For vkDoom it's not a port to C3. What it demonstrates is instead C <=> C3 interop. I removed some of the central functions from the C code and implemented those in C3. The script compiles the C files into .o files with the normal C compiler, then uses the C3 compiler to compile the .c3 files into .o files. Finally all are linked together into a single binary showing off the simple ABI compatibility story (no extra annotations are needed to ensure compatibility - all C3 functions are automatically callable as C functions)

In regards to the versioning, I've gone through two versioning schemes for the pre-alpha. 0.1.0 is the first version I felt was sufficiently feature complete. Minor version changes (e.g. 0.1.x -> 0.2.x) is for any breaking changes. Minor version doesn't say how close it is to version 1.0 (minor version will continue after 0.9.x with 0.10.x). The 0.1 version was out in April. I try to make the compiler as solid as possible, but I would need thousands (rather than somewhere above 400) tests before I feel confident in the compiler.

Releasing 0.1 means I think that the language design is mostly there now, so fewer changes are coming. But joining any language before 1.0 is a bumpy ride.

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