Unqualified electronic signature, how to implement for a company?

Question

Information Security

Good day toasters and toasters!
I read here and here information about the EDS .
I watched a video from the tax office here .
In the upcoming large project, the task is: the creation of an EDS for document circulation both within the company and between companies (on the territory of the Russian Federation).
Interested in Unqualified EP . How to make it? More precisely, what services offer it? Ideally, I would like some code or API with which I would interact in my program for signing contracts / invoices and so on ...
Is it possible to use an Unqualified ESfrom the tax to signing a document within the company and when signing an agreement between companies?
I would like to thank everyone who answered!

Answer 1

To solve such problems, you can use PKI based on your own corporate certification authority.
There are a lot of software solutions for implementing your own CA (both paid and free - open source) now.

Answer 2

1. Already happened - PGP
2. Already happened - no