netspd

A beautiful, modern network speed test for your terminal — with a hypercar tachometer.

netspd measures ping, jitter, download and upload against LibreSpeed-compatible servers and renders them live on a braille-canvas instrument cluster: a spring-loaded needle with an ignition sweep, a heat-gradient band that reddens toward the hatched redline, a session-peak ghost notch, and a latency sub-dial — in the spirit of tools like btop, gitui and lazygit.

Features

• Hypercar tachometer — heat-gradient value band, hatched redline, spring-physics needle with afterglow, ignition sweep before each phase, peak ghost notch, latency sub-dial; twin instrument cluster on wide terminals
• Live metrics — current / average / peak speed, transferred bytes, ETA, elapsed time
• Latency analysis — multiple samples, outlier trimming, jitter, real ICMP packet loss (graceful fallback where ICMP is unavailable)
• Smart server discovery — health-probes the public server list, drops dead servers, auto-selects the nearest
• Headless mode — --no-tui for scripts and cron, --json for machine-readable reports
• Result history — every run appended as JSON lines to your data directory
• Streaming transfers — nothing buffered in memory; parallel connections with EMA smoothing
• Themes — Default, Nord, Dracula, Catppuccin, Gruvbox, plus your own TOML themes without recompiling
• Responsive layout — adapts from 80×24 up to 4K terminals
• Graceful everywhere — cancellation, retries, timeouts; network failures never panic

Installation

Homebrew (macOS / Linux)

brew tap TarunVishwakarma1/tap
brew install netspd

Prebuilt binaries

Download the archive for your platform from the latest release, unpack it and put netspd on your PATH.

From source

git clone https://github.com/TarunVishwakarma1/netspd
cd netspd
cargo install --path .

Requires Rust 1.88 or newer.

Usage

netspd                     # full TUI
netspd --no-tui            # headless: progress on stderr, summary on stdout
netspd --json              # headless: report as one JSON object on stdout
netspd --list-servers      # print reachable servers, nearest first
netspd -s tokyo            # pick a server by name/host substring
netspd -d 5 -c 8           # 5-second phases over 8 connections

The test starts automatically: ping → download → upload, then a results summary. If a server fails mid-test, netspd automatically retries with the next-nearest one (unless you pinned a server with --server).

Keyboard

Scripting

--json prints exactly one JSON object on stdout and nothing else, so it pipes cleanly:

netspd --json | jq .download_mbps

{
  "timestamp": 1783092092,
  "server": "Tokyo, Japan (A573)",
  "ping_ms": 141.2,
  "jitter_ms": 1.0,
  "packet_loss_pct": 0.0,
  "download_mbps": 93.7,
  "download_peak_mbps": 171.0,
  "download_bytes": 117193129,
  "upload_mbps": 66.3,
  "upload_peak_mbps": 87.8,
  "upload_bytes": 82837504
}

Exit code is 0 on a completed test and 1 on any failure. Every completed run (TUI or headless) is also appended to <data dir>/netspd/history.jsonl (macOS: ~/Library/Application Support/netspd/, Linux: ~/.local/share/netspd/), one JSON object per line.

Configuration

netspd reads the first config.toml found in:

1. $XDG_CONFIG_HOME/netspd/config.toml (macOS: ~/Library/Application Support/netspd/config.toml)
2. ./config/config.toml

Every key is optional; see config/config.toml for the annotated reference. Highlights:

theme = "catppuccin"       # default | nord | dracula | catppuccin | gruvbox
refresh_rate = 30          # UI frames per second (1..=60)
provider = "librespeed"
animation_speed = 1.0

[engine]
duration_secs = 10         # length of each transfer phase
connections = 4            # parallel connections
ping_samples = 10

[[servers]]                # optional: pin your own backend
name = "My Server"
url = "https://speedtest.example.com/backend/"

Custom themes go in ~/.config/netspd/themes/*.toml — copy any file from assets/themes/ as a starting point.

Architecture

netspd follows clean architecture with strict one-way dependencies:

┌──────────────────────────────────────────────┐
│ tui/          presentation (Ratatui only)    │
│   theme · animation · widgets · screens      │
├──────────────────────────────────────────────┤
│ app/          application                    │
│   events → controller → state → renderer    │
├──────────────────────────────────────────────┤
│ engine/       domain (no UI imports)         │
│   Engine → scheduler → providers/network     │
│   metrics: EMA · sampler · throughput ·      │
│            latency · statistics              │
├──────────────────────────────────────────────┤
│ config/ · errors/ · utils/   infrastructure  │
└──────────────────────────────────────────────┘

• The engine emits strongly-typed EngineEvents over a channel and never imports Ratatui — it is directly reusable from a CLI, GUI, REST API or as a library.
• Providers implement one trait (Provider); adding a new speed test network touches nothing else.
• State is plain data mutated only by reducers; the renderer just draws it.
• Metrics are pure, deterministic calculators, each independently unit-tested.

Development

cargo test            # unit + integration tests
cargo clippy          # lint-clean, unwrap/expect/panic denied
cargo fmt --check

See CONTRIBUTING.md for the layering rules and PR checklist.

Roadmap

• JSON result export and --no-tui CLI mode
• Result history (JSON lines)
• Trend sparklines over the stored history (g)
• --server, --list-servers, --duration, --connections flags
• Automatic failover to the next server on failure
• Packet loss via ICMP echo probing
• Homebrew tap
• Ookla and Fast.com providers
• Scheduled repeat testing

License

MIT