tmux client library for Raku

Control tmux, connect to and create servers, navigate sessions, windows, and panes, send keys, watch for changes via control mode, capture pane contents.

Getting started

Install LibTmux, create and split panes, and find them through typed snapshots.

Examples

Run six complete programs against private tmux servers and compare their output.

tmux compatibility

Check the supported tmux releases and how the library handles newer ones.

API reference

Native signatures, RakuDoc and links for every public module, class and method.

Install

zef install 'LibTmux:auth<zef:libtmux>'

At a glance

Server → Session → LibTmux::Model::WindowLink → Window → Pane. Each level of the tmux hierarchy has its own entry in the Raku API, with the tmux object it wraps.

Type	Wraps
`LibTmux::Server`	A tmux server
`LibTmux::Model::Session`	A session, ID `$n`
`LibTmux::Model::Window`	A physical window linked into sessions, ID `@n`
`LibTmux::Model::Pane`	A pane in a window, ID `%n`
`LibTmux::Model::WindowLink`	A session-window association, with its index and active state

What it does

use LibTmux;

my $server = Server.start(:name<work>, :shell-command('exec cat'));
LEAVE $server.close if $server.defined;

my $before = $server.snapshot;
my $left = $before.panes.single.ref;
my $right = $left.split(:horizontal, :shell-command('exec cat'));
$left.set-title('editor');
$right.set-title('logs');

my $after = $server.snapshot;
my $editor = $after.panes.filter(*.title eq 'editor').single;
say "{$editor.title}: {$after.panes.elems} panes";

No tmux server yet

tmux before the first call: no server is running.

%0 cat

[work]

tmux after Server.start: added session work.

%0 cat

[work]

tmux after Server.snapshot: unchanged.

%0 cat

[work]

tmux after PaneSelection.single: unchanged, the call sent no command.

%0 cat

%1 cat

[work]

tmux after PaneRef.split: added pane %1 to window 0:sh.

%0 cat

%1 cat

[work]

tmux after PaneRef.set-title: unchanged.

%0 cat

%1 cat

[work]

tmux after PaneRef.set-title: unchanged.

%0 cat

%1 cat

[work]

tmux after Server.snapshot: unchanged.

%0 cat

%1 cat

[work]

tmux after PaneSelection.single: unchanged, the call sent no command.

No sessions

tmux after Server.close: the server has exited; the call sent no command.

Before the first call

No tmux server is running yet.

`Server.start` returned `Server`

{
  "socket": "libtmux-owned-AbC123"
}

1 tmux command, 1 that changes tmux

new-session -d -P -F LTM1-session-#{session_id} -s work -x 80 -y 24 -- 'exec cat' LTM1-session-$0

Before these, the library asked tmux about itself 4 times (its version, its daemon, how a control client reads escapes).

