diff --git a/contrib/aim/load.factor b/contrib/aim/load.factor
index 7262b9021c..50149bfe4a 100644
--- a/contrib/aim/load.factor
+++ b/contrib/aim/load.factor
@@ -1,7 +1,6 @@
 IN: scratchpad
 USING: kernel parser sequences words compiler ;
 
-{ 
-    "net-bytes"
-    "aim"
-} [ "/contrib/aim/" swap ".factor" append3 run-resource ] each
+REQUIRE: crypto ;
+
+PROVIDE: aim { "net-bytes.factor" "aim.factor" } ;
diff --git a/contrib/all.factor b/contrib/all.factor
new file mode 100644
index 0000000000..6c0d15155d
--- /dev/null
+++ b/contrib/all.factor
@@ -0,0 +1,10 @@
+USING: modules words  ;
+
+REQUIRE: aim cairo concurrency coroutines crypto dlists
+gap-buffer httpd math postgresql process random-tester
+splay-trees sqlite units ;
+
+"x11" vocab [
+    "factory" require
+    "x11" require
+]
diff --git a/contrib/cairo/load.factor b/contrib/cairo/load.factor
index 9c353e4284..384c9ab30f 100644
--- a/contrib/cairo/load.factor
+++ b/contrib/cairo/load.factor
@@ -3,6 +3,6 @@ USING: alien kernel parser compiler words sequences ;
 
 "cairo" "libcairo" add-simple-library
 
-"/contrib/cairo/cairo.factor" run-resource
+PROVIDE: cairo { "/contrib/cairo/cairo.factor" } ;
 
 { "cairo" } compile-vocabs
diff --git a/contrib/concurrency/load.factor b/contrib/concurrency/load.factor
index 4ef8059611..acbc482235 100644
--- a/contrib/concurrency/load.factor
+++ b/contrib/concurrency/load.factor
@@ -1,6 +1,7 @@
-IN: scratchpad
-USING: kernel parser compiler words sequences ;
+USING: modules ;
 
-"/contrib/concurrency/concurrency.factor" run-resource
-"/contrib/concurrency/concurrency-examples.factor" run-resource
-"/contrib/concurrency/concurrency-tests.factor" run-resource
+REQUIRE: dlists ;
+
+PROVIDE: concurrency
+{ "concurrency.factor" }
+{ "concurrency-examples.factor" "concurrency-tests.factor" } ;
diff --git a/contrib/coroutines.factor b/contrib/coroutines.factor
index 54256d4995..a790eab461 100644
--- a/contrib/coroutines.factor
+++ b/contrib/coroutines.factor
@@ -69,3 +69,5 @@ test2 f swap coresume . f swap coresume . f swap coresume . drop
 
 test3 f swap coresume . f swap coresume . f swap coresume . drop
 
+PROVIDE: coroutines ;
+
diff --git a/contrib/crypto/load.factor b/contrib/crypto/load.factor
index 86057af025..ba482802c0 100644
--- a/contrib/crypto/load.factor
+++ b/contrib/crypto/load.factor
@@ -1,26 +1,28 @@
 IN: scratchpad
 USING: kernel parser sequences words compiler ;
 
-{
-    "common"
-    "base64"
-    "barrett"
-    "montgomery"
-    "random"
-    "miller-rabin"
+REQUIRE: math ;
+
+PROVIDE: crypto {
+    "common.factor"
+    "base64.factor"
+    "barrett.factor"
+    "montgomery.factor"
+    "random.factor"
+    "miller-rabin.factor"
 
 ! Rngs
-    "blum-blum-shub"
+    "blum-blum-shub.factor"
 
 ! Hash
-    "crc32"
-    "md5"
-    "sha1"
+    "crc32.factor"
+    "md5.factor"
+    "sha1.factor"
 
 ! Block ciphers
-    "rc4"
+    "rc4.factor"
 
 ! Public key
-    "rsa"
+    "rsa.factor"
 
-} [ "/contrib/crypto/" swap ".factor" append3 run-resource ] each
+} ;
diff --git a/contrib/dlists.factor b/contrib/dlists.factor
index 7a125b16ee..951f354eec 100644
--- a/contrib/dlists.factor
+++ b/contrib/dlists.factor
@@ -1,6 +1,7 @@
 ! Copyright (C) 2005 Mackenzie Straight.
 ! See http://factor.sf.net/license.txt for BSD license.
-IN: dlists USING: generic kernel math ;
+IN: dlists
+USING: generic kernel math modules ;
 
 ! Double-linked lists.
 
