Resterm

A terminal API client for REST, GraphQL, gRPC, WebSocket and SSE.

Resterm is a keyboard-driven API client that runs in your terminal. Requests are plain .http files that you can diff, review and version like code. Everything stays on your machine. No accounts, no cloud sync, no telemetry.

Quick links: Screenshots, Installation, Quick Start, Documentation.

Screenshot tour

Why Resterm

• HTTP, GraphQL, gRPC, WebSocket and SSE out of the box.
• Automation lives in the request files: conditions (@when, @if/@elif/@else, @for-each), multi-step workflows (@workflow / @step), captures, variables and assertions (@capture, @var, @assert).
• RestermScript, a small expression language built for Resterm, with JavaScript hooks when you want them.
• Vim-style controls with familiar motions, / search and commands like :w, :q, :e and :help.
• Built-in auth and tunneling: OAuth 2.0 (client credentials, password, auth code with PKCE), auth backed by your existing CLIs, SSH tunnels and Kubernetes port-forwards. No extra tools needed.
• CLI runner: resterm run for scripted runs and CI, with JSON and JUnit output.
• Mock servers declared next to the requests they mimic, with matching rules, sequences, call verification and hot reload.
• Timeline tracing, profiling and compare runs across environments.
• Streaming transcripts and an interactive console for WebSocket and SSE.
• No AI integration, ever.

CLI

Use resterm run to execute .http / .rest files without opening the TUI.

mkdir my-api && cd my-api
resterm init
resterm run --request Echo requests.http

resterm init creates requests.http with sample requests and resterm.env.json with a dev environment pointing at httpbin.org. The last command runs the Echo request, which POSTs a JSON body and prints the response.

The CLI documentation covers selectors, output formats and more examples.

Mock Servers

The same files that hold your requests can serve HTTP mocks.

• Match incoming requests by query, headers or JSON body, then pick a named or default response.
• Model polling and retry flows with response sequences, including independent cursors per resource or caller.
• Build responses from path, query, header and body values, with generators for dynamic data.
• Verify call counts with @expect or inspect received traffic from RestermScript.
• Hot reload source files and fixtures, with optional TLS.

Two scenarios on one route:

### Payment accepted
# @mock method=POST path=/payments name=accepted default=true latency=150ms
HTTP/1.1 202 Accepted
Content-Type: application/json

{"id":"pay_123","status":"pending"}

### Payment declined
# @mock method=POST path=/payments name=declined
# @match query={"mode":"decline"} headers={"X-Tenant":"demo"} json={"amount":0}
HTTP/1.1 422 Unprocessable Entity
Content-Type: application/json

{"error":"amount must be positive"}

Serve one file or a whole directory:

resterm mock ./requests.http
resterm mock --recursive --addr 127.0.0.1:9090 ./requests

More in the Mock Servers reference, the resterm mock CLI guide and the working example.

Headless

The headless package is the public Go API for the same engine that powers the TUI and CLI. Use it to run requests, workflows, assertions, compare runs and profiles from your own Go code or CI.

If you would rather not build a runner yourself, there is resterm-runner.

Quick Start

1. Install Resterm (see Installation for scripts, Windows and manual installs).

   brew install resterm
   

2. Bootstrap a workspace.

   mkdir my-api && cd my-api
   resterm init
   

3. Start it and send your first request.

   resterm
   

   Press Ctrl+Enter in the editor to send the highlighted request.

No files yet? Just run resterm, type a URL and press Ctrl+Enter. A pasted curl command works too.

Keyboard cheat sheet

• Pane focus and layout
  • Tab / Shift+Tab: move between sidebar, editor and response.
  • g+r, g+i, g+p: jump to requests, editor or response.
  • g+h / g+l: resize horizontally. Changes sidebar width when the sidebar is focused, the editor/response split otherwise.
  • g+j / g+k: resize editor/response height when stacked, collapse or expand branches in the navigator.
  • g+v / g+s: toggle the response pane between inline and stacked layout.
  • g+1, g+2, g+3: minimize or restore sidebar, editor, response.
  • g+z / g+Z: zoom the focused pane, clear zoom.
• Environments and globals
  • Ctrl+E: switch environments.
  • Ctrl+G: inspect captured globals.
• Responses
  • Ctrl+V / Ctrl+U: split the response pane for side-by-side comparison.
  • Ctrl+Shift+C or g y (response focused): copy the whole Pretty, Raw or Headers tab.
  • g x: show the Explain preview for the active request without sending it.
  • g e: open the current file in your external editor.

[!TIP] If you only remember three shortcuts:

• Ctrl+Enter sends the request
• Tab / Shift+Tab switches panes
• g+p jumps to the response

Installation

Linux / macOS (Homebrew)

brew install resterm

[!NOTE] Homebrew installs should be updated with Homebrew (brew upgrade resterm). The built-in resterm --update command is for binaries installed from GitHub releases or install scripts.

Linux / macOS (Shell script)

[!IMPORTANT] Pre-built Linux binaries depend on glibc 2.32 or newer. On an older distro, build from source with a newer glibc toolchain or upgrade glibc before using the release archives.

curl -fsSL https://raw.githubusercontent.com/unkn0wn-root/resterm/main/install.sh | bash

or with wget:

wget -qO- https://raw.githubusercontent.com/unkn0wn-root/resterm/main/install.sh | bash

Windows (PowerShell)

iwr -useb https://raw.githubusercontent.com/unkn0wn-root/resterm/main/install.ps1 | iex

The scripts detect your architecture, download the latest release and install the binary.

Manual installation

[!NOTE] The manual install helper uses curl and jq. Install jq with your package manager (brew install jq, sudo apt install jq, etc.).

