Divi 4/5 Extension compatibility

Hey Andrew,

The Divi 4.x API isn't deprecated yet - it's the API used in the current version of Divi. The Divi 5.0 API isn't available yet, and it while the Divi 5 public alpha phase seems to be getting close, it will likely be many months, possibly a year or more, before Divi 5 officially releases, replacing Divi 4. Once Divi 5 is released, Divi 4 modules should continue to work, albeit via a slower method than new Divi 5 modules.

So I'd consider your time frame - if the client needs to be able to use it on a live site in the near future, then you'd probably need to create it using the Divi 4 API - Divi 5 isn't going to be considered production-ready for some time. Otherwise, if it's a less immediate requirement and / or the client is able to run an early alpha / beta release of Divi 5 (which may be missing features / have compatibility issues with various plugins, etc) then you may be able to get away with jumping straight to Divi 5.

If your client will go for it, you may wish to build it as a Divi 4 extension that can safely be used now, and then as a separate piece of work add Divi 5 compatibility, as per the following tutorials:

https://devalpha.elegantthemes.com/docs/category/converting-divi-4-module-to-divi-5/

The main difference between a Divi 4 extension and a Divi 5 extension is that the module settings which were defined using PHP in Divi 4 are now defined using React in Divi 5. While it will probably be possible for you to reuse some of the Divi 4 code in the Divi 5 extension there will also be some fairly significant reworking required (e.g. in terms of how the code is called). It will take a while, though hard to say how long - that will depend on the nature of the extension, your proficiency with React, etc. Point being, converting between the two will be a major piece of work (and learning) and you should make sure your client is willing to pay for it. I'd probably give yourself a week at an absolute minimum, but be prepared for it to take longer.