_and(|values| !values.is_empty())
+        })
+    })
+}
+
+/// Selects automatic, forced-build, or forced-prebuilt dependency resolution.
+fn use_dcr_package(
+    value: &toml::Value,
+    has_manifest: bool,
+    dependency_name: &str,
+) -> Result<bool, String> {
+    let mode = value
+        .as_table()
+        .and_then(|table| table.get("mode"))
+        .map(|value| {
+            value.as_str().ok_or_else(|| {
+                format!(
+                    "Dependency `{dependency_name}` field `mode` must be \"build\" or \"prebuild\""
+                )
+            })
+        })
+        .transpose()?;
+    match mode {
+        None => Ok(has_manifest),
+        Some("build") if has_manifest => Ok(true),
+        Some("build") => Err(format!(
+            "Dependency `{dependency_name}` uses mode = \"build\" but has no dcr.toml"
+        )),
+        Some("prebuild") => Ok(false),
+        Some(_) => Err(format!(
+            "Dependency `{dependency_name}` field `mode` must be \"build\" or \"prebuild\""
+        )),
+    }
+}
+
+/// Adds DCR's packaged output directories even before the dependency is built.
+fn push_package_output_dirs(resolved: &mut ResolvedDeps, dep_root: &Path) {
+    push_unique_path(
+        &mut resolved.include_dirs,
+        dep_root.join("target").join("include"),
+    );
+    push_unique_path(&mut resolved.lib_dirs, dep_root.join("target").join("lib"));
+}
+
+/// Adds a path once, preserving the linker and include-search order.
+fn push_unique_path(paths: &mut Vec<String>, path: std::path::PathBuf) {
+    let path = path.to_string_lossy().to_string();
+    if !paths.contains(&path) {
+        paths.push(path);
+    }
+}
+
+/// Reads a DCR package name when the dependency has a manifest.
+fn package_name(path: &Path) -> Option<String> {
+    Config::open(&path.join("dcr.toml").to_string_lossy())
+        .ok()
+        .and_then(|config| {
+            config
+                .get("package.name")
+                .and_then(|value| value.as_str())
+                .map(str::to_string)
+        })
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

src/core/deps/register.rs

@@ -17,8 +17,10 @@
 
 use serde::{Deserialize, Serialize};
 use serde_json::Value as JsonValue;
+use sha2::{Digest, Sha256};
 use std::fs;
 use std::path::{Path, PathBuf};
+use std::process::Command;
 use toml::Value as TomlValue;
 
 /// Represents a registry configuration entry with its URL and priority.
@@ -149,6 +151,95 @@ pub fn registry_lib_dir(dep_root: &Path) -> PathBuf {
     dep_root.join("target").join("lib")
 }
 