@@ -60,3 +61,5 @@ C: dlist-node
 
 : dlist-length ( dlist -- length )
     0 swap [ drop 1 + ] dlist-each ;
+
+PROVIDE: dlists ;
diff --git a/contrib/factory/load.factor b/contrib/factory/load.factor
new file mode 100644
index 0000000000..f641964e6c
--- /dev/null
+++ b/contrib/factory/load.factor
@@ -0,0 +1,5 @@
+USING: modules ;
+
+REQUIRE: process concurrency x11 ;
+
+PROVIDE: factory { "factory.factor" } ;
diff --git a/contrib/gap-buffer/load.factor b/contrib/gap-buffer/load.factor
index 0fadd0ae90..d5bfbf3c69 100644
--- a/contrib/gap-buffer/load.factor
+++ b/contrib/gap-buffer/load.factor
@@ -1,13 +1,5 @@
 USING: kernel sequences parser words compiler ;
 
-[ "circular" "gap-buffer" ]
-
-! load
-dup [ "contrib/gap-buffer/" swap append ".factor" append run-file ] each
-
-! compile
-dup [ words [ try-compile ] each ] each
-
-! test
-[ "contrib/gap-buffer/" swap append "-tests.factor" append run-file ] each
-
+PROVIDE: gap-buffer
+{ "circular.factor" "gap-buffer.factor" }
+{ "circular-tests.factor" "gap-buffer-tests.factor" } ;
diff --git a/contrib/httpd/load.factor b/contrib/httpd/load.factor
index e8eef0cab1..f8f46729cc 100644
--- a/contrib/httpd/load.factor
+++ b/contrib/httpd/load.factor
@@ -1,30 +1,30 @@
 IN: scratchpad
 USING: words kernel parser sequences io compiler ;
 
-{ 
-    "mime"
-    "xml"
-    "http-common"
-    "html-tags"
-    "responder"
-    "httpd"
-    "cont-responder"
-    "callback-responder"
-    "prototype-js"
-    "html"
-    "embedded"
-    "file-responder"
-    "help-responder"
-    "inspect-responder"
-    "browser-responder"
-    "default-responders"
-    "http-client"
+PROVIDE: httpd { 
+    "mime.factor"
+    "xml.factor"
+    "http-common.factor"
+    "html-tags.factor"
+    "responder.factor"
+    "httpd.factor"
+    "cont-responder.factor"
+    "callback-responder.factor"
+    "prototype-js.factor"
+    "html.factor"
+    "embedded.factor"
+    "file-responder.factor"
+    "help-responder.factor"
+    "inspect-responder.factor"
+    "browser-responder.factor"
+    "default-responders.factor"
+    "http-client.factor"
 
-    "test/html"
-    "test/http-client"
-    "test/httpd"
-    "test/url-encoding"
-} [ "/contrib/httpd/" swap ".factor" append3 run-resource ] each
+    "test/html.factor"
+    "test/http-client.factor"
+    "test/httpd.factor"
+    "test/url-encoding.factor"
+} ;
 
 "To start the HTTP server, issue the following command in the listener:" print
 "  USE: httpd" print
diff --git a/contrib/load.factor b/contrib/load.factor
deleted file mode 100644
index e7689476b3..0000000000
--- a/contrib/load.factor
+++ /dev/null
@@ -1,21 +0,0 @@
-USING: kernel parser sequences ;
-{ 
-    "coroutines"
-    "dlists"
-    "process"
-    "splay-trees"
-} [ "/contrib/" swap ".factor" append3 run-resource ] each
-
-{
-  "cairo"
-  "concurrency"
-  "math"
-  "crypto"
-  "aim"
-  "gap-buffer"
-  "httpd"
-  "units"
-  "sqlite"
-  "postgresql"
-  "random-tester"
-} [ "/contrib/" swap "/load.factor" append3 run-resource ] each
diff --git a/contrib/math/load.factor b/contrib/math/load.factor
index f068373e47..760f9219a8 100644
--- a/contrib/math/load.factor
+++ b/contrib/math/load.factor
@@ -1,13 +1,13 @@
 IN: scratchpad
-USING: kernel parser sequences words compiler ;
+USING: modules ;
 
