diff --git a/compiler.rkt b/compiler.rkt
index 778f752..49710b9 100644
--- a/compiler.rkt
+++ b/compiler.rkt
@@ -361,35 +361,46 @@
 ;; FIXME: assumes the module has already been linked.  We should error out
 ;; if the module hasn't been linked yet.
 (define (compile-module-invoke a-module-name)
-  (let* ([linked (make-label 'linked)]
-	 [already-loaded (make-label 'alreadyLoaded)]
-	 [on-return-multiple (make-label 'onReturnMultiple)]
-	 [on-return (make-LinkedLabel (make-label 'onReturn)
-				     on-return-multiple)])
-  (make-instruction-sequence
-   `(,(make-TestAndBranchStatement (make-TestTrue
-				   (make-IsModuleLinked a-module-name))
-				  linked)
-     ;; TODO: raise an exception here that says that the module hasn't been
-     ;; linked yet.
-     ,(make-DebugPrint (make-Const 
-		        (format "DEBUG: the module ~a hasn't been linked in!!!"
-				(ModuleName-name a-module-name))))
-     ,(make-GotoStatement (make-Label already-loaded))
-     ,linked
-     ,(make-TestAndBranchStatement (make-TestTrue 
-				    (make-IsModuleInvoked a-module-name))
-				   already-loaded)
-     ,(make-PushControlFrame/Call on-return)
-     ,(make-GotoStatement (ModuleEntry a-module-name))
-     ,on-return-multiple
-     ,(make-PopEnvironment (make-SubtractArg (make-Reg 'argcount)
-					     (make-Const 1))
-			   (make-Const 0))
-     ,on-return
-     ,already-loaded))))
+  (cond
+   [(kernel-module-name? a-module-name)
+    empty-instruction-sequence]
+   [else
+    (let* ([linked (make-label 'linked)]
+           [already-loaded (make-label 'alreadyLoaded)]
+           [on-return-multiple (make-label 'onReturnMultiple)]
+           [on-return (make-LinkedLabel (make-label 'onReturn)
+                                        on-return-multiple)])
+      (make-instruction-sequence
+       `(,(make-TestAndBranchStatement (make-TestTrue
+                                        (make-IsModuleLinked a-module-name))
+                                       linked)
+         ;; TODO: raise an exception here that says that the module hasn't been
+         ;; linked yet.
+         ,(make-DebugPrint (make-Const 
+                            (format "DEBUG: the module ~a hasn't been linked in!!!"
+                                    (ModuleName-name a-module-name))))
+         ,(make-GotoStatement (make-Label already-loaded))
+         ,linked
+         ,(make-TestAndBranchStatement (make-TestTrue 
+                                        (make-IsModuleInvoked a-module-name))
+                                       already-loaded)
+         ,(make-PushControlFrame/Call on-return)
+         ,(make-GotoStatement (ModuleEntry a-module-name))
+         ,on-return-multiple
+         ,(make-PopEnvironment (make-SubtractArg (make-Reg 'argcount)
+                                                 (make-Const 1))
+                               (make-Const 0))
+         ,on-return
+         ,already-loaded)))]))
 
 
+(: kernel-module-name? (ModuleName -> Boolean))
+;; Produces true if the module is hardcoded.
+(define (kernel-module-name? name)
+  (or (and (eq? (ModuleName-name name) '#%kernel)
+           (eq? (ModuleName-real-path name) '#%kernel))
+      (eq? (ModuleName-name name) 'whalesong/lang/kernel)))
+
 
 
 
diff --git a/js-assembler/assemble.rkt b/js-assembler/assemble.rkt
index edc3d3d..639779f 100644
--- a/js-assembler/assemble.rkt
+++ b/js-assembler/assemble.rkt
@@ -12,7 +12,8 @@
          racket/string
          racket/list)
 
-(provide assemble/write-invoke
+(provide assemble/write-invoke-module-as-main
+         assemble/write-invoke
          fracture
          assemble-basic-block
          assemble-statement)
@@ -23,6 +24,14 @@
 
 
 
+
+(: assemble/write-invoke-module-as-main (Symbol Output-Port -> Void))
+(define (assemble/write-invoke-module-as-main module-name op)
+  ;; FIXME
+  (void))
+
+
+
 (: assemble/write-invoke ((Listof Statement) Output-Port -> Void))
 ;; Writes out the JavaScript code that represents the anonymous invocation expression.
 ;; What's emitted is a function expression that, when invoked, runs the
diff --git a/js-assembler/mini-runtime.js b/js-assembler/mini-runtime.js
index cac6885..5c4e64c 100644
--- a/js-assembler/mini-runtime.js
+++ b/js-assembler/mini-runtime.js
@@ -1108,6 +1108,7 @@
     };
 