+/// Fetches a git dependency into the DCR cache and returns its working tree.
+/// The URL and selected ref determine the cache key; an existing checkout is reused.
+pub fn fetch_git_dependency(
+    url: &str,
+    branch: Option<&str>,
+    tag: Option<&str>,
+    rev: Option<&str>,
+) -> Result<PathBuf, String> {
+    if !crate::utils::git::is_git_available() {
+        return Err("git executable not found in PATH".to_string());
+    }
+    let mut hasher = Sha256::new();
+    hasher.update(url.as_bytes());
+    hasher.update(b"\0");
+    hasher.update(branch.unwrap_or("").as_bytes());
+    hasher.update(b"\0");
+    hasher.update(tag.unwrap_or("").as_bytes());
+    hasher.update(b"\0");
+    hasher.update(rev.unwrap_or("").as_bytes());
+    let key = format!("{:x}", hasher.finalize());
+    let root = dcr_config_dir()
+        .unwrap_or_else(|| PathBuf::from("."))
+        .join("git")
+        .join(&key);
+    if root.join(".git").is_dir() {
+        let status = Command::new("git")
+            .args(["fetch", "--all", "--tags", "--prune"])
+            .current_dir(&root)
+            .status()
+            .map_err(|e| format!("failed to execute git fetch: {e}"))?;
+        if !status.success() {
+            eprintln!("Warning: git fetch failed for {url}; using the cached checkout");
+        }
+        return checkout_git_ref(&root, branch, tag, rev);
+    }
+    if root.exists() {
+        return Err(format!(
+            "git cache path is not a repository: {}",
+            root.display()
+        ));
+    }
+    if let Some(parent) = root.parent() {
+        fs::create_dir_all(parent).map_err(|e| format!("failed to create git cache: {e}"))?;
+    }
+    let status = Command::new("git")
+        .args(["clone", "--", url])
+        .arg(&root)
+        .status()
+        .map_err(|e| format!("failed to execute git clone: {e}"))?;
+    if !status.success() {
+        return Err(format!("git clone failed for {url}"));
+    }
+    checkout_git_ref(&root, branch, tag, rev)
+}
+
+/// Returns the exact commit checked out in a cached git dependency.
+pub fn git_commit(root: &Path) -> Result<String, String> {
+    let output = Command::new("git")
+        .args(["rev-parse", "HEAD"])
+        .current_dir(root)
+        .output()
+        .map_err(|e| format!("failed to execute git rev-parse: {e}"))?;
+    if !output.status.success() {
+        return Err(format!("failed to read git revision at {}", root.display()));
+    }
+    Ok(String::from_utf8_lossy(&output.stdout).trim().to_string())
+}
+
+fn checkout_git_ref(
+    root: &Path,
+    branch: Option<&str>,
+    tag: Option<&str>,
+    rev: Option<&str>,
+) -> Result<PathBuf, String> {
+    let selected = rev.or(tag).or(branch);
+    let Some(reference) = selected else {
+        return Ok(root.to_path_buf());
+    };
+    let status = Command::new("git")
+        .args(["checkout", "--force", reference])
+        .current_dir(root)
+        .status()
+        .map_err(|e| format!("failed to execute git checkout: {e}"))?;
+    if !status.success() {
+        return Err(format!("git checkout failed for ref `{reference}`"));
+    }
+    Ok(root.to_path_buf())
+}
+
 /// Looks up `name` in the local package index (`DCR_INDEX_PATH` / `~/.dcr/index.json`).
 ///
 /// Configured registries are sorted by priority, but the lookup currently always reads the

tests/cli_deps.rs

@@ -16,6 +16,15 @@ fn dcr_add_dependencies() {
         "path dep not found in toml"
     );
 
+    // A bare filesystem path is equivalent to the explicit path: form.
+    let out = run_dcr(&["add", "otherlib", "../otherlib"], &dir);
+    assert!(out.status.success(), "dcr add bare path should succeed");
+    let toml = std::fs::read_to_string(dir.join("dcr.toml")).unwrap();
+    assert!(
+        toml.contains("otherlib = { path = \"../otherlib\" }"),
+        "bare path dep not found in toml"
+    );
+
     // Test github: prefix
     let out = run_dcr(&["add", "gh_lib", "github:user/repo"], &dir);
     assert!(out.status.success(), "dcr add github should succeed");
@@ -96,6 +105,369 @@ fn dcr_builds_lib_package() {
     assert!(target_dir.join("lib").exists(), "lib directory missing");
 }
 
