I've just published draft #5 of SRFI 160.  It was submitted by John Cowan, author of the SRFI.

  https://srfi.schemers.org/srfi-160/

Here are John's comments on the draft:

  This version adds the xxxxxx@vector procedures, which write out @vectors in the lexical syntax format.  The implementation has progressed to SRFI 4, and the next effort will be to provide SRFI 4 analogues for u1 (bit) and c32 and c64 (complex) vector types.

Here's the diff:

  https://github.com/scheme-requests-for-implementation/srfi-160/compare/5b4e95bcc3e300e99879d58cf213620562849c84...756d53a4cb284e5e2e1c49c0b105e85fb0c77d0a

Regards,

SRFI Editor