`Server.snapshot` returned `Snapshot`

{
  "panes": 1,
  "sessions": 1,
  "windows": 1
}

7 tmux commands

list-sessions -F 'LTM1\011libtmux.format/v1:session:session:qa:none:id,name,windows-count,attached-count,created,activity,path,grouped,group-name\011qa\011#{session_id}\011#{q/a:session_name}\011#{session_windows}\011#{session_attached}\011#{session_created}\011#{session_activity}\011#{q/a:session_path}\011#{session_grouped}\011#{q/a:session_group}\011END' LTM1 libtmux.format/v1:session:session:qa:none:id,name,windows-count,attached-count,created,activity,path,grouped,group-name qa $0 work 1 0 1794634589 1794634589 /tmp/marked 0 END
list-windows -a -F 'LTM1\011libtmux.format/v1:window-link:window-link:qa:none:session-id,window-id,index,active,last,activity,bell,silence\011qa\011#{session_id}\011#{window_id}\011#{window_index}\011#{window_active}\011#{window_last_flag}\011#{window_activity_flag}\011#{window_bell_flag}\011#{window_silence_flag}\011END' LTM1 libtmux.format/v1:window-link:window-link:qa:none:session-id,window-id,index,active,last,activity,bell,silence qa $0 @0 0 1 0 0 0 0 END
list-windows -a -F 'LTM1\011libtmux.format/v1:window:window:qa:none:id,name,width,height,panes-count,layout,visible-layout,zoomed,modal-pane-id\011qa\011#{window_id}\011#{q/a:window_name}\011#{window_width}\011#{window_height}\011#{window_panes}\011#{q/a:window_layout}\011#{q/a:window_visible_layout}\011#{window_zoomed_flag}\011#{window_modal_pane}\011END' LTM1 libtmux.format/v1:window:window:qa:none:id,name,width,height,panes-count,layout,visible-layout,zoomed,modal-pane-id qa @0 sh 80 24 1 "{\"V\":2,\"L\":{\"t\":\"p\",\"w\":80,\"h\":24,\"x\":0,\"y\":0,\"a\":true,\"i\":0,\"I\":\"%0\"}}" "{\"V\":2,\"L\":{\"t\":\"p\",\"w\":80,\"h\":24,\"x\":0,\"y\":0,\"a\":true,\"i\":0,\"I\":\"%0\"}}" 0 END
list-panes -a -F 'LTM1\011libtmux.format/v1:pane:pane:qa:none:id,window-id,index,active,width,height,left,top,pid,tty,title,current-command,current-path,start-command,start-path,dead,dead-status,dead-signal,dead-time,in-mode,mode,pipe,synchronized,floating,modal,x,y,z,command-running,command-status,at-top,at-bottom,at-left,at-right\011qa\011#{pane_id}\011#{window_id}\011#{pane_index}\011#{pane_act… LTM1 libtmux.format/v1:pane:pane:qa:none:id,window-id,index,active,width,height,left,top,pid,tty,title,current-command,current-path,start-command,start-path,dead,dead-status,dead-signal,dead-time,in-mode,mode,pipe,synchronized,floating,modal,x,y,z,command-running,command-status,at-top,at-bottom,at-left,at-right qa %0 @0 0 1 80 24 0 0 2005202 /dev/pts/19 host cat /tmp/marked "\"exe…
list-clients -F 'LTM1\011libtmux.format/v1:client:client:qa:none:name,session-id,session-name,tty,pid,width,height,created,activity,control-mode,read-only,terminal-name,key-table\011qa\011#{q/a:client_name}\011#{session_id}\011#{q/a:client_session}\011#{q/a:client_tty}\011#{client_pid}\011#{client_width}\011#{client_height}\011#{client_created}\011#{client_activity}\011#{client_control_mode}\011#{… no output
list-sessions -f #{session_grouped} -F 'LTM1\011libtmux.format/v1:session-group:grouped-session:qa:none:name,size,attached-count\011qa\011#{q/a:session_group}\011#{session_group_size}\011#{session_group_attached}\011END' no output
list-buffers -F 'LTM1\011libtmux.format/v1:buffer:buffer:qa:none:name,size,created,sample\011qa\011#{q/a:buffer_name}\011#{buffer_size}\011#{buffer_created}\011#{q/a:buffer_sample}\011END' no output

Before these, the library asked tmux about itself 6 times (its version, its daemon, how a control client reads escapes).

`PaneSelection.single` returned `PaneRef`

{
  "id": "%0"
}

The call sent no tmux command.