+#[test]
+fn path_prebuilt_dependency_without_manifest_links() {
+    let Some(compiler) = available_compiler() else {
+        eprintln!("no compiler found; skipping prebuilt path dependency test");
+        return;
+    };
+    if !is_ar_in_path() {
+        eprintln!("ar unavailable; skipping prebuilt path dependency test");
+        return;
+    }
+
+    let root = unique_sandbox_dir("path_prebuilt_dep");
+    let dep = root.join("dep");
+    let app = root.join("app");
+    write_prebuilt_library(
+        &dep,
+        compiler,
+        "prebuilt",
+        "int prebuilt_answer(void);\n",
+        "int prebuilt_answer(void) { return 42; }\n",
+    );
+    std::fs::create_dir_all(app.join("src")).unwrap();
+    std::fs::write(
+        app.join("dcr.toml"),
+        "[package]\nname = \"app\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"bin\"\n\n[dependencies]\nprebuilt = { path = \"../dep\", include = [\"include\"], lib = [\"lib\"], libs = [\"prebuilt\"] }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("src/main.c"),
+        "#include \"prebuilt.h\"\nint main(void) { return prebuilt_answer() == 42 ? 0 : 1; }\n",
+    )
+    .unwrap();
+
+    let out = run_dcr_env(&["build"], &app, &[("DCR_COMPILER", compiler)]);
+    assert!(
+        out.status.success(),
+        "prebuilt path dependency build failed: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+}
+
+#[test]
+fn path_dcr_dependency_is_built_before_consumer() {
+    let Some(compiler) = available_compiler() else {
+        eprintln!("no compiler found; skipping path dependency build test");
+        return;
+    };
+    let root = unique_sandbox_dir("path_dcr_dep");
+    let dep = root.join("dep");
+    let app = root.join("app");
+    std::fs::create_dir_all(dep.join("src")).unwrap();
+    std::fs::create_dir_all(app.join("src")).unwrap();
+    std::fs::write(
+        dep.join("dcr.toml"),
+        "[package]\nname = \"mathlib\"\nversion = \"0.1.0\"\ntype = \"lib\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"staticlib\"\n",
+    )
+    .unwrap();
+    std::fs::write(dep.join("src/mathlib.h"), "int answer(void);\n").unwrap();
+    std::fs::write(
+        dep.join("src/mathlib.c"),
+        "int answer(void) { return 42; }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("dcr.toml"),
+        "[package]\nname = \"app\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"bin\"\n\n[dependencies]\nrenamed = { path = \"../dep\" }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("src/main.c"),
+        "#include \"mathlib.h\"\nint main(void) { return answer() == 42 ? 0 : 1; }\n",
+    )
+    .unwrap();
+
+    let out = run_dcr_env(&["build"], &app, &[("DCR_COMPILER", compiler)]);
+    assert!(
+        out.status.success(),
+        "path dependency build failed: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    assert!(dep.join("target/include/mathlib.h").is_file());
+    assert!(dep.join("target/lib").is_dir());
+}
+
+#[test]
+fn path_dcr_dependencies_build_transitively() {
+    let Some(compiler) = available_compiler() else {
+        eprintln!("no compiler found; skipping transitive path dependency test");
+        return;
+    };
+    let root = unique_sandbox_dir("path_dcr_transitive");
+    let leaf = root.join("leaf");
+    let middle = root.join("middle");
+    let app = root.join("app");
+    for project in [&leaf, &middle, &app] {
+        std::fs::create_dir_all(project.join("src")).unwrap();
+    }
+    std::fs::write(
+        leaf.join("dcr.toml"),
+        "[package]\nname = \"leaf\"\nversion = \"0.1.0\"\ntype = \"lib\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"staticlib\"\n",
+    )
+    .unwrap();
+    std::fs::write(leaf.join("src/leaf.h"), "int leaf_value(void);\n").unwrap();
+    std::fs::write(
+        leaf.join("src/leaf.c"),
+        "int leaf_value(void) { return 40; }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        middle.join("dcr.toml"),
+        "[package]\nname = \"middle\"\nversion = \"0.1.0\"\ntype = \"lib\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"staticlib\"\n\n[dependencies]\nleaf = { path = \"../leaf\" }\n",
+    )
+    .unwrap();
+    std::fs::write(middle.join("src/middle.h"), "int middle_value(void);\n").unwrap();
+    std::fs::write(
+        middle.join("src/middle.c"),
