Mjolnir
Mjolnir (mj) is a a meta-harness for managing all your coding agents in one place.
If you only ever use a single subscription in a single harness on a single machine, you don't need mjolnir.
But if you expand beyond that, Mjolnir offers flexibility across all three:
- Move sessions between subscriptions (personal codex to work codex)
- Move sessions across harnesses (codex to claude code)
- Move sessions across machines or containers (local workstation to ec2)
... while handling details like cross-harness memory sync and integrating a privacy-first, no-setup web ui via Tailscale for when you're not at your desk.
Mjolnir is free and open source from the engineers at Brokk AI. We're not trying to make money off of mj; we built it because we wanted to use it.
Documentation · Quickstart · Releases
Screenshots
Alternatives
The comparison below covers product capabilities. — means no first-class capability; manual scripts, host setup, and filesystem access are described where relevant. Compared against repository snapshots inspected on September 8, 2026: Herdr, Paseo, and T3 Code.
Provisioning
| Feature | Mjolnir | Herdr | Paseo | T3 Code |
|---|---|---|---|---|
| Remote targets | Anything reachable over SSH¹ | SSH machines with Herdr installed | Machines running a reachable Paseo daemon | SSH/WSL environments running a T3 backend |
| Remote execution | Uploads an on-demand session worker; no resident per-host daemon | Requires a Herdr server on each host | Requires a Paseo daemon on each host | Requires a T3 backend in each environment |
| EC2 | Provisions and terminates instances from launch templates | Manual setup as a remote host | Manual setup as a remote host | Manual setup as a remote environment |
| Session containers | Docker, Podman | — | — | — |
| Credential synchronization | Continuously syncs whitelisted credentials into live targets | Host-local credentials | Per-daemon credentials | Per-environment credentials |
Session continuity
| Feature | Mjolnir | Herdr | Paseo | T3 Code |
|---|---|---|---|---|
| Native-session adoption | All supported harnesses | No external adoption; only restarts sessions it was already supervising | All supported providers with native list/load support | No external adoption; continues T3-owned sessions |
| Resume sessions across profiles and harnesses | ✓ | Manual handoff | /paseo-handoff skill |
Same-harness only² |
| Cross-host move and restore | ✓ | — | — | — |
| Multi-repo projects | Bundles provision, checkpoint, review, move, and restore member repos together³ | Filesystem access only; separate workspaces or panes | Filesystem/provider access only; one root per workspace | Filesystem access only; one workspace root per project |
Harnesses and accounts
| Feature | Mjolnir | Herdr | Paseo | T3 Code |
|---|---|---|---|---|
| Supported harnesses | Claude Code, Codex, Kimi Code, Grok Build, DSH, Muse Code | Pi, OMP, Copilot, Devin, Kimi, Hermes, Qoder, Qwen, Droid, OpenCode, Kilo, MastraCode, Claude, Codex, Cursor, Amp, Grok, Antigravity, Kiro, Maki, Muse; any other CLI runs without agent-aware features | Claude, Codex, Copilot, OpenCode, Pi, OMP; catalog and custom ACP agents including Kimi, Cursor, Hermes, and Qwen | Codex, Claude, Cursor, Grok, OpenCode |
| Multiple profiles per harness | First-class named profiles | Manual wrappers and environment configuration | Custom provider aliases | Provider instances; continuation compatibility varies by harness |
| Usage and quota view | Live subscription quota by profile plus target capacity⁴ | — | Provider plan usage on demand | Token and API-cost analytics; not remaining subscription quota |
Assistance and control
| Feature | Mjolnir | Herdr | Paseo | T3 Code |
|---|---|---|---|---|
| Cross-session project memory | Synchronized project memory shared across sessions, profiles, harnesses, and targets | — | — | — |
| Automatic adversarial review | Built-in automatic or on-demand independent review | Scriptable through agent automation; no built-in review loop | Manual /paseo-advisor second opinion |
— |
| Control surfaces | TUI, web, CLI | TUI, CLI | Web, desktop, iOS, Android, CLI | Web, desktop, iOS, Android, CLI |
| Voice input | TUI and web dictation | — | Dictation and conversational voice mode | — |
Extensibility
| Feature | Mjolnir | Herdr | Paseo | T3 Code |
|---|---|---|---|---|
| Product plugins | — | Workflow packages with actions, event hooks, terminal panes, and link handlers | Full-stack client/server plugins: UI surfaces, RPCs, tools, providers, themes, and commands | — |
“Native-session adoption” means discovering a session created outside the product and bringing it under management. Ordinary same-harness continuation is excluded.
- Mjolnir's SSH targets require a supported Linux host and the documented runtime prerequisites. It also supports Apple's container runtime on compatible Macs. See targets.
- T3 continuation also requires compatible provider homes: Codex can share history across accounts using its shadow-home setup; separate Claude account homes cannot continue the same thread.
- Bundles apply to managed targets. DSH (DeepSeek Harness) and Muse Code currently accept one workspace root. Bare sessions can access neighboring repositories subject to harness permissions, but do not manage them as a bundle.
- Quota availability depends on the harness. Muse currently cannot use the project-memory tools or act as a reviewer. Cross-harness resume requires a configured utility-capable profile to generate the handoff; see durability and recovery.
Get started
Install the release bundle on Linux or macOS (use WSL2 on Windows):
|
Linux CLI releases target glibc 2.28 or newer on x86-64 and ARM64 with a standard GNU loader. The desktop application and voice helper have additional native system dependencies and may require a newer distribution. Alpine and NixOS loader environments are not currently supported by these GNU bundles.
From your project directory, run:
On first launch, Mjolnir creates a workspace from the current directory. If the
opened workspace has no live session, it starts one automatically using your
configured Codex account and prefers usable Podman, then Docker, then a local
directory target. This happens once while the dashboard opens; switching
workspace tabs only filters the list. Press Create for the full wizard, or
use mj setup to configure other harness accounts and targets. Run mj doctor
to check prerequisites.
Follow the quickstart for your first session. The installation guide covers npm, source builds, desktop dependencies, and portable workers.
Documentation
- Profiles and harnesses: accounts, login, credentials, skills, and runtime prerequisites.
- Targets and bundles: local, container, SSH, and EC2 environments; multi-repository projects and shared memory.
- Session lifecycle and durability: adoption, move, resume, checkpoints, and recovery.
- Terminal and web/desktop: controls and remote access.
- Adversarial review, configuration, CLI reference, and security boundaries.
The website source lives in docs/. For the previous product generation, see Mjolnir 1.x.
License
Mjolnir is licensed under GPL-3.0-only.