The Jargon File (version 4.4.7, 29 Dec 2003):
codewalker
 n.
    A program component that traverses other programs for a living. Compilers
    have codewalkers in their front ends; so do cross-reference generators and
    some database front ends. Other utility programs that try to do too much
    with source code may turn into codewalkers. As in ?This new vgrind feature
    would require a codewalker to implement.?
The Free On-line Dictionary of Computing (30 December 2018):
codewalker
    A program component that analyses other
   programs.  Compilers have codewalkers in their front ends;
   so do cross-reference generators and some database front
   ends.  Other utility programs that try to do too much with
   source code may turn into codewalkers.  As in "This new
   'vgrind' feature would require a codewalker to implement."
   [Jargon File]
   (1994-12-23)