deltachat-node - v1.141.2


node.js bindings for deltachat-core-rust

npm Node version JavaScript Style Guide

deltachat-node primarily aims to offer two things:

  • A high level JavaScript api with syntactic sugar
  • A low level c binding api around deltachat-core-rust

This code used to live at deltachat-node

Table of Contents

Click to expand


By default the installation will try to use the bundled prebuilds in the npm package. If this fails it falls back to compile ../deltachat-core-rust from this repository, using scripts/rebuild-core.js.

To install from npm use:

npm install deltachat-node


  • Nodejs >= v18.0.0
  • rustup (optional if you can't use the prebuilds)

On Windows, you may need to also install Perl to be able to compile deltachat-core.

Build from source

If you want to build from source, make sure that you have rustup installed. You can either use npm install deltachat-node --build-from-source to force building from source or clone this repository and follow this steps:

  1. git clone
  2. cd deltachat-core-rust
  3. npm i
  4. npm run build

Our package.json file is located in the root directory of this repository, not inside this folder. (We need this in order to include the rust source code in the npm package.)

Use a git branch in deltachat-desktop

You can directly install a core branch, but make sure:

  • that you have typescript in your project dependencies, as it is likely required
  • you know that there are no prebuilds and so core is built during installation which is why it takes so long
npm install

If you want prebuilds for a branch that has a core pr, you might find an npm tar.gz package for that branch at The github ci also posts a link to it in the checks for each pr.

Use build-from-source in deltachat-desktop

If you want to use the manually built node bindings in the desktop client (for example), you can follow these instructions:

First clone the deltachat-desktop repository, e.g. with git clone

Then you need to make sure that this directory is referenced correctly in deltachat-desktop's package.json. You need to change deltachat-desktop/package.json like this:

diff --git i/package.json w/package.json
index 45893894..5154512c 100644
--- i/package.json
+++ w/package.json
@@ -83,7 +83,7 @@
"application-config": "^1.0.1",
"classnames": "^2.3.1",
"debounce": "^1.2.0",
- "deltachat-node": "1.79.3",
+ "deltachat-node": "file:../deltachat-core-rust/",
"emoji-js-clean": "^4.0.0",
"emoji-mart": "^3.0.1",
"emoji-regex": "^9.2.2",

Then, in the deltachat-desktop repository, run:

  1. npm i
  2. npm run build
  3. And npm run start to start the newly built client.

Workaround to build for x86_64 on Apple's M1

deltachat doesn't support universal (fat) binaries (that contain builds for both cpu architectures) yet, until it does you can use the following workaround to get x86_64 builds:

$ fnm install 19 --arch x64
$ fnm use 19
$ node -p process.arch
# result should be x64
$ rustup target add x86_64-apple-darwin
$ git apply patches/m1_build_use_x86_64.patch
$ CARGO_BUILD_TARGET=x86_64-apple-darwin npm run build
$ npm run test

(when using fnm instead of nvm, you can select the architecture) If your node and electron are already build for arm64 you can also try building for arm:

$ fnm install 18 --arch arm64
$ fnm use 18
$ node -p process.arch
# result should be arm64
$ npm_config_arch=arm64 npm run build
$ npm run test


const { Context } = require('deltachat-node')

const opts = {
addr: '[email]',
mail_pw: '[password]',

const contact = '[email]'

async function main() {
const dc ='./')
dc.on('ALL', console.log.bind(null, 'core |'))

try {
await dc.configure(opts)
} catch (err) {
console.error('Failed to configure because of: ', err)

console.log('fully configured')

const contactId = dc.createContact('Test', contact)
const chatId = dc.createChatByContactId(contactId)
dc.sendMessage(chatId, 'Hi!')

console.log('sent message')

dc.once('DC_EVENT_SMTP_MESSAGE_SENT', async () => {
console.log('Message sent, shutting down...')
console.log('stopped io')


this example can also be found in the examples folder examples/send_message.js

Generating Docs

We are currently migrating to automatically generated documentation. You can find the old documentation at old_docs.

to generate the documentation, run:

npx typedoc

The resulting documentation can be found in the docs/ folder. An online version can be found under


Tests and Coverage

Running npm test ends with showing a code coverage report, which is produced by nyc.

test output

The coverage report from nyc in the console is rather limited. To get a more detailed coverage report you can run npm run coverage-html-report. This will produce a html report from the nyc data and display it in a browser on your local machine.

To run the integration tests you need to set the CHATMAIL_DOMAIN environment variables. E.g.:

$ export
$ npm run test


We have the following scripts for building, testing and coverage:

  • npm run coverage Creates a coverage report and passes it to coveralls. Only done by Travis.
  • npm run coverage-html-report Generates a html report from the coverage data and opens it in a browser on the local machine.
  • npm run generate-constants Generates constants.js and events.js based on the deltachat-core-rust/deltachat-ffi/deltachat.h header file.
  • npm install After dependencies are installed, runs node-gyp-build to see if the native code needs to be rebuilt.
  • npm run build Rebuilds all code.
  • npm run build:core Rebuilds code in deltachat-core-rust.
  • npm run build:bindings Rebuilds the bindings and links with deltachat-core-rust.
  • ǹpm run clean Removes all built code
  • npm run prebuildify Builds prebuilt binary to prebuilds/$PLATFORM-$ARCH. Copies deltachat.dll from deltachat-core-rust for windows.
  • npm run download-prebuilds Downloads all prebuilt binaries from github before npm publish.
  • npm test Runs standard and then the tests in test/index.js.
  • npm run test-integration Runs the integration tests.
  • npm run hallmark Runs hallmark on all markdown files.


The following steps are needed to make a release:

  1. Wait until pack-module github action is completed
  2. Run npm publish to publish it to npm. You probably need write rights to npm.


Licensed under GPL-3.0-or-later, see LICENSE file for details.

Copyright © 2018 DeltaChat contributors.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see