K U L A

Lightweight, self-contained Linux® server monitoring tool.

🌏 Website | 👀 Demo | 🐋 Docker Hub

Zero dependencies. No external databases. Single binary. Just deploy and go.

📦 What It Does

Kula collects system metrics every second by reading directly from /proc and /sys, stores them in a built-in tiered ring-buffer storage engine, and serves them through a real-time Web UI dashboard and a terminal TUI.

Note: Monitoring NVIDIA GPUs might require additional setup. Check GPU monitoring.

🪩 How It Works

    ╭──────────────────────────────────────────────╮
    │                  Linux Kernel                │
    │      /proc/stat  /proc/meminfo  /sys/...     │
    ╰───────────────────────┬──────────────────────╯
                            │ Read every 1s
                            ▼
    ╭──────────────────────────────────────────────╮
    │                   Collectors                 │
    │        (CPU, Mem, Net, Disk, System)         │
    ╰───────────────────────┬──────────────────────╯
                            │ Live Data
         ╭──────────────────┼─────────────────────╮
         ▼                  ▼                     ▼
╭─────────────────╮  ╭────────────────╮  ╭─────────────────╮
│ Storage Engine  │  │   Web Server   │  │   TUI Terminal  │
╰───┬─────────┬───╯  ╰──────┬─────────╯  ╰─────────────────╯
    │         │             │
    │         ╰──(History)──┤              ╭───────────────╮
    │                       ╰──(HTTP/WS)─► |   Dashboard   |
    ▼                                      ╰───────────────╯
╭──────────┬──────────┬──────────╮
│  Tier 1  │  Tier 2  │  Tier 3  │
│    1s    │    1m    │    5m    │
│  250 MB  │  150 MB  │  50 MB   │
╰──────────┴──────────┴──────────╯
 Ring-buffer binary files
 with circular overwrites

Storage Engine

Kula is powered by a custom-built, high-performance ring-buffer storage system that writes metrics directly into fixed-size binary files. Because the files have a strict maximum capacity, new data seamlessly wraps around to overwrite the oldest entries. On startup, Kula restores the latest-sample cache and reconstructs any pending aggregation buffers so it can resume serving recent data and continue tier rollups after a restart.

To maximize efficiency, Kula employs a multi-tiered architecture that intelligently downsamples older data:

• Tier 1 — Raw 1-second samples (default 250 MB)
• Tier 2 — 1-minute metrics aggregation (Avg/Min/Max) (default 150 MB)
• Tier 3 — 5-minute metrics aggregation (Avg/Min/Max) (default 50 MB)

HTTP server

The HTTP server on backend exposes a REST API and a WebSocket endpoint for live streaming. Authentication is optional. When enabled, Kula uses Argon2id password hashing, secure session cookies, token-only session validation with sliding expiration, and hashed-at-rest session persistence. Authenticated API access can also use a bearer session token via the Authorization header.

Dashboard

The frontend is a single-page application embedded in the binary. Built on Chart.js with custom SVG gauges, it connects via WebSocket for live updates and falls back to history API for longer time ranges. Features include:

• Interactive zoom with drag-select (auto-pauses live stream)
• Focus mode to display only specific charts of interest
• Configurable Y-axis bounds (Manual limits or Auto-detect)
• Per-device selectors for Network, Disk I/O, and Thermal monitoring
• Grid / stacked list layout toggle
• Alert system for clock sync, low entropy, and system overload
• Modern aesthetics with light/dark theme support
• Optional AI assistant powered by a local Ollama model (see below)
• Prometheus exporter endpoint for scraping into existing observability stacks

AI Assistant

Kula features an AI assistant via Ollama.

When Ollama is enabled in config.yaml, a 🤖 button appears in the dashboard header. The panel supports:

• Multi-session conversations — open independent threads and switch between them
• Per-chart analysis — click the 🤖 icon on any chart card to open a session pre-loaded with that chart's recent data as CSV
• Agentic tool calling — the model can call get_metrics to pull metrics on demand (up to 5 rounds per turn)
• Model selector — switch between any locally available Ollama model mid-session
• Draggable & resizable panel — drag by the header, resize from the bottom-right grip
• Streaming responses with markdown rendering

All AI inference runs locally through Ollama API.

💾 Installation

Kula was built to have everything in one binary file. You can just upload it to your server and not worry about installing anything else because Kula has no dependencies. It just works out of the box! It is a great tool when you need to quickly start real-time monitoring.

Example installation methods for amd64 (x86_64) GNU/Linux.

Check Releases for ARM and RISC-V packages.

Note: Never thoughtlessly paste commands into the terminal. Even checking the checksum is no substitute for reviewing the code.

Guided

bash -c "$(curl -fsSL https://raw.githubusercontent.com/c0m4r/kula/refs/heads/main/addons/install_v2.sh)"

Guided (verify installer)

KULA_INSTALL=$(mktemp)
curl -o ${KULA_INSTALL} -fsSL https://raw.githubusercontent.com/c0m4r/kula/refs/heads/main/addons/install_v2.sh
echo "bad61ee9eed4595d20fa7e613bd27c3b8700c67f8a5fcac756d282a811705398 ${KULA_INSTALL}" | sha256sum -c || rm -f ${KULA_INSTALL}
bash ${KULA_INSTALL}
rm -f ${KULA_INSTALL}

Standalone

wget https://github.com/c0m4r/kula/releases/download/0.18.3/kula-0.18.3-amd64.tar.gz
echo "b1196aee70709215586f818e2ee377bfa1ceb5b182020579199898aa717e253b kula-0.18.3-amd64.tar.gz" | sha256sum -c || rm -f kula-0.18.3-amd64.tar.gz
tar -xvf kula-0.18.3-amd64.tar.gz
cd kula
./kula

