1.2.1 • Public • Published


DEPRECATED: I HAVE STARTED A NEW PROJECT NAMED SendScript. It is a much simpler package with a more expressive dsl for client usage.

Furver is a minimal RPC solution that uses JSON and Node.js. Turn any JavaScript module into a simple to use client API that is easy to learn while also expressive enough for advanced use-cases.

NPM NPM Downloads Standard Code Style License

Table of Contents


  • Low code.
  • Makes it easy to quickly iterate.
  • Supports bulk requests with an intuitive client js API.
  • Parallel operations out of the box.
  • Covers both simple and complicated use-cases.

Getting Started

Covers the basic use case of defining a module, starting a server and performing requests with and without the client.


npm install furver -g

Define a module

// ./example/getting-started.mjs

const items = []

export default {
  push (x) {
    return items.push(x)
  items () {
    return items
  ping () {
    return 'pong'

Start the server

Port 5000 for the following examples.

furver server ./example/getting-started.mjs --port 5000

Now for the http clients.

Request using curl

curl http://localhost:5000 -d '["ping"]'

Let's add some numbers to our items array.

curl http://localhost:5000 -d '["array", ["push", 1], ["push", 2], ["push", 3], ["items"]]'

Also support requests with GET method:

curl -G "http://localhost:$PORT" --data-urlencode body='["inc", 42]'

We use the -G and --data-urlencode to perform a GET request with properly encoded JSON in the body query param.

Request using the furver client

Now let's use the furver client module and api.push some letters.

import client from './client.mjs'

const api = await client({
  endpoint: 'http://localhost:5000'

console.log(await Promise.all([

  api.call(['push', 'b']),
  api.call([['ref', 'push'], 'c']),
  api.call([api.push, 'd'])


console.log(await api.items())
[ 4, 5, 6, 7 ]
  1,   2,   3,   'a',
  'b', 'c', 'd'

These are all equivalent ways of calling the push function in the server module. Read more about the client and lisp if you want to learn more.


You can start a server by pointing to a module. This can be a npm package or another file on the filesystem.

npm install ramda # A utility library.
npx furver server --port 3000 ramda ./example/api.mjs

Defining multiple modules will result in the modules being merged into a single API. The function of the most right module will take precedence when the modules have conflicting function names.

You can now perform requests using a furver client.

Read more about the Furver server.


Now that we have a server running we can use the client to perform requests using either the client functions or a simple JSON Lisp.

Here an working example of the JavaScript client.

Use in your code

(async function() {
  const { default: FurverClient } = await import('./client.mjs')

  // Fetches the schema and installs the schema methods on the api.
  const api = await FurverClient({endpoint: `http://localhost:${process.env.PORT}`})

  // These function calls result in a single request that is run in parallel on
  // the server.
  console.log(await Promise.all([
    api.identity('hello world'),

  // We can write the same query using the JSON Lisp
  console.log(await api.call(['array', ['identity', 'hello world'], ['timestamp'], ['version']]))

  // Those are many quotes, we can reduce it by using the function reference.
  const { identity, timestamp, version, array } = api
  console.log(await api.call([array, [identity, 'hello world'], [timestamp], [version]]))
[ 'hello world', 1694650272974, '1.2.1' ]
[ 'hello world', 1694650272979, '1.2.1' ]
[ 'hello world', 1694650272982, '1.2.1' ]

All three ways are equivalent and valid ways of writing a furver Lisp program that is run server-side.

This client is compatible with the browser and Node.js.

Client REPL

You can also start talking with a Furver server using the cli.

furver repl --url http://localhost:3000

This will start a prompt that takes valid JavaScript or a Lisp expression.

> identity('hello')
> ['identity', 'world']
> [identity, 'goodbye']


By default the server hosts a browser friendly bundled version of the client at /client.min.js. This script registers the furver global variable.

You can try this client in the playground by starting a furver server and opening http://localhost:3000/playground in your browser.

Read more about the client.


Furver's Lisp-like language allows developers to perform complex aggregations and operations in a single request. It builds ontop of JSON by using arrays for its s-expressions.

Read more about the furver lisp.


The goal of Furver's cli is to provide you with all the tools to use, test and debug Furver servers.

furver --help
furver <command>

  furver server <modules..>  start server
  furver repl [modules..]    start a local server or client repl
  furver client              start client repl. Use repl --url instead
  furver schema [modules..]  print schema of api

      --help     Show help                                             [boolean]
      --version  Show version number                                   [boolean]
      --url                                                             [string]
      --modules  Name or path to modules                                 [array]
  -v, --verbose                                                        [boolean]
  -p, --port                                          [number] [default: "8999"]

Read more about the Furver CLI.


See the CHANGELOG.md for a list of changes over time.


Want to contribute? The CONTRIBUTING.md might help you get started quicker.


See the LICENSE.txt file for details.

Package Sidebar


npm i furver

Weekly Downloads






Unpacked Size

103 kB

Total Files


Last publish


  • bas080