`PaneRef.split` returned `PaneRef`

{
  "id": "%1"
}

1 tmux command, 1 that changes tmux

split-window -P -F LTM1-pane-#{pane_id} -t %0 -h -d -- 'exec cat' LTM1-pane-%1

`PaneRef.set-title` returned `void`

null

1 tmux command, 1 that changes tmux

select-pane -t %0 -T editor no output

`PaneRef.set-title` returned `void`

null

1 tmux command, 1 that changes tmux

select-pane -t %1 -T logs no output

`Server.snapshot` returned `Snapshot`

{
  "panes": 2,
  "sessions": 1,
  "windows": 1
}

7 tmux commands

list-sessions -F 'LTM1\011libtmux.format/v1:session:session:qa:none:id,name,windows-count,attached-count,created,activity,path,grouped,group-name\011qa\011#{session_id}\011#{q/a:session_name}\011#{session_windows}\011#{session_attached}\011#{session_created}\011#{session_activity}\011#{q/a:session_path}\011#{session_grouped}\011#{q/a:session_group}\011END' LTM1 libtmux.format/v1:session:session:qa:none:id,name,windows-count,attached-count,created,activity,path,grouped,group-name qa $0 work 1 0 1794634589 1794634589 /tmp/marked 0 END
list-windows -a -F 'LTM1\011libtmux.format/v1:window-link:window-link:qa:none:session-id,window-id,index,active,last,activity,bell,silence\011qa\011#{session_id}\011#{window_id}\011#{window_index}\011#{window_active}\011#{window_last_flag}\011#{window_activity_flag}\011#{window_bell_flag}\011#{window_silence_flag}\011END' LTM1 libtmux.format/v1:window-link:window-link:qa:none:session-id,window-id,index,active,last,activity,bell,silence qa $0 @0 0 1 0 0 0 0 END
list-windows -a -F 'LTM1\011libtmux.format/v1:window:window:qa:none:id,name,width,height,panes-count,layout,visible-layout,zoomed,modal-pane-id\011qa\011#{window_id}\011#{q/a:window_name}\011#{window_width}\011#{window_height}\011#{window_panes}\011#{q/a:window_layout}\011#{q/a:window_visible_layout}\011#{window_zoomed_flag}\011#{window_modal_pane}\011END' LTM1 libtmux.format/v1:window:window:qa:none:id,name,width,height,panes-count,layout,visible-layout,zoomed,modal-pane-id qa @0 sh 80 24 2 "{\"V\":2,\"L\":{\"t\":\"h\",\"w\":80,\"h\":24,\"x\":0,\"y\":0,\"c\":[{\"t\":\"p\",\"w\":40,\"h\":24,\"x\":0,\"y\":0,\"a\":true,\"i\":0,\"I\":\"%0\"},{\"t\":\"p\",\"w\":39,\"h\":24,\"x\":41,\"y\":0,\"i\":1,\"I\":\"%1\"}]}}" "{\"V\":2,\"L\":{\"t\":\"h\",\"w\":80,…
list-panes -a -F 'LTM1\011libtmux.format/v1:pane:pane:qa:none:id,window-id,index,active,width,height,left,top,pid,tty,title,current-command,current-path,start-command,start-path,dead,dead-status,dead-signal,dead-time,in-mode,mode,pipe,synchronized,floating,modal,x,y,z,command-running,command-status,at-top,at-bottom,at-left,at-right\011qa\011#{pane_id}\011#{window_id}\011#{pane_index}\011#{pane_act… LTM1 libtmux.format/v1:pane:pane:qa:none:id,window-id,index,active,width,height,left,top,pid,tty,title,current-command,current-path,start-command,start-path,dead,dead-status,dead-signal,dead-time,in-mode,mode,pipe,synchronized,floating,modal,x,y,z,command-running,command-status,at-top,at-bottom,at-left,at-right qa %0 @0 0 1 40 24 0 0 2005202 /dev/pts/19 editor cat /tmp/marked "…
list-clients -F 'LTM1\011libtmux.format/v1:client:client:qa:none:name,session-id,session-name,tty,pid,width,height,created,activity,control-mode,read-only,terminal-name,key-table\011qa\011#{q/a:client_name}\011#{session_id}\011#{q/a:client_session}\011#{q/a:client_tty}\011#{client_pid}\011#{client_width}\011#{client_height}\011#{client_created}\011#{client_activity}\011#{client_control_mode}\011#{… no output
list-sessions -f #{session_grouped} -F 'LTM1\011libtmux.format/v1:session-group:grouped-session:qa:none:name,size,attached-count\011qa\011#{q/a:session_group}\011#{session_group_size}\011#{session_group_attached}\011END' no output
list-buffers -F 'LTM1\011libtmux.format/v1:buffer:buffer:qa:none:name,size,created,sample\011qa\011#{q/a:buffer_name}\011#{buffer_size}\011#{buffer_created}\011#{q/a:buffer_sample}\011END' no output

Before these, the library asked tmux about itself 6 times (its version, its daemon, how a control client reads escapes).

