Part of the Ataraxy Labs stack — agent-native infrastructure for software development. See also: sem (semantic version control) · weave (entity-level merge driver) · inspect (semantic code review).

Read the manifesto: https://ataraxy-labs.com/#thesis · Essays: https://ataraxy-labs.com/blogs · LLMs: https://ataraxy-labs.com/llms.txt

opensessions

tmux is all you need. make tmux great again :)

opensessions is a sidebar for tmux when your sessions, agents, and localhost tabs start multiplying.

It lives inside your existing tmux workflow instead of replacing it: one small pane for session switching, agent state, repo breadcrumbs, and quick jumps back into the right terminal.

Built with Rust and ratatui for native performance and zero runtime dependencies.

tmux is the only supported mux today. There is older zellij integration code in the repo, but it is not stable enough to document as supported; we are looking for maintainers who want to help bring it back to that bar.

Install With TPM

Requirements:

• tmux
• cargo (install Rust)
• TPM

Add this to ~/.tmux.conf:

set -g @plugin 'Ataraxy-Labs/opensessions'

Then reload tmux and install plugins:

tmux source-file ~/.tmux.conf
~/.tmux/plugins/tpm/bin/install_plugins

Build the binaries:

cd ~/.tmux/plugins/opensessions
cargo build --release

Open the sidebar with prefix o → s.

TPM clones the repo into ~/.tmux/plugins/opensessions. The sidebar and server run as native Rust binaries from target/release/.

If you want the same setup as a single shell command:

grep -q "Ataraxy-Labs/opensessions" ~/.tmux.conf 2>/dev/null || printf '\nset -g @plugin '\''Ataraxy-Labs/opensessions'\''\n' >> ~/.tmux.conf && tmux source-file ~/.tmux.conf && ~/.tmux/plugins/tpm/bin/install_plugins && cd ~/.tmux/plugins/opensessions && cargo build --release

Update

Use TPM's built-in update (prefix + U) or run:

~/.tmux/plugins/tpm/bin/update_plugins opensessions

Then rebuild:

cd ~/.tmux/plugins/opensessions && cargo build --release

The plugin automatically restarts the server on update so it picks up the new binary. Toggle the sidebar back on with prefix o → s if it was open.

Uninstall

Run the uninstall script before removing the plugin files — it cleans up tmux hooks, keybindings, sidebar panes, and environment variables that would otherwise persist and cause glitching:

sh ~/.tmux/plugins/opensessions/integrations/tmux-plugin/scripts/uninstall.sh

Then remove the set -g @plugin 'Ataraxy-Labs/opensessions' line from ~/.tmux.conf and run prefix + alt + u (TPM uninstall).

Today

• Live agent state across sessions for Amp, Claude Code, Codex, and OpenCode.
• Per-thread unseen markers for done, error, and interrupted states.
• Session context in the UI: branch in the list, working directory in the detail panel, thread names, and detected localhost ports.
• Programmatic metadata API: agents and scripts push status, progress, and logs to the sidebar via HTTP.
• Fast switching with j/k, arrows, Tab, 1-9, session reordering, hide/restore, creation, and kill actions.
• prefix o → s and prefix o → t for sidebar focus and toggle, prefix o → e for sidebar-safe even-horizontal layout in the current window, prefix o → 1 through 9 for quick switching, optional no-prefix shortcuts, in-app theme switching, and plugin hooks for more mux providers or watchers.
• Native Rust sidebar built with ratatui 0.30 and crossterm 0.29, with a local WebSocket server on 127.0.0.1:7391.

Programmatic API

Scripts and agents can push custom metadata to the sidebar over HTTP — no binary needed:

# Set a status pill on a session
curl -X POST http://127.0.0.1:7391/set-status \
  -H 'content-type: application/json' \
  -d '{"session":"my-app","text":"Deploying","tone":"warn"}'

# Set progress
curl -X POST http://127.0.0.1:7391/set-progress \
  -H 'content-type: application/json' \
  -d '{"session":"my-app","current":3,"total":10,"label":"services"}'

# Push a log entry
curl -X POST http://127.0.0.1:7391/log \
  -H 'content-type: application/json' \
  -d '{"session":"my-app","message":"Tests passed","source":"ci","tone":"success"}'

Endpoints: /set-status, /set-progress, /log, /clear-log, /notify

Tones: neutral, info, success, warn, error — each with a distinct icon and color.

Full reference: docs/reference/programmatic-api.md

Local Development

Build and run from a local clone:

git clone https://github.com/Ataraxy-Labs/opensessions.git
cd opensessions
cargo build --release
cargo test

Start the sidebar manually (outside tmux, for testing):

cargo run -p opensessions-sidebar

Start the server:

cargo run -p opensessions-server

For the full tmux workflow with keybindings, troubleshooting, and configuration options, follow the guide below.

Docs

• Get started in tmux
• Set up Ghostty shortcuts
• Configuration reference
• Features and keybindings reference
• Programmatic API reference
• Architecture explanation
• Contracts and extension interfaces
• Plugin authoring guide

A Few Concrete Bits

• Session ordering is persisted in ~/.config/opensessions/session-order.json.
• Amp watcher reads ~/.local/share/amp/threads/*.json and clears unseen state from Amp's session.json when a thread becomes seen there.
• Claude Code watcher reads JSONL transcripts in ~/.claude/projects/.
• Codex watcher reads transcript JSONL files in ~/.codex/sessions/ or $CODEX_HOME/sessions/ and resolves sessions from turn_context.cwd.
• OpenCode watcher polls the SQLite database in ~/.local/share/opencode/opencode.db.
• Hidden sidebars are stashed in a tmux session named _os_stash, so they can come back without restarting the sidebar process.
• Clicking a detected port opens http://localhost:<port>.

Repo Layout

Apps

• apps/tui-rs/ — Rust ratatui sidebar client (connects to server over WebSocket)
• apps/server-rs/ — Rust server that assembles state from mux providers and agent watchers
• apps/sidebar-shim-rs/ — Lightweight shim for sidebar process management
• apps/tui/scripts/ — Shell scripts for tmux sidebar launch and session switching

Packages

• packages/runtime-rs/ — Shared Rust runtime: tmux provider, agent watchers, config, tracker, protocol
• packages/sidebar-core-rs/ — Core sidebar rendering logic, extractable for snapshot tests
• packages/sidebar-protocol-rs/ — Shared protocol types between server and sidebar

Integrations

• opensessions.tmux — Root TPM entrypoint for users
• integrations/tmux-plugin/ — tmux-facing scripts and host integration glue
• integrations/amp/ — Amp agent integration
• integrations/pi-extension/ — Pi extension integration

Current Caveats

• The app is effectively pinned to 127.0.0.1:7391 today.
• theme, sidebarWidth, sidebarPosition, plugins, and mux are wired through the runtime; other typed config fields are not all live yet.
• Inline theme objects exist in core, but the running server persists and broadcasts theme names.
• tmux is the only supported mux today.

Star History

License

MIT