 
+    var HaltError = function() {}
 
 
     var trampoline = function(MACHINE, initialJump) {
@@ -1138,7 +1139,10 @@
 			    0);
 			return;
 		    }
-		} else {
+		} else if (e instanceof HaltError) {
+                    // FIXME: work out what it really means to Halt.
+                    return;
+                } else {
 		    MACHINE.running = false;
 	            return MACHINE.params.currentErrorHandler(MACHINE, e);
 		}
@@ -1248,6 +1252,6 @@
     exports['heir'] = heir;
     exports['makeClassPredicate'] = makeClassPredicate;
 
-
+    exports['HaltError'] = HaltError;
 
 }).call(this);
\ No newline at end of file
diff --git a/package.rkt b/js-assembler/package.rkt
similarity index 91%
rename from package.rkt
rename to js-assembler/package.rkt
index 992503c..3717657 100644
--- a/package.rkt
+++ b/js-assembler/package.rkt
@@ -1,17 +1,17 @@
 #lang racket/base
 
-(require "compiler.rkt"
-         "compiler-structs.rkt"
-	 "parse-bytecode.rkt"
-	 "language-namespace.rkt"
-         "il-structs.rkt"
-         "bootstrapped-primitives.rkt"
-         "get-module-bytecode.rkt"
-         "get-dependencies.rkt"
-         "js-assembler/assemble.rkt"
-         "js-assembler/get-runtime.rkt"
-         "lexical-structs.rkt"
-         "quote-cdata.rkt"
+(require "assemble.rkt"
+         "get-runtime.rkt"
+         "../compiler.rkt"
+         "../compiler-structs.rkt"
+	 "../parse-bytecode.rkt"
+	 "../language-namespace.rkt"
+         "../il-structs.rkt"
+         "../bootstrapped-primitives.rkt"
+         "../get-module-bytecode.rkt"
+         "../get-dependencies.rkt"
+         "../lexical-structs.rkt"
+         "../quote-cdata.rkt"
          racket/runtime-path
          racket/port
          racket/list
diff --git a/tests/test-assemble.rkt b/tests/test-assemble.rkt
index 736659e..92f2356 100644
--- a/tests/test-assemble.rkt
+++ b/tests/test-assemble.rkt
@@ -9,6 +9,8 @@
          racket/promise
          racket/runtime-path)
 
+(printf "test-assemble.rkt\n")
+
 (define runtime (get-runtime))
 
 
diff --git a/tests/test-browser-evaluate.rkt b/tests/test-browser-evaluate.rkt
index bfcdba9..2483bd4 100644
--- a/tests/test-browser-evaluate.rkt
+++ b/tests/test-browser-evaluate.rkt
@@ -1,8 +1,9 @@
 #lang racket
 (require "../js-assembler/get-runtime.rkt"
          "../browser-evaluate.rkt"
-         "../package.rkt")
-         
+         "../js-assembler/package.rkt")
+
+(printf "test-browser-evaluate.rkt\n")
 
 
 (define should-follow? (lambda (p) #t))
diff --git a/tests/test-compiler-2.rkt b/tests/test-compiler-2.rkt
index 9c4bc40..e0281f7 100644
--- a/tests/test-compiler-2.rkt
+++ b/tests/test-compiler-2.rkt
@@ -5,7 +5,7 @@
          "../simulator/simulator-helpers.rkt"
          "test-helpers.rkt")
 
-
+(printf "test-compiler-2.rkt\n")
 
 ;; run: machine -> (machine number)
 ;; Run the machine to completion.
diff --git a/tests/test-compiler.rkt b/tests/test-compiler.rkt
index 1e537b6..1bf1baf 100644
--- a/tests/test-compiler.rkt
+++ b/tests/test-compiler.rkt
@@ -5,7 +5,10 @@
          "../simulator/simulator-helpers.rkt"
          "../parameters.rkt"
          "test-helpers.rkt"
-         racket/runtime-path)
+         racket/runtime-path
+         rackunit)
+
+(printf "test-compiler.rkt\n")
 
 (define-runtime-path this-test-path ".")
 
