Due to ServiceLoader problems with:

• file I/O at scale as discussed in io.jsonwebtoken.CompressionCodec: Error reading configuration file #648 (comment) as well as
• ClassLoader problems in JEE environments as discussed in Multiple applications using jjwt leading to ServiceConfigurationError io.jsonwebtoken.jackson.io.JacksonSerializer not a subtype #751 (and perhaps this extends to OSGI environments),

we should migrate away from using the JDK ServiceLoader concept, and at a minimum revert to the previous logic in 0.10.x:

Another approach is to create our own API concept similar to ServiceLoader and allow JJWT users to specify their own implementation on the JwtBuilder or JwtParserBuilder. 95% of users would likely never configure a custom one, but it does provide an option to fix things quickly if the default implementation has problems (as opposed to waiting for a new JJWT release).