He provided build fixes, in particular to tame the SunOS toolchain,
and has fixed many (stream-related and other) bugs besides.
+Juho Snellman:
+ He provided several performance enhancements, including a better hash
+ function on strings, and removal of unneccessary bounds checks.
+
Brian Spilsbury:
He wrote Unicode-capable versions of SBCL's character, string, and
stream types and operations on them.