Nebulous Plasma Muffin


    0.4.0 • Public • Published


    Creates a proxy to your HTTP app with HTTPS, using provided certificate files. This is designed as a convenience.

    Setup Instructions

    You'll need to generate a self-signed certificiate, or one from a locally trusted CA.


    The mkcert package, available on Homebrew, is very easy to use.

    1. Ensure you have Homebrew installed.
    2. Run brew install mkcert nss. mkcert will create the certificate. nss will get Firefox to recognize it. (Other browsers will recognize it automatically.)
    3. Run mkcert -install to generate your local CA.
    4. Change to the directory where you'd like to save the certificates. I recommend a /certificates directory in your project.
    5. Run mkcert localhost.
    6. Ensure that the two generated files, localhost.pem and localhost-key.pem, are ignored in your source control. They would only be trusted on your local machine, so other users would run into errors.

    Other Operating Systems

    Contributions welcome!

    Alternative Hostnames

    It may be useful to use an alternative hostname for your project. For example, if you need to use cookies, you may wish to serve from To do so, you'll need to make sure the alternative hostname is in your /etc/hosts file (or equivalent). In step 5 above, replace localhost with your full domain, i.e. mkcert


    In parallel with your development environment, run this as follows:

    npx https-cert-proxy --cert path/to/localhost.pem --key path/to/localhost-key.pem

    By default, this will proxy your existing http://localhost:3000 to https://localhost:8030. These ports can be configured using flags. For example, this will proxy from 80 (the default HTTP port) to 443 (the default HTTPS port):

    npx https-cert-proxy --cert path/to/localhost.pem --key path/to/localhost-key.pem --source 80 --destination 443

    I find it easiest to have these scripts in my package.json, using the package concurrently:

      "scripts": {
        "dev": "concurrently -n w: npm:dev-*",
        "dev-web": "YOUR CURRENT DEV SCRIPT",
        "dev-ssl": "https-cert-proxy --cert path/to/localhost.pem --key path/to/localhost-key.pem"
      "devDependencies": {
        "concurrently": "^5.1.0",
        "https-cert-proxy": "^0.0.1"

    Configuring with environment variables

    If you often run with the same settings, you can set up environment variables in addition to using the command-line options. The variables are as follows:

    Variable Setting
    HCP_SOURCE Source port
    HCP_DESTINATION Destination port
    HCP_CERTFILE The certificate file
    HCP_KEYFILE The key file

    If you set the HCP_CERTFILE and HCP_KEYFILE variables, you do not need to use the --cert and --key command-line options.


    Copyright (c) 2020-21 Todd Dukart. Licensed under the BSD-3-Clause.




    npm i https-cert-proxy

    DownloadsWeekly Downloads






    Unpacked Size

    16.9 kB

    Total Files


    Last publish


    • tdukart