+        "#include \"leaf.h\"\nint middle_value(void) { return leaf_value() + 2; }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("dcr.toml"),
+        "[package]\nname = \"app\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"bin\"\n\n[dependencies]\nmiddle = { path = \"../middle\" }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("src/main.c"),
+        "#include \"middle.h\"\nint main(void) { return middle_value() == 42 ? 0 : 1; }\n",
+    )
+    .unwrap();
+
+    let out = run_dcr_env(&["build"], &app, &[("DCR_COMPILER", compiler)]);
+    assert!(
+        out.status.success(),
+        "transitive path dependency build failed: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    assert!(leaf.join("target/lib").is_dir());
+    assert!(middle.join("target/lib").is_dir());
+}
+
+#[test]
+fn path_dependency_cycle_reports_the_full_chain() {
+    let root = unique_sandbox_dir("path_dcr_cycle");
+    let first = root.join("first");
+    let second = root.join("second");
+    for project in [&first, &second] {
+        std::fs::create_dir_all(project.join("src")).unwrap();
+    }
+    std::fs::write(
+        first.join("dcr.toml"),
+        "[package]\nname = \"first\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\nkind = \"staticlib\"\n\n[dependencies]\nsecond = { path = \"../second\" }\n",
+    )
+    .unwrap();
+    std::fs::write(
+        second.join("dcr.toml"),
+        "[package]\nname = \"second\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\nkind = \"staticlib\"\n\n[dependencies]\nfirst = { path = \"../first\" }\n",
+    )
+    .unwrap();
+
+    let out = run_dcr(&["build"], &first);
+    let stderr = String::from_utf8_lossy(&out.stderr);
+    assert!(!out.status.success());
+    assert!(stderr.contains("Dependency cycle detected"), "{stderr}");
+    assert!(
+        stderr.contains("first") && stderr.contains("second"),
+        "{stderr}"
+    );
+}
+
+#[test]
+fn git_dcr_dependency_is_cloned_built_and_locked() {
+    let Some(compiler) = available_compiler() else {
+        eprintln!("no compiler found; skipping git dependency build test");
+        return;
+    };
+    if !is_git_in_path() {
+        eprintln!("git unavailable; skipping git dependency build test");
+        return;
+    }
+    let root = unique_sandbox_dir("git_dcr_dep");
+    let home = root.join("home");
+    let origin = root.join("origin");
+    let app = root.join("app");
+    std::fs::create_dir_all(origin.join("src")).unwrap();
+    std::fs::create_dir_all(app.join("src")).unwrap();
+    std::fs::write(
+        origin.join("dcr.toml"),
+        "[package]\nname = \"gitmath\"\nversion = \"0.1.0\"\ntype = \"lib\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"staticlib\"\n",
+    )
+    .unwrap();
+    std::fs::write(origin.join("src/gitmath.h"), "int git_answer(void);\n").unwrap();
+    std::fs::write(
+        origin.join("src/gitmath.c"),
+        "int git_answer(void) { return 7; }\n",
+    )
+    .unwrap();
+    for args in [
+        vec!["init"],
+        vec!["add", "."],
+        vec![
+            "-c",
+            "user.email=dcr@example.test",
+            "-c",
+            "user.name=DCR",
+            "commit",
+            "-m",
+            "init",
+        ],
+        vec!["tag", "v0.1.0"],
+    ] {
+        let status = std::process::Command::new("git")
+            .args(args)
+            .current_dir(&origin)
+            .status()
+            .unwrap();
+        assert!(status.success());
+    }
+    // TOML basic strings treat backslashes as escapes. Git for Windows emits
+    // paths with `\\`, so normalize the local repository path before embedding
+    // it into dcr.toml (the slash form is accepted by Git on every platform).
+    let origin_url = origin.to_string_lossy().replace('\\', "/");
+    std::fs::write(
+        app.join("dcr.toml"),
+        format!("[package]\nname = \"app\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"bin\"\n\n[dependencies]\ngitmath = {{ git = \"{origin_url}\", tag = \"v0.1.0\" }}\n"),
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("src/main.c"),
+        "#include \"gitmath.h\"\nint main(void) { return git_answer() == 7 ? 0 : 1; }\n",
+    )
+    .unwrap();
+    let home_s = home.to_string_lossy().to_string();
+    let out = run_dcr_env(
+        &["build"],
+        &app,
+        &[("DCR_COMPILER", compiler), ("HOME", home_s.as_str())],