Docker

Temporary, no persistent storage:

docker run --rm -it --name kula --pid host --network host -v /proc:/proc:ro c0m4r/kula:latest

With persistent storage:

docker run -d --name kula --pid host --network host -v /proc:/proc:ro -v kula_data:/app/data c0m4r/kula:latest
docker logs -f kula

Debian / Ubuntu (.deb)

wget https://github.com/c0m4r/kula/releases/download/0.18.3/kula-0.18.3-amd64.deb
echo "113d710916941a9d98e6b397ea323fc5ea61133d2485ae790d6d61edbb829b9c kula-0.18.3-amd64.deb" | sha256sum -c || rm -f kula-0.18.3-amd64.deb
sudo dpkg -i kula-0.18.3-amd64.deb
journalctl -f -t kula

RHEL / Fedora / CentOS / Rocky / Alma (.rpm)

wget https://github.com/c0m4r/kula/releases/download/0.18.3/kula-0.18.3-x86_64.rpm
echo "fcbab15bcab9fe097fde89332772c322105379549caff9c7e6fbd3883f2520de kula-0.18.3-x86_64.rpm" | sha256sum -c || rm -f kula-0.18.3-x86_64.rpm
sudo rpm -i kula-0.18.3-x86_64.rpm
journalctl -f -t kula

Arch Linux / Manjaro (AUR)

https://aur.archlinux.org/packages/kula

git clone https://aur.archlinux.org/kula.git
cd kula
makepkg -si

Snap

sudo snap install kula

The snap uses strict sandbox so by default Kula features will be limited to the basics, which can be extended with snap connect.

See Snap Wiki for the full guide.

Build from Source

git clone https://github.com/c0m4r/kula.git
cd kula
./addons/build.sh

💻 Usage

Quick Start

Starting Kula is as simple as running:

./kula

Dashboard will be available at: http://localhost:27960 (or :8080 if you're using earlier versions)

You can change default port and listen address in config.yaml or using environment variables:

export KULA_LISTEN="127.0.0.1"
export KULA_PORT="27960"
./kula

TUI

./kula tui

Inspect storage

./kula inspect

Prometheus metrics

See: Prometheus metrics for more info.

Health endpoints

Kula exposes lightweight liveness endpoints at:

http://localhost:27960/health
http://localhost:27960/status

Both return:

200 OK
kula is healthy

Authentication (Optional)

# Generate password hash
./kula hash-password

# Add the output to config.yaml under web.auth

When authentication is enabled, Kula issues a random session token after login, stores only its hash on disk, and validates requests by token expiry/validity rather than binding sessions to client IP or User-Agent.

Service Management

Init system files are provided in addons/init/:

# systemd
sudo cp addons/init/systemd/kula.service /etc/systemd/system/
sudo systemctl enable --now kula

# OpenRC
sudo cp addons/init/openrc/kula /etc/init.d/
sudo rc-update add kula default

# runit
sudo cp -r addons/init/runit/kula /etc/sv/
sudo ln -s /etc/sv/kula /var/service/

⚙️ Configuration

All settings live in config.yaml. See config.example.yaml for defaults.

🧰 Development

# Lint + test suite
./addons/check.sh

# Build
./addonsh.build.sh

# Build dev (Binary size: ~20MB)
CGO_ENABLED=0 go build -o kula ./cmd/kula/

# Build prod (Binary size: ~14MB, xz: ~4MB)
CGO_ENABLED=0 go build -trimpath -ldflags="-s -w" -buildvcs=false -o kula ./cmd/kula/

Updating Dependencies

To safely update only the Go modules used by Kula to their latest minor/patch versions, and prune any unused dependencies:

./addons/go_modules_updates.py
go get -u ./...
go mod tidy

Testing & Benchmarks

# Run unit tests with race detector
go test -race ./...

# Run the full storage benchmark suite (default: 3s per bench)
./addons/benchmark.sh

# Python scripts formatter and linters
black addons/*.py
pylint addons/*.py
mypy --strict addons/*.py

Cross-Compile

./addons/build.sh cross    # builds amd64, arm64, riscv64

Debian / Ubuntu (.deb)

./addons/build_deb.sh
ls -1 dist/kula-*.deb

Arch Linux / Manjaro (AUR)

./addons/build_aur.sh
cd dist/aur && makepkg -si

RHEL / Fedora / CentOS / Rocky / Alma (.rpm)

./addons/build_rpm.sh
ls -1 dist/kula-*.rpm

Docker

./addons/docker/build.sh
docker compose -f addons/docker/docker-compose.yml up -d

Snap

Requires snapcraft and a build backend (LXD recommended):

snap install snapcraft --classic
snap install lxd
lxd init --auto
./addons/build_snap.sh            # host arch, into dist/
./addons/build_snap.sh cross      # cross-build amd64/arm64/riscv64 locally
ls -1 dist/kula-*.snap

🔒 Privacy

Privacy is a core pillar, not an afterthought.

Kula is built for privacy-conscious infrastructure. It is a completely self-contained binary that requires no cloud connection and no third-party APIs. Designed to function perfectly in air-gapped networks, Kula never sends metadata to external servers, never serves advertisements, and requires no user registration. Your monitoring starts and ends on your infrastructure, exactly where it should be.

📖 License

GNU Affero General Public License v3.0

🫶 Attributions

• Linux® is the registered trademark of Linus Torvalds in the U.S. and other countries.
• Chart.js library licensed under MIT
• Inter font by Rasmus Andersson licensed under OFL-1.1
• Press Start 2P font by CodeMan38 licensed under OFL-1.1