This is a very simple wrapper around MathJax-Node, to which you can post snippets of LaTeX and get back and svg element that you can render as html. To start the server:

npm install
node index.js

The server will listen on port 6174 for requests. If you navigate to http://localhost:6174/ in your browser you should get the formula for the Gamma function:

To "htmlify" arbitrary latex, you need to post json-fied LaTex to the server. E.g. the following request will render an svg element displaying Green's Theorem:

POST http://localhost:6174/ HTTP/1.1
Content-Type: application/json

{
    "math": "\\int_C P\\,du + Q\\, dv = \\int\\!\\!\\!\\int_A \\left({\\partial Q\\over \\partial u} - {\\partial P\\over \\partial v}\\right) {1\\over \\sqrt{EG-F^2}}\\,dA"
}

The server has the AMScd package installed, so you can draw basic commutative diagrams:

POST http://localhost:6174/ HTTP/1.1
Content-Type: application/json

{
	"math": "\\begin{CD}\r\nA @>f>> B  \\\\\r\n@VVFV @VVFV\\\\\r\nF(A) @>F(f)>> F(B)\r\n\\end{CD}"
}

yields

Running within a Docker container

You can run this application as a docker container:

docker run -p 1729:6174 lawrencetaylor/mathjaxserver

This will expose the web application on port 1729 of your local machine.