diff --git a/pkgs/compatibility-pkgs/compatibility-lib/info.rkt b/pkgs/compatibility-pkgs/compatibility-lib/info.rkt
index 117849a..c6da929 100644
--- a/pkgs/compatibility-pkgs/compatibility-lib/info.rkt
+++ b/pkgs/compatibility-pkgs/compatibility-lib/info.rkt
@@ -1,3 +1,5 @@
 #lang info
 (define collection 'multi)
-(define deps '("base" "net-lib"))
+(define deps '("base" 
+               "net-lib"
+               "sandbox-lib"))
diff --git a/pkgs/lazy/mz-without-promises.rkt b/pkgs/compatibility-pkgs/compatibility-lib/lazy/mz-without-promises.rkt
similarity index 100%
rename from pkgs/lazy/mz-without-promises.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/lazy/mz-without-promises.rkt
diff --git a/racket/lib/collects/mzlib/private/sigmatch.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzlib/private/sigmatch.rkt
similarity index 100%
rename from racket/lib/collects/mzlib/private/sigmatch.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzlib/private/sigmatch.rkt
diff --git a/racket/lib/collects/mzlib/private/sigutil.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzlib/private/sigutil.rkt
similarity index 100%
rename from racket/lib/collects/mzlib/private/sigutil.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzlib/private/sigutil.rkt
diff --git a/racket/lib/collects/mzlib/private/unitidmap.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzlib/private/unitidmap.rkt
similarity index 100%
rename from racket/lib/collects/mzlib/private/unitidmap.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzlib/private/unitidmap.rkt
diff --git a/pkgs/sandbox-lib/mzlib/sandbox.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzlib/sandbox.rkt
similarity index 100%
rename from pkgs/sandbox-lib/mzlib/sandbox.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzlib/sandbox.rkt
diff --git a/racket/lib/collects/mzlib/unit200.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzlib/unit200.rkt
similarity index 100%
rename from racket/lib/collects/mzlib/unit200.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzlib/unit200.rkt
diff --git a/racket/lib/collects/mzlib/unitsig200.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzlib/unitsig200.rkt
similarity index 100%
rename from racket/lib/collects/mzlib/unitsig200.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzlib/unitsig200.rkt
diff --git a/racket/lib/collects/mzscheme/lang/reader.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/lang/reader.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/lang/reader.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/lang/reader.rkt
diff --git a/racket/lib/collects/mzscheme/main.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/main.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/main.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/main.rkt
diff --git a/racket/lib/collects/mzscheme/private/old-ds.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-ds.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/private/old-ds.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-ds.rkt
diff --git a/racket/lib/collects/mzscheme/private/old-if.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-if.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/private/old-if.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-if.rkt
diff --git a/racket/lib/collects/mzscheme/private/old-procs.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-procs.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/private/old-procs.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-procs.rkt
diff --git a/racket/lib/collects/mzscheme/private/old-rp.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-rp.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/private/old-rp.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/old-rp.rkt
diff --git a/racket/lib/collects/mzscheme/private/stxmz-body.rkt b/pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/stxmz-body.rkt
similarity index 100%
rename from racket/lib/collects/mzscheme/private/stxmz-body.rkt
rename to pkgs/compatibility-pkgs/compatibility-lib/mzscheme/private/stxmz-body.rkt