Added:

- Workspace support (`[workspace]` with deps ordering)
- `clean --all` for workspace members
Changed:
- Project root discovery for `build/run/clean` (searches parent dirs)
- Workspace paths are excluded from root source scan
- Build output now uses a Cargo-style `Compiling <name> v<version>` line
- Build time now reports total time for the whole build stage (workspace included)
- Cache hits are silent (no compile line when nothing is rebuilt)
- Safer build cache: fingerprints include headers and resolved library files

src/core/workspace.rs

@@ -0,0 +1,124 @@
+use crate::core::config::Config;
+use std::collections::{HashMap, HashSet};
+use std::path::{Path, PathBuf};
+use toml::Value;
+
+#[derive(Debug, Clone)]
+pub struct WorkspaceMember {
+    pub name: String,
+    pub path: PathBuf,
+    pub deps: Vec<String>,
+}
+
+#[derive(Debug, Clone)]
+pub struct Workspace {
+    pub members: Vec<WorkspaceMember>,
+}
+
+pub fn parse_workspace(config: &Config, root: &Path) -> Result<Option<Workspace>, String> {
+    let table = match config.get("workspace").and_then(|v| v.as_table()) {
+        Some(t) => t,
+        None => return Ok(None),
+    };
+
+    let mut members = Vec::new();
+    for (name, value) in table {
+        let tbl = value
+            .as_table()
+            .ok_or_else(|| format!("workspace.{name} must be a table with path and deps"))?;
+        let path_raw = tbl
+            .get("path")
+            .and_then(|v| v.as_str())
+            .ok_or_else(|| format!("workspace.{name}.path is required"))?;
+        let path = resolve_path(root, path_raw)?;
+        if !path.join("dcr.toml").is_file() {
+            return Err(format!(
+                "workspace.{name}.path does not contain dcr.toml: {}",
+                path.display()
+            ));
+        }
+        let deps = parse_deps(tbl.get("deps"))?;
+        members.push(WorkspaceMember {
+            name: name.to_string(),
+            path,
+            deps,
+        });
+    }
+
+    let mut ws = Workspace { members };
+    ws.members = topo_sort(&ws.members)?;
+    Ok(Some(ws))
+}
+
+fn resolve_path(root: &Path, raw: &str) -> Result<PathBuf, String> {
+    let p = Path::new(raw);
+    let full = if p.is_absolute() {
+        p.to_path_buf()
+    } else {
+        root.join(p)
+    };
+    Ok(full)
+}
+
+fn parse_deps(value: Option<&Value>) -> Result<Vec<String>, String> {
+    let Some(value) = value else {
+        return Ok(Vec::new());
+    };
+    let arr = value
+        .as_array()
+        .ok_or_else(|| "workspace deps must be an array of strings".to_string())?;
+    let mut out = Vec::new();
+    for item in arr {
+        let s = item
+            .as_str()
+            .ok_or_else(|| "workspace deps must be an array of strings".to_string())?;
+        out.push(s.to_string());
+    }
+    Ok(out)
+}
+
+fn topo_sort(members: &[WorkspaceMember]) -> Result<Vec<WorkspaceMember>, String> {
+    let mut map = HashMap::new();
+    for m in members {
+        map.insert(m.name.clone(), m.clone());
+    }
+    let mut state: HashMap<String, u8> = HashMap::new();
+    let mut order: Vec<WorkspaceMember> = Vec::new();
+
+    for name in map.keys() {
+        if *state.get(name).unwrap_or(&0) == 0 {
+            visit(name, &map, &mut state, &mut order)?;
+        }
+    }
+    Ok(order)
+}
+
+fn visit(
+    name: &str,
+    map: &HashMap<String, WorkspaceMember>,
+    state: &mut HashMap<String, u8>,
+    order: &mut Vec<WorkspaceMember>,
+) -> Result<(), String> {
+    match state.get(name).copied().unwrap_or(0) {
+        1 => return Err(format!("workspace dependency cycle at {name}")),
+        2 => return Ok(()),
+        _ => {}
+    }
+    state.insert(name.to_string(), 1);
+    let member = map
+        .get(name)
+        .ok_or_else(|| format!("unknown workspace member {name}"))?;
+    let mut seen = HashSet::new();
+    for dep in &member.deps {
+        if !seen.insert(dep) {
+            continue;
+        }
+        if !map.contains_key(dep) {
+            return Err(format!("workspace dependency '{dep}' not found"));
+        }
+        visit(dep, map, state, order)?;
+    }
+    state.insert(name.to_string(), 2);
+    order.push(member.clone());
+    Ok(())
+}