-{ 
-    "utils"
-    "combinatorics"
-    "analysis"
-    "polynomials"
-    "quaternions"
-    "matrices"
-    "statistics"
-    "numerical-integration"
-} [ "/contrib/math/" swap ".factor" append3 run-resource ] each
+PROVIDE: math { 
+    "utils.factor"
+    "combinatorics.factor"
+    "analysis.factor"
+    "polynomials.factor"
+    "quaternions.factor"
+    "matrices.factor"
+    "statistics.factor"
+    "numerical-integration.factor"
+} ;
diff --git a/contrib/postgresql/load.factor b/contrib/postgresql/load.factor
index 0dd9674626..0cd0acde1c 100644
--- a/contrib/postgresql/load.factor
+++ b/contrib/postgresql/load.factor
@@ -1,11 +1,7 @@
-IN: scratchpad
-USING: alien compiler kernel parser sequences words ;
+USING: alien modules ;
 
 "postgresql" "libpq" add-simple-library
 
-{
-    "libpq"
-    "postgresql"
-    "postgresql-test"
-    ! "private" ! Put your password in this file
-} [ "/contrib/postgresql/" swap ".factor" append3 run-resource ] each
+PROVIDE: postgresql
+{ "libpq" "postgresql" }
+{ "postgresql-test" } ;
diff --git a/contrib/process.factor b/contrib/process.factor
index b896a96d63..f27e10adea 100644
--- a/contrib/process.factor
+++ b/contrib/process.factor
@@ -9,3 +9,5 @@ FUNCTION: void* popen ( char* command, char* type ) ; compiled
     popen dup <c-stream> ;
 
 : !" parse-string system drop ; parsing
+
+PROVIDE: process ;
diff --git a/contrib/random-tester/load.factor b/contrib/random-tester/load.factor
index 06583c7cb6..349d6882c4 100644
--- a/contrib/random-tester/load.factor
+++ b/contrib/random-tester/load.factor
@@ -1,8 +1,5 @@
-USING: kernel parser sequences words compiler ;
-IN: scratchpad
-
-{
-    "utils"
-    "random"
-    "random-tester"
-} [ "/contrib/random-tester/" swap ".factor" append3 run-resource ] each
+PROVIDE: random-tester {
+    "utils.factor"
+    "random.factor"
+    "random-tester.factor"
+} ;
diff --git a/contrib/splay-trees.factor b/contrib/splay-trees.factor
index 7f8b7e20b8..245f55ac91 100644
--- a/contrib/splay-trees.factor
+++ b/contrib/splay-trees.factor
@@ -113,3 +113,5 @@ USING: namespaces words ;
 <splay-tree> "foo" set
 all-words [ dup word-name "foo" get set-splay ] each
 all-words [ dup word-name "foo" get get-splay drop ] each
+
+PROVIDE: splay-trees ;
diff --git a/contrib/sqlite/load.factor b/contrib/sqlite/load.factor
index ecfc9fd126..2e5fc3920e 100644
--- a/contrib/sqlite/load.factor
+++ b/contrib/sqlite/load.factor
@@ -1,9 +1,7 @@
-IN: scratchpad
-USING: kernel alien parser compiler words sequences ;
+USING: alien ;
 
 "sqlite" "libsqlite3" add-simple-library
 
-{
-    "sqlite"
-    "tuple-db"
-} [ "/contrib/sqlite/" swap ".factor" append3 run-resource ] each
+PROVIDE: sqlite
+{ "sqlite.factor" "tuple-db.factor" }
+{ "tuple-db-tests.factor" } ;
diff --git a/contrib/units/load.factor b/contrib/units/load.factor
index c1b7f04c1a..ffd3d2ef11 100644
--- a/contrib/units/load.factor
+++ b/contrib/units/load.factor
@@ -1,8 +1,2 @@
-IN: scratchpad
-USING: kernel parser sequences words compiler ;
-
-{ 
-    "dimensioned"
-    "si-units"
-    "constants"
-} [ "/contrib/units/" swap ".factor" append3 run-resource ] each
+PROVIDE: units
+{ "dimensioned.factor" "si-units.factor" "constants.factor" } ;
diff --git a/contrib/x11/load.factor b/contrib/x11/load.factor
index aa73f2e3ec..459c21b1ad 100644
--- a/contrib/x11/load.factor
+++ b/contrib/x11/load.factor
@@ -1,6 +1,5 @@
-USING: kernel parser words compiler sequences ;
+REQUIRE: concurrency ;
 
