diff --git a/command.rkt b/command.rkt
index 17bf23b..2f05889 100644
--- a/command.rkt
+++ b/command.rkt
@@ -131,7 +131,8 @@ version                print the version (~a)" (world:current-server-port) (worl
   (when (directory-exists? target-dir)
     (delete-directory/files target-dir))
   (copy-directory/files source-dir target-dir)
-  (for-each delete-it (find-files pollen-related-file? target-dir))
+  (parameterize ([world:current-project-root (current-directory)])
+    (for-each delete-it (find-files pollen-related-file? target-dir)))
   (displayln (format "completed to ~a" target-dir)))
 
 (define (handle-unknown command)
diff --git a/file.rkt b/file.rkt
index bd7147b..2110380 100644
--- a/file.rkt
+++ b/file.rkt
@@ -238,10 +238,11 @@
   (and (directory-exists? path) 
        (or (ends-with? (path->string path) "compiled"))))
 
-(define+provide (cache-file? path)
-  (or (ends-with? (path->string path) (world:current-cache-filename))))
 
+(define+provide (cache-file? path)
+  (ormap (λ(cache-name) (ends-with? (path->string path) cache-name)) world:cache-names))
 
+(require sugar/debug)
 (define+provide (pollen-related-file? file)
   (ormap (λ(proc) (proc file)) (list
                                 preproc-source? 
@@ -253,4 +254,5 @@
                                 null-source?
                                 racket-source?
                                 magic-directory?
-                                cache-file?)))
\ No newline at end of file
+                                cache-file?
+                                (world:current-unpublished-path?))))
\ No newline at end of file
diff --git a/scribblings/world.scrbl b/scribblings/world.scrbl
index fd1b26a..b800d35 100644
--- a/scribblings/world.scrbl
+++ b/scribblings/world.scrbl
@@ -129,4 +129,6 @@ Default separators used in decoding. The first two are initialized to @racket["\
 
 @defoverridable[compile-cache-active boolean?]{Whether the compile cache, which speeds up interactive sessions by saving compiled versions of Pollen source files, is active. Default is active (@racket[#t]).}
 
-@defoverridable[compile-cache-max-size exact-positive-integer?]{Maximum size of the compile cache. Default is 10 megabytes.}
\ No newline at end of file
+@defoverridable[compile-cache-max-size exact-positive-integer?]{Maximum size of the compile cache. Default is 10 megabytes.}
+
+@defoverridable[unpublished-path? (path? . -> . boolean?)]{Predicate that determines whether a path is omitted from @secref{raco_pollen_publish} operations. If the predicate is @racket[#t], then the path is omitted. The default, therefore, is @racket[#f].}
\ No newline at end of file
diff --git a/world.rkt b/world.rkt
index cae2d2d..216190f 100644
--- a/world.rkt
+++ b/world.rkt
@@ -86,4 +86,6 @@
 (define-settable extension-escape-char #\!)
 
 (define-settable compile-cache-active #t)
-(define-settable compile-cache-max-size (* 10 1024 1024)) ; = 10 megabytes
\ No newline at end of file
+(define-settable compile-cache-max-size (* 10 1024 1024)) ; = 10 megabytes
+
+(define-settable unpublished-path? (λ(path) #f))
\ No newline at end of file