@@ -1339,12 +1342,16 @@
       #:with-bootstrapping? #t)
 
 
-(parameterize ([current-module-path (build-path this-test-path "foo.rkt")])
-  (test '(module foo racket/base
-           (printf "hello world"))
-        (make-undefined)
+(parameterize ([current-module-path (build-path this-test-path "foo.rkt")]
+               [current-simulated-output-port (open-output-bytes)])
+  (test '(module foo '#%kernel
+           (display "hello world")
+           (newline))
+        (void)
         #:as-main-module 'whalesong/tests/foo.rkt
-        #:with-bootstrapping? #t))
+        #:with-bootstrapping? #t)
+  (check-equal? (get-output-bytes (current-simulated-output-port))
+                #"hello world\n"))
 
 
 
diff --git a/tests/test-conform-browser.rkt b/tests/test-conform-browser.rkt
index 3354fa2..4d58d0f 100644
--- a/tests/test-conform-browser.rkt
+++ b/tests/test-conform-browser.rkt
@@ -1,10 +1,12 @@
 #lang racket
 (require "../browser-evaluate.rkt"
-         "../package.rkt"
+         "../js-assembler/package.rkt"
 	 "../js-assembler/get-runtime.rkt"
          racket/port
          racket/runtime-path)
 
+(printf "test-conform-browser.rkt\n")
+
 (define-runtime-path conform-path (build-path "conform"))
 
 
diff --git a/tests/test-earley-browser.rkt b/tests/test-earley-browser.rkt
index 49458be..741678a 100644
--- a/tests/test-earley-browser.rkt
+++ b/tests/test-earley-browser.rkt
@@ -1,12 +1,14 @@
 #lang racket
 (require "../browser-evaluate.rkt"
-         "../package.rkt"
+         "../js-assembler/package.rkt"
 	 "../js-assembler/get-runtime.rkt"
          racket/port
          racket/runtime-path
          racket/runtime-path
          (for-syntax racket/base))
 
+(printf "test-earley-browser.rkt\n")
+
 (define-runtime-path earley-file-path (build-path "earley"))
 
 
diff --git a/tests/test-get-dependencies.rkt b/tests/test-get-dependencies.rkt
index 3b86133..2a735ba 100644
--- a/tests/test-get-dependencies.rkt
+++ b/tests/test-get-dependencies.rkt
@@ -7,6 +7,8 @@
          racket/runtime-path
          rackunit)
 
+(printf "test-get-dependencies.rkt\n")
+
 (define-runtime-path compiler-path "..")
 
 
diff --git a/tests/test-package.rkt b/tests/test-package.rkt
index fa18574..8dda8d3 100644
--- a/tests/test-package.rkt
+++ b/tests/test-package.rkt
@@ -1,7 +1,8 @@
 #lang racket/base
 
-(require "../package.rkt")
+(require "../js-assembler/package.rkt")
 
+(printf "test-package.rkt\n")
 
 
 (define (follow? p)
diff --git a/tests/test-parse-bytecode.rkt b/tests/test-parse-bytecode.rkt
index 043deff..ed0351a 100644
--- a/tests/test-parse-bytecode.rkt
+++ b/tests/test-parse-bytecode.rkt
@@ -11,6 +11,8 @@
          racket/runtime-path
          (for-syntax racket/base))
 
+(printf "test-parse-bytecode.rkt\n")
+
 (define-runtime-path this-test-path ".")
 
 (define (run-zo-parse stx)
diff --git a/tests/test-parse.rkt b/tests/test-parse.rkt
index 8bb4e37..e5ae9ef 100644
--- a/tests/test-parse.rkt
+++ b/tests/test-parse.rkt
@@ -6,6 +6,8 @@
          "../lam-entry-gensym.rkt"
          (for-syntax racket/base))
 
+(printf "test-parse.rkt\n");
+
 ; Test out the compiler, using the simulator.
 (define-syntax (test stx)
   (syntax-case stx ()
diff --git a/tests/test-simulator.rkt b/tests/test-simulator.rkt
index 50e504b..a770cdc 100644
--- a/tests/test-simulator.rkt
+++ b/tests/test-simulator.rkt
@@ -6,6 +6,8 @@
          "../simulator/simulator-primitives.rkt"
          "../simulator/simulator.rkt")
 
+(printf "test-simulator.rkt\n")
+
 
 (define-syntax (test stx)
   (syntax-case stx ()