My advice? Not share these DTOs among the applications in any kind of library. Or at least don't do this right now.

I know, seems very counter intuitive. You are duplicating code, right? But this is not a business rule, so you can be more flexible.

The service that sends the DTO needs to be rigid in his message contract, like an Rest API. The service can't change the DTO in a way that could break the other services that are already consuming the informations from the DTO.

When a new field is added do DTO, you only update the other services that consume this DTO if they need the new field. Otherwise, forget it. Using Json as content-type you have the flexibility to create and send new atributes without breaks the code of the services that don't map these new fields on his actual versions of DTO.

But if this situation are really bothering you, you can follow the Rule of Three:

There are two "Rules of Three" in reuse: (a) It is three times as difficult to build reusable components as single use components, and (b) a reusable component should be tried out in three different applications before it will be sufficiently general to accept into a reuse library.

So, try to wait a bit more before share this DTO among the services.

My advice? Do not share these DTOs among the applications in any kind of library. Or at least don't do this right now.

I know, seems very counter-intuitive. You are duplicating code, right? But this is not a business rule, so you can be more flexible.

The service that sends the DTO needs to be rigid in his message contract, like an Rest API. The service can't change the DTO in a way that could break the other services that are already consuming the information from the DTO.

When a new field is added do DTO, you only update the other services that consume this DTO if they need the new field. Otherwise, forget it. Using JSON as content-type you have the flexibility to create and send new attributes without breaks the code of the services that don't map these new fields on his actual versions of DTO.

But if this situation is really bothering you, you can follow the Rule of Three:

There are two "Rules of Three" in reuse: (a) It is three times as difficult to build reusable components as single use components, and (b) a reusable component should be tried out in three different applications before it will be sufficiently general to accept into a reuse library.

So, try to wait a bit more before sharing this DTO among the services.