Any Springfox alternatives out there?

Spring doc Open API is alternative going forward.

1. SpringDoc OpenAPI supports OAS 3.0
2. Supports more annotations like @MatrixParam which was not supported in springfox.
3. Spring boot 2.2.x works only with springdoc.

Refer the below link

https://techsparx.com/software-development/openapi/spring-boot-rest-api-docs.html

I haven't tried it myself yet, but this looks quite promising:

https://github.com/springdoc/springdoc-openapi

OpenAPI 3.0 is the successor of Open API 2.0 (sometimes referred to as Swagger, though that is actually the tooling around Open API). Not sure how much this project offers in terms of customization and how mature it is, but I guess it's worth a try ;-)

Update:
Since version 3, Spring Fox offers support for Open API 3. Please see the release log for more details.