+    );
+    assert!(
+        out.status.success(),
+        "git dependency build failed: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    let lock = std::fs::read_to_string(app.join("dcr.lock")).unwrap();
+    assert!(lock.contains("git+"));
+    assert!(!lock.contains("checksum = \"\""));
+}
+
+#[test]
+fn git_prebuilt_dependency_without_manifest_links() {
+    let Some(compiler) = available_compiler() else {
+        eprintln!("no compiler found; skipping prebuilt git dependency test");
+        return;
+    };
+    if !is_git_in_path() || !is_ar_in_path() {
+        eprintln!("git or ar unavailable; skipping prebuilt git dependency test");
+        return;
+    }
+
+    let root = unique_sandbox_dir("git_prebuilt_dep");
+    let home = root.join("home");
+    let origin = root.join("origin");
+    let app = root.join("app");
+    write_prebuilt_library(
+        &origin,
+        compiler,
+        "gitprebuilt",
+        "int git_prebuilt_answer(void);\n",
+        "int git_prebuilt_answer(void) { return 9; }\n",
+    );
+    std::fs::create_dir_all(app.join("src")).unwrap();
+    for args in [
+        vec!["init"],
+        vec!["add", "."],
+        vec![
+            "-c",
+            "user.email=dcr@example.test",
+            "-c",
+            "user.name=DCR",
+            "commit",
+            "-m",
+            "init",
+        ],
+        vec!["tag", "v0.1.0"],
+    ] {
+        let status = std::process::Command::new("git")
+            .args(args)
+            .current_dir(&origin)
+            .status()
+            .unwrap();
+        assert!(status.success());
+    }
+    // Keep the Git source TOML-safe on Windows (`C:/...`, not `C:\\...`).
+    let origin_url = origin.to_string_lossy().replace('\\', "/");
+    std::fs::write(
+        app.join("dcr.toml"),
+        format!("[package]\nname = \"app\"\nversion = \"0.1.0\"\n\n[build]\nlanguage = \"c\"\ncompiler = \"clang\"\nkind = \"bin\"\n\n[dependencies]\ngitprebuilt = {{ git = \"{origin_url}\", tag = \"v0.1.0\", include = [\"include\"], lib = [\"lib\"], libs = [\"gitprebuilt\"] }}\n"),
+    )
+    .unwrap();
+    std::fs::write(
+        app.join("src/main.c"),
+        "#include \"gitprebuilt.h\"\nint main(void) { return git_prebuilt_answer() == 9 ? 0 : 1; }\n",
+    )
+    .unwrap();
+
+    let home_s = home.to_string_lossy().to_string();
+    let out = run_dcr_env(
+        &["build"],
+        &app,
+        &[("DCR_COMPILER", compiler), ("HOME", home_s.as_str())],
+    );
+    assert!(
+        out.status.success(),
+        "prebuilt git dependency build failed: {}",
+        String::from_utf8_lossy(&out.stderr)
+    );
+    let lock = std::fs::read_to_string(app.join("dcr.lock")).unwrap();
+    assert!(lock.contains("git+"));
+    assert!(!lock.contains("checksum = \"\""));
+}
+
+fn write_prebuilt_library(
+    root: &std::path::Path,
+    compiler: &str,
+    name: &str,
+    header: &str,
+    source: &str,
+) {
+    let include_dir = root.join("include");
+    let lib_dir = root.join("lib");
+    let src_dir = root.join("src");
+    std::fs::create_dir_all(&include_dir).unwrap();
+    std::fs::create_dir_all(&lib_dir).unwrap();
+    std::fs::create_dir_all(&src_dir).unwrap();
+    std::fs::write(include_dir.join(format!("{name}.h")), header).unwrap();
+    let source_path = src_dir.join(format!("{name}.c"));
+    let object_path = lib_dir.join(format!("{name}.o"));
+    let archive_path = lib_dir.join(format!("lib{name}.a"));
+    std::fs::write(&source_path, source).unwrap();
+    let status = std::process::Command::new(compiler)
+        .args(["-c"])
+        .arg(&source_path)
+        .args(["-o"])
+        .arg(&object_path)
+        .status()
+        .unwrap();
+    assert!(status.success(), "failed to compile prebuilt library");
+    let status = std::process::Command::new("ar")
+        .args(["rcs"])
+        .arg(&archive_path)
+        .arg(&object_path)
+        .status()
+        .unwrap();
+    assert!(status.success(), "failed to archive prebuilt library");
+}
+
+fn is_ar_in_path() -> bool {
+    std::process::Command::new("ar")
+        .arg("--version")
+        .output()
+        .map(|out| out.status.success())
+        .unwrap_or(false)
+}
+
 #[test]
 fn registry_dependency_is_built_from_cache() {
     let Some(compiler) = available_compiler() else {