relative path syntax '{}' is not supported, use '//{}' or '

Error message

relative path syntax '{}' is not supported, use '//{}'  or ':task' for current directory

What it means

During task-name pattern matching (get_matching), any pattern containing both '/' and ':' but not starting with '//' or ':' is rejected. Such a pattern looks like a monorepo project-path/task reference written with unsupported relative syntax, so mise fails fast instead of silently matching nothing.

Source

Thrown at src/task/mod.rs:3346

                .iter()
                .filter(|(name, _)| {
                    name.split_once('#').is_some_and(|(project, task)| {
                        project_matcher.is_match(project)
                            && task_name_matches(&task_matcher, task, false)
                    })
                })
                .map(|(_, task)| task)
                .unique()
                .collect());
        }

        // === Monorepo pattern matching ===
        // Only patterns starting with '//' or ':' are monorepo patterns
        // Reject patterns that look like monorepo paths but use wrong syntax (have / and : but don't start with // or :)
        if !pat.starts_with("//") && !pat.starts_with(':') {
            // Check if this looks like an attempt at a monorepo path with wrong syntax
            if pat.contains('/') && pat.contains(':') {
                bail!(
                    "relative path syntax '{}' is not supported, use '//{}'  or ':task' for current directory",
                    pat,
                    pat
                )
            }
            // If it doesn't contain glob syntax or ':', it's a simple task name
            if !pat.contains(['*', '?', '[', '{']) && !pat.contains("...") && !pat.contains(':') {
                // Prefer exact name matches; only fall back to extension-stripped
                // matches when there is no exact match. Otherwise a TOML task
                // "hello" and an auto-discovered file task "hello.sh" would both
                // match `mise run hello` and run the script twice (#10298).
                let exact: Vec<&T> = self
                    .iter()
                    .filter(|(k, _)| k.as_str() == pat)
                    .map(|(_, v)| v)
                    .collect();
                if !exact.is_empty() {
                    return Ok(exact);

View on GitHub (pinned to 6f52dcdf99)

Solutions

Use absolute monorepo syntax from the workspace root: '//apps/web:build'
Or reference a task in the current config's directory with ':build'
Or use the plain task name if it is unique: 'build'

Example fix

# before
depends = ["apps/web:build"]

# after
depends = ["//apps/web:build"]

Defensive patterns

Strategy: validation

Validate before calling

# reject path-like task refs missing the // or : prefix
python3 - <<'EOF'
import tomllib, sys
cfg = tomllib.load(open('mise.toml','rb'))
for name, t in cfg.get('tasks', {}).items():
    for d in t.get('depends', []):
        s = str(d)
        if '/' in s and ':' in s and not (s.startswith('//') or s.startswith(':')):
            sys.exit(f"{name}: use '//{s}' or ':task', got '{s}'")
print('ok')
EOF

Prevention

Memorize the two legal monorepo prefixes: '//path:task' (root-relative) and ':task' (current dir)
Let shell completion suggest task names instead of typing paths

When it happens

Trigger: depends = ["apps/web:build"] or running `mise run src/api:test` — the pattern contains '/' and ':' yet starts with neither '//' nor ':'. The bail fires in the non-monorepo branch of the matcher before any name comparison happens.

Common situations: Migrating from another task runner's path:task syntax (e.g. turbo/nx style); typing a monorepo path and forgetting the leading double slash; converting a shell script that cd's into a subdirectory and runs a task there.

Related errors

AI-assisted analysis of jdx/mise@6f52dcdf99 (2026-08-22). Data as JSON: /api/errors/0d28c2061a5d782b. Report an issue: GitHub.