How to convert the https server to Node.js from the usual key/certificate scheme to using Pre-Shared Key(PSK)?

Question

Node.js

There is a client-server project where a specialized server is written in Node.js HTTPS, and clients run on relatively low-power embedded systems. https protocol with key/certificate sets for clients and server (two-way TLS, the server requests a client certificate). So far, everything is fine, the project is working.
Now we need to add a new type of client to the system, implemented on a low-power embedded system with very limited cryptographic capabilities. A minimum set of symmetric cryptographic algorithms will be implemented. I have nothing to do with the development of the client, but the server is mine.
How to modify/reconfigure HTTPS from NODE.js so that the server supports PSK? Examples, descriptions, ideas?
A simple Google search gives a description of TLS-PSK and... a total lack of examples.

UPD . Finally the hands reached.
TLS-PSK is supported fine since 12.9
and it's already working, it took less than half a day to add TLS-PSK to the server and make a simple client to check.

Answer 1

TLS with PSK is practically not supported. Use Elliptic Curve Cryptography (ECDSA certificates and ECDHE key generation). It is much less demanding on the processor and is suitable even for smart cards. If your embedded system is not completely low-power, then it will be acceptable to work there.