A Kubernetes TUI written in Rust, inspired by k9s.

Browse and manage Kubernetes resources (pods, deployments, services, nodes, CRDs, etc.)

Real-time streaming with automatic refresh

Describe, YAML view, edit, delete, scale, restart, port-forward, shell

Log streaming with filtering, timestamps, wrap mode and horizontal panning

Drill-down navigation (deployment → pods → containers → logs)

Context and namespace switching

k9s-compatible skin/theme support

User-defined overlays (custom columns, coloring rules, key bindings)

Configurable TUI preferences and daemon tuning

Architecture

k9rs uses a client/daemon architecture:

The TUI never talks to the Kubernetes cluster directly. All data flows through the daemon via a binary protocol (length-prefixed bincode over yamux-multiplexed Unix socket).

cargo build --release cp target/release/k9rs ~/.local/bin/

Usage

k9rs # start with overview k9rs pods # start on pods k9rs -n kube-system # start in a specific namespace k9rs --context prod # start with a specific context k9rs --readonly # read-only mode (no mutations)

Key Bindings

Press ? in any view for the full keybinding table — a filterable, sortable view of the keys for the view you pressed it in. Key highlights:

Resource-specific keys (shown in ? help when available):

Marking rows with Space enters select mode: single-row keys go dead, and Ctrl-d / r / Ctrl-k act on ALL marked rows (with a confirm dialog listing the targets). Ctrl-\ clears the selection.

k9rs: noExitOnCtrlC: false # Ctrl-C quits (it is a key, not a signal —

the TUI runs in raw mode)

readOnly: false # refuse every mutation client-side as well as

server-side

Key rebindings. An operation entry MOVES that operation's binding (its

default key stops working) — except for delete, forceKill and portForward,

whose real chords (Ctrl-D / Ctrl-K / Shift-F) are structural, so rebinding

those ADDS a second key rather than moving the first. The col* entries ADD

chords for column

movement (arrows always work) and win over an operation bound to the

same key. In a LOG view the same col* chords pan horizontally — one

"move left/right in this view" intent, answered by each view in its own

units. Chords: "x", "X", or "ctrl-x".

Rebindable operations: describe, yaml, logs, previousLogs, shell,

restart, scale, delete, forceKill, portForward, showNode, nodeShell,

decodeSecret, triggerCronJob, toggleSuspendCronJob.

keys: colLeft: h # vim-style column movement … colRight: l colFirst: "0" # … and jumps to the first / last column colLast: "$" # (in a log view: the pan margins) namespaceAll: ")" # rebind all-namespaces, freeing 0 logs: ctrl-l # … freed by moving logs off plain l

TUI preferences

ui: theme: auto # auto | dark | light — auto asks the

terminal for its background colour and

falls back to dark. --theme <mode>

overrides this for one run.

skin: dracula # skin name (loads from skins/ directory);

layers on top of the chosen theme

maxColumnWidth: 64 # max column width before truncation commandHistorySize: 50 # max : command history entries changeHighlightSecs: 5 # row change highlight duration cacheCapacity: 100 # describe/yaml cache entries searchContextLines: 10 # lines above search match flash: infoSecs: 3 # info message duration warnSecs: 5 # warning message duration errorSecs: 10 # error message duration logs: maxLines: 50000 # log buffer size tailLines: 100 # lines fetched on log open defaultFollow: true # auto-scroll logs defaultWrap: false # wrap long lines (w) defaultFields: source # per-line fields to start on; t cycles them.

all = timestamp + source tag + message

source = source tag + message

message = message only

Daemon tuning

daemon: watcherPageSize: 1000 # K8s LIST pagination batch discoveryRefreshSecs: 300 # CRD/namespace discovery poll interval fanoutRing: 64 # delta batches buffered per watcher watcherGraceSecs: 60 # keep a watcher warm this long after the last viewer leaves localsGraceSecs: 1800 # keep a context's PORT-FORWARDS alive this long after its

last session detaches. Deliberately much longer than

watcherGraceSecs: a warm watcher is a cache (costs a row

store + an apiserver watch, buys back a re-LIST), whereas a

port-forward is something you asked for and would have to

notice dying and recreate.

backoff: initialMs: 300 # watcher retry start maxMs: 30000 # max single retry sleep maxElapsedMs: 120000 # total retry timeout execResources: # user-defined local resources backed by commands

• name: pod-metrics # unique name (navigate via :pod-metrics) command: kubectl args: ["top", "pods", "-A", "--no-headers"] headers: ["NAMESPACE", "NAME", "CPU", "MEMORY"] jsonFieldKeys: [] # empty = raw TSV parsing pollIntervalSecs: 30

All fields are optional — omitting them uses the defaults shown above. Typos in field names produce an error (strict validation via deny_unknown_fields).

User-defined resource customizations. Place YAML files in ~/.config/k9rs/overlays/.

~/.config/k9rs/overlays/nodeclaims.yaml

resource: nodeclaims

Named capabilities with typed implementations

capabilities: show-node: type: drill target: nodes column: NODE

Key → capability name bindings

bindings: o: show-node

Extra columns (JSONPath for CRDs, level override for built-ins)

columns:

• header: "INSTANCE TYPE" jsonpath: ".spec.instanceType"
• header: "NODE" jsonpath: ".status.nodeName"

Declarative coloring rules

coloring:

• column: "STATUS" rules:
• match: "NotReady" health: failed
• match: "Pending" health: pending
• column: "CPU%" rules:
• when: ">= 90" health: failed
• when: ">= 70" health: pending

Overlay Features

Coloring rules — map cell values to row health (Normal/Pending/Failed → green/yellow/red). Works for both CRDs and built-in resources.

Extra columns — JSONPath extraction for CRDs. For built-in resources, use level: default to promote existing extra columns to default visibility.

Key bindings — bind keys to named capabilities. Built-in keys can't be shadowed. Capabilities define the implementation (e.g., drill to another resource filtered by a column value).

k9s-compatible skin files. Place in ~/.config/k9rs/skins/ and reference by name in config.

~/.config/k9rs/config.yaml

k9rs: ui: skin: dracula

The skin file format matches k9s skin YAML.