diff --git a/Makefile b/Makefile
index 7d1b32e3d9..6757f2a985 100644
--- a/Makefile
+++ b/Makefile
@@ -159,7 +159,8 @@ racket/src/build/Makefile: racket/src/configure racket/src/Makefile.in
 # Catalog for sources and native packages; use "local" to bootstrap
 # from package directories (in the same directory as this makefile)
 # plus the GitHub repository of raw native libraries. Otherwise, it's
-# a URL (spaces allowed).
+# a catalog URL (spaces allowed), and the catalog is copied to ensure
+# consistency across queries:
 SRC_CATALOG = local
 
 # A URL embedded in documentation for remote searches, where a Racket
@@ -284,7 +285,7 @@ WIN32_RACO = racket\racket $(USER_CONFIG) -N raco -l- raco
 X_AUTO_OPTIONS = --skip-installed --deps search-auto --pkgs $(JOB_OPTIONS)
 USER_AUTO_OPTIONS = --scope user $(X_AUTO_OPTIONS)
 LOCAL_USER_AUTO = --catalog build/local/catalog $(USER_AUTO_OPTIONS)
-SOURCE_USER_AUTO_q = --catalog "$(SRC_CATALOG)" $(USER_AUTO_OPTIONS)
+SOURCE_USER_AUTO_q = --catalog build/catalog-copy $(USER_AUTO_OPTIONS)
 REMOTE_USER_AUTO = --catalog $(SVR_CAT) $(USER_AUTO_OPTIONS)
 REMOTE_INST_AUTO = --catalog $(SVR_CAT) --scope installation $(X_AUTO_OPTIONS)
 CONFIG_MODE_q = "$(CONFIG)" "$(CONFIG_MODE)"
@@ -389,7 +390,12 @@ fresh-user:
 	rm -rf build/user
 
 set-server-config:
-	$(RACKET) -l distro-build/set-server-config build/user/config/config.rktd $(CONFIG_MODE_q) "$(DOC_SEARCH)" "" "" ""
+	$(RACKET) -l distro-build/set-server-config build/user/config/config.rktd $(CONFIG_MODE_q) "" "" "$(DOC_SEARCH)" ""
+
+server-cache-config:
+	$(RACO) pkg config -i --set download-cache-dir build/cache
+	$(RACO) pkg config -i --set download-cache-max-files 1023
+	$(RACO) pkg config -i --set download-cache-max-bytes 671088640
 
 # Install packages from the source copies in this directory. The
 # packages are installed in user scope, but we set the add-on
@@ -408,9 +414,12 @@ packages-from-local:
 # `SRC_CATALOG':
 build-from-catalog:
 	$(MAKE) fresh-user
+	rm -rf build/catalog-copy
+	$(RACO) pkg catalog-copy "$(SRC_CATALOG)" build/catalog-copy
+	$(MAKE) server-cache-config
 	$(RACO) pkg install --all-platforms $(SOURCE_USER_AUTO_q) $(REQUIRED_PKGS) $(DISTRO_BUILD_PKGS)
 	$(MAKE) set-server-config
-	$(RACKET) -l- distro-build/pkg-info -o build/pkgs.rktd $(SRC_CATALOG)
+	$(RACKET) -l- distro-build/pkg-info -o build/pkgs.rktd build/catalog-copy
 	$(RACKET) -l distro-build/install-pkgs $(CONFIG_MODE_q) "$(PKGS)" $(SOURCE_USER_AUTO_q) --all-platforms
 	$(RACO) setup --avoid-main $(JOB_OPTIONS)
 
diff --git a/racket/collects/pkg/lib.rkt b/racket/collects/pkg/lib.rkt
index a8fec591d5..9312c7547d 100644
--- a/racket/collects/pkg/lib.rkt
+++ b/racket/collects/pkg/lib.rkt
@@ -2655,14 +2655,10 @@
         (update-pkg-cfg! 'installation-name val)]
        [(list (and key "download-cache-dir")
               val)
-        (unless (complete-path? val)
-          (pkg-error (~a "invalid value for config key\n"
-                         " not an absolute path\n"
-                         "  config key: ~a\n"
-                         "  given value: ~a")
-                     key
-                     val))
-        (update-pkg-cfg! (string->symbol key) val)]
+        (update-pkg-cfg! (string->symbol key) (if (complete-path? val)
+                                                  val
+                                                  (path->string
+                                                   (path->complete-path val))))]
        [(list (and key (or "download-cache-max-files"
                            "download-cache-max-bytes"))
               val)