There has been many requests to allow adding custom gateways. Many people maintain there own internal Middleware/Gateway servers. So, hopefully VitalPBX picks up on this and allows adding custom gateways.
While it’s cool and all you have your own “gateway”, is it really an SMS gateway which directly connects to the mobile carrier SMS networks or are you also sending and receiving through aggregators/carriers/wholesalers such as Twilio, Telnyx, Vonage, etc? Also, at least now in North America, you will need to go through The Campaign Registry (https://campaignregistry.com) for each of your numbers. Your carrier can also handle this for you.
So I suspect you’re using Twilio, Telnyx, Vonage, etc. Given that, you can alter their webhooks to point back to your API and you can do all the magic you need to do at that point. ie: Log and Relay
Not every one use Twilio, Telynks, etc, they are of course big players in the market and we respect their work but we are connected directly to mobile operators, of course not in every country but, our clients.
Also, we are not in North Americ and dont cover that part, we mostly cover African countries, both for SMS and Voice (as well as for VitalPBX services).
So we would need to be able to add our own SMS service on VitalPBX