-! contrib/x11 depends on contrib/concurrency
-
-{ "rectangle" "x" "draw-string" "concurrent-widgets" "gl" }
-[ "/contrib/x11/" swap ".factor" append3 run-resource ] each
\ No newline at end of file
+PROVIDE: x11 {
+    "rectangle.factor" "x.factor" "draw-string.factor" "concurrent-widgets.factor" "gl.factor"
+} ;
\ No newline at end of file
diff --git a/library/bootstrap/boot-stage1.factor b/library/bootstrap/boot-stage1.factor
index 22909e9316..6da03f9141 100644
--- a/library/bootstrap/boot-stage1.factor
+++ b/library/bootstrap/boot-stage1.factor
@@ -117,6 +117,7 @@ vectors words ;
         
         "/library/test/test.factor"
 
+        "/library/modules.factor"
         "/library/threads.factor"
         
         "/library/io/server.factor"
diff --git a/library/modules.factor b/library/modules.factor
new file mode 100644
index 0000000000..2e58c7287c
--- /dev/null
+++ b/library/modules.factor
@@ -0,0 +1,49 @@
+! Copyright (C) 2006 Slava Pestov.
+! See http://factorcode.org/license.txt for BSD license.
+IN: modules
+USING: hashtables io kernel namespaces parser sequences words ;
+
+TUPLE: module name files tests ;
+
+: module-path ( name -- path )
+    "/contrib/" swap append ;
+
+: module-paths ( name seq -- seq )
+    >r module-path r> [ "/" swap append3 ] map-with ;
+
+C: module ( name files tests -- module )
+    [ >r >r over r> module-paths r> set-module-tests ] keep
+    [ >r dupd module-paths r> set-module-files ] keep
+    [ set-module-name ] keep ;
+
+: module-def ( name -- path )
+    module-path dup ".factor" append dup resource-path exists?
+    [ nip ] [ drop "/load.factor" append ] if ;
+
+SYMBOL: modules
+
+H{ } clone modules set-global
+
+: module modules get hash ;
+
+: require ( name -- )
+    dup module [
+        drop
+    ] [
+        "Loading module " write dup write "..." print
+        module-def run-resource
+    ] if ;
+
+: run-resources ( seq -- )
+    bootstrapping? get
+    [ parse-resource % ] [ run-resource ] ? each ;
+
+: load-module ( module -- ) module-files run-resources ;
+
+: provide ( name files tests -- )
+    <module> dup load-module
+    dup module-name modules get set-hash ;
+
+: reload-module ( name -- ) module load-module ;
+
+: test-module ( name -- ) module module-tests run-resources ;
diff --git a/library/syntax/parse-syntax.factor b/library/syntax/parse-syntax.factor
index f241502ac1..8d9c7fd235 100644
--- a/library/syntax/parse-syntax.factor
+++ b/library/syntax/parse-syntax.factor
@@ -4,7 +4,7 @@
 ! Bootstrapping trick; see doc/bootstrap.txt.
 IN: !syntax
 USING: alien arrays errors generic hashtables kernel math
-namespaces parser sequences strings syntax vectors words ;
+modules namespaces parser sequences strings syntax vectors words ;
 
 : (
     CHAR: ) column [
@@ -69,3 +69,10 @@ DEFER: PRIMITIVE: parsing
     [ define-constructor ] f ; parsing
 
 : FORGET: scan use get hash-stack [ forget ] when* ; parsing
+
+: PROVIDE:
+    scan [ { { } { } } append first2 provide ] f ; parsing
+
+: REQUIRE:
+    string-mode on
+    [ string-mode off [ require ] each ] f ; parsing