Linux / macOS

# Detect latest tag
LATEST_TAG=$(curl -fsSL https://api.github.com/repos/unkn0wn-root/resterm/releases/latest | jq -r .tag_name)

# Download the matching binary (Darwin/Linux + amd64/arm64)
curl -fL -o resterm "https://github.com/unkn0wn-root/resterm/releases/download/${LATEST_TAG}/resterm_$(uname -s)_$(uname -m)"

# Make it executable and move it onto your PATH
chmod +x resterm
sudo install -m 0755 resterm /usr/local/bin/resterm

Windows (PowerShell)

$latest = Invoke-RestMethod https://api.github.com/repos/unkn0wn-root/resterm/releases/latest
$asset  = $latest.assets | Where-Object { $_.name -like 'resterm_Windows_*' } | Select-Object -First 1
Invoke-WebRequest -Uri $asset.browser_download_url -OutFile resterm.exe
# Optionally relocate to a directory on PATH, e.g.:
Move-Item resterm.exe "$env:USERPROFILE\bin\resterm.exe"

From source

go install github.com/unkn0wn-root/resterm/cmd/resterm@latest

Update

resterm --check-update
resterm --update

The first command reports whether a newer release is available. The second downloads, verifies and installs it in place. On Windows the old binary stays next to the new one as resterm.exe.old and is cleaned up on the next update.

Configuration

• Environments are JSON files (resterm.env.json) discovered in the request directory, workspace root or CWD. Dotenv files (.env, .env.*) are opt-in via --env-file and are single-workspace. Prefer JSON when one file should hold several environments.
• Config is stored per OS and can be overridden with RESTERM_CONFIG_DIR:
  • macOS: ~/Library/Application Support/resterm
  • Windows: %APPDATA%\resterm
  • Linux/Unix: ~/.config/resterm

Collections

Export a workspace as a Git-friendly bundle and import it into another one. Bundles carry a manifest.json with checksums, so imports verify file integrity first. Environment values are exported as REPLACE_ME placeholders, so secrets never leave your machine.

resterm collection export --workspace ./my-api --out ./shared/my-api-bundle
resterm collection import --in ./shared/my-api-bundle --workspace ./my-local-api

Add --dry-run to preview an import and --force to overwrite existing files. Docs: collection sharing.

Curl import

Paste a curl command into the editor and press Ctrl+Enter to turn it into a structured request. Resterm understands the common flags, merges repeated data segments and keeps multipart uploads intact. Shell prefixes like sudo or $ are ignored. The CLI does the same conversion with --from-curl.

This:

curl -X POST https://api.example.com/login \
  -H "Content-Type: application/json" \
  --user demo:secret \
  -d '{"user":"demo"}'

becomes this:

### POST https://api.example.com/login
# @auth basic demo secret
POST https://api.example.com/login
Content-Type: application/json

{"user":"demo"}

Docs: inline requests and import examples.

RestermScript

RestermScript (RTS) is a small expression language built for Resterm. It targets the request format, workflows and directives directly, which keeps scripts short and predictable. JavaScript hooks remain available when you need more.

Quick example (RTS module + request):

// rts/helpers.rts
module helpers
export fn authHeader(token) {
  return token ? "Bearer " + token : ""
}

# @use ./rts/helpers.rts
# @when env.has("feature")
# @assert response.statusCode == 200
GET https://api.example.com/users/{{= vars.get("user") }}
Authorization: {{= helpers.authHeader(vars.get("auth.token")) }}

Full reference: docs/restermscript.md.

Deep dive

OAuth 2.0

Client credentials, password grant and authorization code with PKCE. For auth code flows Resterm opens your browser, runs a local callback server on 127.0.0.1, captures the redirect and exchanges the code. Tokens are cached per environment and refreshed when they expire. Docs: docs/resterm.md#oauth-20-directive and _examples/oauth2.http.

Workflows and scripting

Chain requests with @workflow and @step, pass data between steps and add JS hooks where needed. Docs and sample: docs/resterm.md#workflows and _examples/workflows.http.

Compare runs

Run the same request across environments with @compare or --compare, then diff the responses side by side with g+c. Docs: docs/resterm.md#compare-runs.

Tracing and timeline

Add @trace with budgets to capture DNS, connect, TLS, TTFB and transfer timings. Resterm highlights overruns and can export spans to OpenTelemetry. Docs: docs/resterm.md#timeline--tracing.

Streaming (WebSocket and SSE)

Use @websocket with @ws steps or @sse to script and record streams. The Stream tab keeps transcripts and includes an interactive console. Docs: docs/resterm.md#streaming-sse--websocket.

gRPC

Unary and streaming calls with transcripts, metadata and body expansion. Docs: docs/resterm.md#grpc.

OpenAPI import

Convert OpenAPI 3 specs into .http collections with --from-openapi, from a local file or an http(s) URL. Choose the generated blocks with --openapi-mode requests, mocks or both. Remote fetches respect the global --insecure and --proxy flags. Docs: docs/cli.md#import-examples.

SSH tunnels

Route HTTP, gRPC, WebSocket and SSE traffic through bastions with @ssh profiles. Docs: docs/resterm.md#ssh-tunnels and _examples/ssh.http.

Kubernetes port-forwards

Same idea with @k8s profiles, targeting pods, services, deployments or statefulsets. Docs: docs/resterm.md#kubernetes-port-forwards and _examples/k8s.http.

Theming and bindings

Customize colors and keybindings with themes/*.toml and bindings.toml or bindings.json in the config directory. Docs: docs/resterm.md#theming and docs/resterm.md#custom-bindings.

Documentation

• docs/resterm.md covers request syntax, directives, scripting and transports.
• docs/cli.md covers resterm run, importers, collections and history.