`PaneSelection.single` returned `Pane`

{
  "id": "%0",
  "title": "editor"
}

The call sent no tmux command.

`Server.close` returned `void`

null

The call sent no tmux command.

0/9

Run this example

Linux, Raku 6.d with zef, and tmux 3.3a through 3.8 on PATH. The first command installs the published LibTmux distribution from Raku Land, so it needs network access to the zef ecosystem. The program starts its own private tmux server.

Save the program above as quickstart.raku in a new directory, along with the files below.

This complete program owns a private tmux server and closes it with LEAVE when the program exits, including on an exception.

Setup and run

zef install 'LibTmux:ver<0.0.1+>:auth<zef:libtmux>'

raku quickstart.raku

Expected output

editor: 2 panes

Typed API

Typed objects instead of parsed format strings: LibTmux::Model::Pane
Addressing by tmux ID: LibTmux::Model::Pane.id
Filtering and queries over tmux objects: LibTmux::Model::PaneSelection.where
Typed errors instead of exit codes and stderr: X::LibTmux::InvalidFilter

What you get over the tmux CLI

Connect to or start a tmux server: LibTmux::Server.start
Traversal from a server down to its panes: LibTmux::Server.snapshot
Send keys to a pane: LibTmux::Model::PaneRef.send-keys
Watch for changes through tmux control mode: LibTmux::Server.open-control-async
Capture pane contents: LibTmux::Model::PaneRef.capture
Arguments passed as a list, with no shell quoting: LibTmux::Server.command
A typed error when the running tmux lacks a feature: X::LibTmux::Unsupported
Async operations: LibTmux::Server.snapshot-async

LibTmux gives Raku programs typed snapshots of a tmux server, ordinary predicates over them, and explicit commands that change tmux. Reading a snapshot makes no further tmux calls; an operation through a reference does.

The LibTmux distribution from the zef:libtmux authority is published on Raku Land. Its API is experimental and may change between 0.x releases. CI qualifies Rakudo 2026.09 on Linux with tmux 3.3a and 3.8; other platforms and compiler versions are unverified. The library has no workspace manager or MCP server.

Scripting & web

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tmux

tmux client library for Raku

Getting started

Examples

tmux compatibility

API reference

Install

At a glance

What it does

Before the first call

`Server.start` returned `Server`

`Server.snapshot` returned `Snapshot`

`PaneSelection.single` returned `PaneRef`

`PaneRef.split` returned `PaneRef`

`PaneRef.set-title` returned `void`

`PaneRef.set-title` returned `void`

`Server.snapshot` returned `Snapshot`

`PaneSelection.single` returned `Pane`

`Server.close` returned `void`

Setup and run

Expected output

Typed API

What you get over the tmux CLI

tmux client library for Raku

Getting started

Examples

tmux compatibility

API reference

Install

At a glance

What it does

Before the first call

Server.start returned Server

Server.snapshot returned Snapshot

PaneSelection.single returned PaneRef

PaneRef.split returned PaneRef

PaneRef.set-title returned void

PaneRef.set-title returned void

Server.snapshot returned Snapshot

PaneSelection.single returned Pane

Server.close returned void

Setup and run

Expected output

Typed API

What you get over the tmux CLI

`Server.start` returned `Server`

`Server.snapshot` returned `Snapshot`

`PaneSelection.single` returned `PaneRef`

`PaneRef.split` returned `PaneRef`

`PaneRef.set-title` returned `void`

`PaneRef.set-title` returned `void`

`Server.snapshot` returned `Snapshot`

`PaneSelection.single` returned `Pane`

`Server.close` returned `void`