Feature Request: Add native Zellij terminal multiplexer support

[mrdavidlaing-mo]

Summary

Request to native support for Zellij as an alternative to tmux for terminal multiplexer integration.

Current State

I'm really excited about the new Oh-my-opencode tmux integration:

1. Tool Layer (interactive_bash): Execute tmux subcommands for TUI apps (vim, htop, etc.)
2. Hook Layer (interactive-bash-session): Track and auto-cleanup tmux sessions
3. Feature Layer (tmux-subagent): Spawn visual panes for background agents

Problem

However, I'm a Zellij user :(

Offer to Contribute

Would you accept a PR implementing this feature?

I've detailed in a comment below the approach I'd take.

Let me know if you're interested.

Thanks for an awesome plugin!

Omomomomo!

[mrdavidlaing-mo]

Proposed Solution

Implement a terminal multiplexer abstraction layer with support for both tmux and zellij:

Phase 1: Create Abstraction Interface

// src/shared/terminal-multiplexer/interface.ts
interface TerminalMultiplexer {
  isAvailable(): Promise<boolean>
  isInside(): boolean
  createSession(name: string): Promise<void>
  killSession(name: string): Promise<void>
  spawnPane(cmd: string, options: SpawnOptions): Promise<string>
  closePane(id: string): Promise<void>
  queryPaneState(): Promise<PaneState[]>
}

Phase 2: Implement Both Backends

• TmuxMultiplexer: Migrate existing tmux code
• ZellijMultiplexer: New implementation using zellij action commands

Phase 3: Update Features

• Refactor interactive_bash → interactive_terminal (auto-detect multiplexer)
• Update interactive-bash-session hook to support both
• Update tmux-subagent → terminal-multiplexer-subagent

Phase 4: Configuration

{
  "terminal_multiplexer": {
    "type": "auto",  // "auto" | "tmux" | "zellij" | "disabled"
    "enabled": false,
    "layout": "main-vertical",
    // ... existing config options
  }
}

Implementation Considerations

Zellij vs Tmux Differences

Feature	Tmux	Zellij	Solution
Pane IDs	Stable (%42)	No stable IDs	Track by session name mapping
Layout control	Manual (select-layout)	Automatic	Accept zellij's auto-layout
Commands	tmux <subcommand>	zellij action <name>	Different command builders
State query	display -p format strings	dump-layout JSON	Different parsers

Command Translation Examples

Operation	Tmux	Zellij
New session	tmux new-session -s name	zellij attach -c name
Kill session	tmux kill-session -t name	zellij delete-session name
Split pane	tmux split-window -h	zellij action new-pane --direction right
Send keys	tmux send-keys "cmd" Enter	zellij action write-chars "cmd" + write 10

[justsisyphus]

Thanks for the detailed feature request and the comprehensive implementation proposal!

Current State Analysis

You've correctly identified the three-layer tmux integration:

• Tool Layer (): Direct tmux subcommand execution
• Hook Layer (): Session lifecycle management and cleanup
• Feature Layer (): Visual pane spawning for background agents

Your Proposal

Your 4-phase approach with the abstraction interface is well-structured and addresses the key differences between tmux and zellij:

• Stable pane ID handling (tmux %42 vs zellij's session-based tracking)
• Layout control differences (manual vs automatic)
• Command translation patterns

Next Steps

We'd be happy to review a PR implementing this feature. A few suggestions:

1. Start with Phase 1 (abstraction interface) to establish the contract
2. Migrate existing tmux code to the interface (Phase 2)
3. Implement zellij backend alongside
4. Update configuration schema and documentation

Please feel free to open a draft PR when ready. We can discuss implementation details and any architectural decisions there.

Thanks for contributing! 🎉

[mrdavidlaing]

👋🏼 #1226 contains my first implementation attempt.

I'm particularly interested in feedback around how much backward compatibility to keep w.r.t config and thoughts on the structure of the new "multi-multiplexer" config structure:

{
  "terminal": {
    "provider": "auto",  // "auto" | "tmux" | "zellij"
    "tmux": {
      "enabled": true,
      "session_prefix": "omo-"
    },
    "zellij": {
      "enabled": true,
      "session_prefix": "omo-"
    }
  }
}