diff --git a/collects/compiler/demodularizer/batch.rkt b/collects/compiler/demodularizer/batch.rkt
index bd98894ad3..6ec08d76ec 100644
--- a/collects/compiler/demodularizer/batch.rkt
+++ b/collects/compiler/demodularizer/batch.rkt
@@ -39,80 +39,13 @@ Here's the idea:
 - Then, it will pay to do dead code elimination and inlining, etc.
 |#
 
-(require racket/pretty
-         racket/system
-         racket/cmdline
-         "mpi.rkt"
-         "util.rkt"
-         "nodep.rkt"
-         "merge.rkt"
-         "gc-toplevels.rkt"
-         "alpha.rkt"
-         "module.rkt"
-         "replace-modidx.rkt"
-         compiler/decompile
-         compiler/zo-marshal
+(require racket/cmdline
          racket/set
-         raco/command-name)
-
-(define (main file-to-batch output-file)
-  (define-values (base name dir?) (split-path file-to-batch))
-  (when (or (eq? base #f) dir?)
-    (error 'batch "Cannot run on directory"))
-  
-  ;; Compile 
-  
-  (log-info "Compiling module")
-  (void (system* (find-executable-path "raco") "make" file-to-batch)) 
-  
-  (define merged-zo-path 
-    (or output-file
-        (path-add-suffix file-to-batch #"_merged.zo")))
-  
-  ;; Transformations
-  (define path-cache (make-hash))
-  
-  (log-info "Removing dependencies")
-  (define-values (batch-nodep top-lang-info top-self-modidx get-modvar-rewrite)
-    (parameterize ([MODULE-PATHS path-cache])
-      (nodep-file file-to-batch)))
-  
-  (log-info "Merging modules")
-  (define batch-merge
-    (parameterize ([MODULE-PATHS path-cache])
-      (merge-compilation-top get-modvar-rewrite batch-nodep)))
-  
-  ; Not doing this for now
-  ;(log-info "GC-ing top-levels")
-  (define batch-gcd
-    batch-merge
-    #;(gc-toplevels batch-merge))
-  
-  (log-info "Alpha-varying top-levels")
-  (define batch-alpha
-    (alpha-vary-ctop batch-gcd))
-  
-  (log-info "Replacing self-modidx")
-  (define batch-replace-modidx
-    (replace-modidx batch-alpha top-self-modidx))
-  
-  (define batch-modname
-    (string->symbol (regexp-replace #rx"\\.zo$" (path->string merged-zo-path) "")))
-  (log-info (format "Modularizing into ~a" batch-modname))
-  (define batch-mod
-    (wrap-in-kernel-module batch-modname batch-modname top-lang-info top-self-modidx batch-replace-modidx))
-  
-  (log-info "Writing merged zo")
-  (void
-   (with-output-to-file 
-       merged-zo-path
-     (lambda ()
-       (zo-marshal-to batch-mod (current-output-port)))
-     #:exists 'replace)))
+         raco/command-name
+         "main.rkt")
 
 
-(let ()
-  (define output-file (make-parameter #f))
+(let ([output-file (make-parameter #f)])
   (command-line #:program (short-program+command-name)
                 #:multi
                 [("-e" "--exclude-modules") path "Exclude <path> from flattening"
@@ -120,5 +53,7 @@ Here's the idea:
                 #:once-each
                 [("-o") dest-filename "Write output as <dest-filename>"
                  (output-file (string->path dest-filename))]
+                [("-g" "--garbage-collect") "Garbage-collect final module (unsound)"
+                 (garbage-collect-toplevels-enabled #t)]                         
                 #:args (filename) 
-                (main filename (output-file))))
+                (demodularize filename (output-file))))
diff --git a/collects/compiler/demodularizer/main.rkt b/collects/compiler/demodularizer/main.rkt
new file mode 100644
index 0000000000..36e8a140fb
--- /dev/null
+++ b/collects/compiler/demodularizer/main.rkt
@@ -0,0 +1,77 @@
+#lang racket/base
+(require compiler/cm
+         compiler/zo-marshal
+         "alpha.rkt"
+         "gc-toplevels.rkt"
+         "merge.rkt"
+         "module.rkt"
+         "mpi.rkt"
+         "nodep.rkt"
+         "replace-modidx.rkt")
+
+(provide current-excluded-modules
+         garbage-collect-toplevels-enabled
+         demodularize)
+
+(define garbage-collect-toplevels-enabled (make-parameter #f))
+
+(define logger (make-logger 'demodularizer (current-logger)))
+
+(define (demodularize file-to-batch [output-file #f])
+  (parameterize ([current-logger logger])
+    (define-values (base name must-be-dir?) (split-path file-to-batch))
+    (when must-be-dir?
+      (error 'demodularize "Cannot run on directory: ~a" file-to-batch))
+    (unless (file-exists? file-to-batch)
+      (error 'demodularize "File does not exist: ~a" file-to-batch))
+    
+    ;; Compile
+    (log-info "Compiling module")
+    (parameterize ([current-namespace (make-base-empty-namespace)])
+      (managed-compile-zo file-to-batch))
+    
+    (define merged-zo-path 
+      (or output-file
+          (path-add-suffix file-to-batch #"_merged.zo")))
+    
+    ;; Transformations
+    (define path-cache (make-hash))
+    
+    (log-info "Removing dependencies")
+    (define-values (batch-nodep top-lang-info top-self-modidx get-modvar-rewrite)
+      (parameterize ([MODULE-PATHS path-cache])
+        (nodep-file file-to-batch)))
+    
+    (log-info "Merging modules")
+    (define batch-merge
+      (parameterize ([MODULE-PATHS path-cache])
+        (merge-compilation-top get-modvar-rewrite batch-nodep)))
+    
+    (define batch-gcd
+      (if (garbage-collect-toplevels-enabled)
+          (begin
+            (log-info "GC-ing top-levels")
+            (gc-toplevels batch-merge))
+          batch-merge))
+    
+    (log-info "Alpha-varying top-levels")
+    (define batch-alpha
+      (alpha-vary-ctop batch-gcd))
+    
+    (log-info "Replacing self-modidx")
+    (define batch-replace-modidx
+      (replace-modidx batch-alpha top-self-modidx))
+    
+    (define batch-modname
+      (string->symbol (regexp-replace #rx"\\.zo$" (path->string merged-zo-path) "")))
+    (log-info (format "Modularizing into ~a" batch-modname))
+    (define batch-mod
+      (wrap-in-kernel-module batch-modname batch-modname top-lang-info top-self-modidx batch-replace-modidx))
+    
+    (log-info "Writing merged zo")
+    (void
+     (with-output-to-file 
+         merged-zo-path
+       (lambda ()
+         (zo-marshal-to batch-mod (current-output-port)))
+       #:exists 'replace))))
\ No newline at end of file