autogolf with zlib

#!/usr/bin/env tclsh
#

package require zlib

set algos {
    "compress 9" 	decompress
    "deflate 9" 	inflate
    "gzip -level 9" 	gunzip
}

set output [read stdin]

set sizes [dict map {c _} $algos {
    string length [zlib {*}[linsert $c 1 $output]]
}]

set sizes [lsort -stride 2 -index 1 -integer $sizes]

set c [lindex $sizes 0]
set d [dict get $algos $c]

set b64cstr [binary encode base64 [zlib {*}[linsert $c 1 $output]]]

set pgm "package require zlib\n"
append pgm "puts \[zlib $d \[binary decode base64 [list $b64cstr]\]\]"
puts "# [string length $pgm] bytes (excluding final newline):"
puts $pgm

# output for the old lady:
# # 384 bytes (excluding final newline):
# package require zlib
# puts [zlib inflate [binary decode base64 5ZCxTsQwEET7fMV016B8B3RIRKLey/psg/Ge7Jys/D3ei0+5oBRUCERn7T7PzszgTDIolEEREhiBeEZxglwoBCmGQTiFuQe6J7DEw4T3KKUyM7Izd9zkaFL0oaLPJjk6ZyUOIYC96btu+NaxfPZskooMKliStzboJjLunm/t7WOuPKq0Wnz54sg0OUyCkabRXWfN5M/kOfrEKvFYj9AxXxKrmUa0/b513WyNr938wqD17PXYB1kfzaK6SVqB/aDjQq6+b539+U5YrCq8qhrBid02Utf7jfBCrq5buf+pOycpm5u3+pEhJ4xyqdO++wQ=]]