Lost in transition: the current state of the Julia ecosystem?

Similarly, Gumbo itself is at v0.3.0 on Julia v0.6, despite the fact that pkg.julialang.org lists

Julia v0.5: 0.3.0 (7 months ago) /  Tests pass. 
Julia v0.6: 0.4.0 (a month ago) /  Tests pass.

How can this be possible on a brand new Julia v0.6 install?

julia> versioninfo()
Julia Version 0.6.0
Commit 903644385b (2017-06-19 13:05 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin13.4.0)
  CPU: Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz
  WORD_SIZE: 64
  BLAS: libopenblas (USE64BITINT DYNAMIC_ARCH NO_AFFINITY Haswell)
  LAPACK: libopenblas64_
  LIBM: libopenlibm
  LLVM: libLLVM-3.9.1 (ORCJIT, skylake)