v0.9.0

Added

• Unified package-manager resolution chain. runner run now follows a
  documented 8-step precedence — qualified syntax → --pm / --runner
  → RUNNER_PM / RUNNER_RUNNER → runner.toml → package.json
  (packageManager then devEngines.packageManager) → lockfile →
  PATH probe → terminal error — making toolchain selection
  predictable across Corepack, antfu/ni, mise, and pnpm v11+
  conventions. New src/resolver/ module owns the chain end-to-end.
• --pm / --runner global flags with RUNNER_PM / RUNNER_RUNNER
  env-var mirrors. Cross-ecosystem overrides like --pm cargo against
  a Node project fall through to detection rather than hijacking
  dispatch. CLI wins over env; empty env strings are treated as unset.
• runner.toml project config ([pm], [task_runner],
  [resolution], [sources.*]). Per-ecosystem PM overrides apply
  only when the named PM matches the requested ecosystem;
  [resolution].fallback controls the no-signal behavior.
• devEngines.packageManager parsing from package.json (OpenJS
  proposal, npm 10.9+). Single-object and array forms supported with
  per-entry onFail (ignore/warn/error). download collapses to
  warn since runner is not an installer. The legacy packageManager
  field still wins when both are present; manifest declarations win
  over lockfile signals (Corepack semantics) and emit a package.json
  warning when they disagree.
• Semver enforcement on devEngines.version. When the declared range
  doesn't match the installed PM's --version, onFail=warn emits a
  warning and onFail=error bails. Unparseable ranges or missing
  --version output skip the check silently so a partially-broken
  environment never blocks dispatch.
• --fallback policy (probe default | npm legacy | error) with
  RUNNER_FALLBACK env mirror. The default replaces the silent npm
  fallback with a canonical-order PATH probe (bun > pnpm > yarn > npm); when nothing matches, the user sees an actionable error
  listing every source that was checked.
• --explain flag (RUNNER_EXPLAIN env). Emits a one-line trace
  describing which chain step produced the PM decision: · runner resolved: pnpm via package.json "packageManager".
• runner doctor subcommand. Dumps every signal the resolver
  considers: detected PMs/runners, override sources in effect (with
  origin attribution), manifest declarations, lockfile presence,
  PATH probe results for each Node PM, the final decision, and any
  warnings. --json emits schema-versioned output for jq/scripts/bug
  reports.
• runner why <task> subcommand. Walks the source-selection chain for
  a single task: lists every candidate source with its (priority, depth, display_order, alias) tuple, names the winner, and renders
  the PM resolution trace when a package.json script is picked.
  --json available.
• Passthrough-wrapper detection generalized to every supported task
  runner. A package.json script like "build": "just build" is now
  recognized as a thin wrapper around just and deduped from
  completion candidates when the underlying runner exposes a same-
  named task. Recognized runners: turbo, just, make, task (go-task),
  nx, bacon, mise.
• Ecosystem enum (Node/Deno/Python/Rust/Go/Ruby/Php)
  formalizing the PM-to-ecosystem mapping used by override scoping.

Changed

• Task.passthrough_to_turbo: bool replaced by Task.passthrough_to: Option<TaskRunner> so wrappers around any runner — not just turbo —
  can be attributed at detection time and used by completion.
• cmd::run::run signature now takes a &ResolutionOverrides so the
  resolver-chosen PM also flows through the no-task fallback paths
  (bun test special case, npx-style exec). --pm npm against a
  Bun-detected project now correctly suppresses the bun-test fallback.
• Task selection unified into a single sort key (source_priority, source_depth, display_order, alias_last). Replaces the Deno-only
  depth path with a generic tiebreak that applies to every source.
  Every non-workspace-aware source now walks ancestors upward when
  computing source_depth so the tiebreak actually distinguishes
  nested Makefile/Justfile/Taskfile/bacon.toml configs from
  workspace-root ones.
• Resolver::resolve_node_pm returns Result<ResolvedPm> so manifest
  onFail=error and --fallback error can bubble up structured
  errors instead of bailing inside the resolver.

Fixed

• package.json packageManager: "deno@…" projects no longer require
  a deno.json alongside to be recognized as a Deno project.
• Stale doc comment on detect::push_package_json_tasks updated to
  reflect that passthrough detection covers every known runner, not
  just turbo.

What's Changed

• Add resolver module for package manager and task runner selection by @kjanat in #22

Full Changelog: v0.8.1...v0.9.0