Is there anything (in the plans) to make fidl cross platform?
Not sure what you mean. FIDL as a language and protocol is conceptually inherently cross platform. There are already bindings for multiple language platforms that can be generated from a FIDL specification, and theoretically one could implement a FIDL service anywhere. That said, FIDL services in the system provide a sort of ABI -- the F in FIDL stands for Fuchsia, after all -- and I'm not aware of any actual efforts to implement these on platforms that aren't Fuchsia.
Thanks! I was more going about the ecosystem - like grpc/protobuf have and support across languages/runtimes/systems.
We use FIDL on host (Linux & macos) platforms via the overnet project. As far as language ecosystems go, as swetland rightly points out below, being runtime agnostic is important to us. FIDL being easy to implement generators for new runtimes is part of that. There is some nascent documentation on porting runtimes here: https://fuchsia.dev/fuchsia-src/development/languages/new?hl...
This policy, like most technical decisions, may be amended when things change. We want people to have a consistent and stable platform to develop on, and if a language doesn't officially support our platform, it kind of doesn't make sense to support that language. And there's no commitment to support these languages for production services and end user development until there's a story for the stability of that toolchain on Fuchsia.
This shouldn't be surprising. Make a new system, bootstrap your programming environments. Why bother offering support for environments you've not yet bootstrapped?
As a thought experiment, consider the thousands of languages (including the tens or hundreds of popular ones) not listed on that page, and whether they're supported.
(Edit: I accidentally a word.)