diff --git a/functional-tests/thin/mapping-tree.scm b/functional-tests/thin/mapping-tree.scm
deleted file mode 100644
index 3918469..0000000
--- a/functional-tests/thin/mapping-tree.scm
+++ /dev/null
@@ -1,40 +0,0 @@
-(library
-  (thin mapping-tree)
-
-  (export mapping-tree-lookup
-          mapping-tree-each)
-
-  (import (persistent-data btree)
-          (bcache block-manager)
-          (chezscheme)
-          (srfi s8 receive))
-
-  ;; (values <block> <time>)
-  (define time-mask (- (fxsll 1 24) 1))
-
-  (define (unpack-block-time bt)
-    (values (fxsrl bt 24) (fxlogand bt time-mask)))
-
-  ;; FIXME: unpack the block time
-  (define (mapping-tree-lookup cache root dev-id vblock default)
-    (with-spine (sp cache 1)
-      (let* ((unique (gensym))
-             (dev-tree (btree-open le64-vt root))
-             (root2 (btree-lookup dev-tree sp dev-id unique)))
-            (if (eq? unique root2)
-                default
-                (btree-lookup (btree-open le64-vt root2) sp vblock default)))))
-
-  ;;; Visits every entry in the mapping tree calling (fn dev-id vblock pblock time).
-  (define (mapping-tree-each cache root fn)
-          (with-spine (sp cache 1)
-            (let ((dev-tree (btree-open le64-vt root)))
-
-             (define (visit-dev dev-id mapping-root)
-                     (btree-each (btree-open le64-vt mapping-root)
-                                 (lambda (vblock mapping)
-                                   (receive (block time) (unpack-block-time mapping)
-                                     (fn dev-id vblock block time)))))
-
-             (btree-each dev-tree sp visit-dev))))
-  )
diff --git a/functional-tests/thin/metadata.scm b/functional-tests/thin/metadata.scm
index 60569d3..afc36b9 100644
--- a/functional-tests/thin/metadata.scm
+++ b/functional-tests/thin/metadata.scm
@@ -2,54 +2,100 @@
   (thin metadata)
 
   (export ThinSuperblock
-          ThinDeviceDetails)
+          ThinDeviceDetails
+
+          block->superblock
+
+          mapping-tree-lookup
+          mapping-tree-each
+          unpack-block-time
+
+          device-tree-lookup
+          device-tree-each)
 
   (import (chezscheme)
           (bcache block-manager)
-          (persistent-data btree))
+          (persistent-data btree)
+          (srfi s8 receive))
 
   (define $superblock-magic 27022010)
   (define $superblock-salt 160774)
   (define $uuid-size 16)
   (define $space-map-root-size 128)
 
-  (define-compound-value-type device-details-vt ThinDeviceDetails)
-
   (define (block->superblock b)
           (make-ftype-pointer ThinSuperblock (block-data b)))
 
   (define-ftype ThinSuperblock
-                (packed
-                  (endian little
-                          (struct
-                            (csum unsigned-32)
-                            (flags unsigned-32)
-                            (block-nr unsigned-64)
-                            (uuid (array 16 unsigned-8))
-                            (magic unsigned-64)
-                            (version unsigned-32)
-                            (time unsigned-32)
-                            (trans-id unsigned-64)
-                            (metadata-snap unsigned-64)
-                            (data-space-map-root (array 128 unsigned-8))
-                            (metadata-space-map-root (array 128 unsigned-8))
-                            (data-mapping-root unsigned-64)
-                            (device-details-root unsigned-64)
-                            (data-block-size unsigned-32)
-                            (metadata-block-size unsigned-32)
-                            (metadata-nr-blocks unsigned-64)
-                            (compat-flags unsigned-32)
-                            (compat-ro-flags unsigned-32)
-                            (incompat-flags unsigned-32)))))
+    (packed
+      (endian little
+              (struct
+                (csum unsigned-32)
+                (flags unsigned-32)
+                (block-nr unsigned-64)
+                (uuid (array 16 unsigned-8))
+                (magic unsigned-64)
+                (version unsigned-32)
+                (time unsigned-32)
+                (trans-id unsigned-64)
+                (metadata-snap unsigned-64)
+                (data-space-map-root (array 128 unsigned-8))
+                (metadata-space-map-root (array 128 unsigned-8))
+                (data-mapping-root unsigned-64)
+                (device-details-root unsigned-64)
+                (data-block-size unsigned-32)
+                (metadata-block-size unsigned-32)
+                (metadata-nr-blocks unsigned-64)
+                (compat-flags unsigned-32)
+                (compat-ro-flags unsigned-32)
+                (incompat-flags unsigned-32)))))
 
   (define-ftype ThinDeviceDetails
-                (packed
-                  (endian little
-                          (struct
-                            (mapped-blocks unsigned-64)
-                            (transaction-id unsigned-64)
-                            (creation-time unsigned-32)
-                            (snapshotted-time unsigned-32)))))
+    (packed
+      (endian little
+              (struct
+                (mapped-blocks unsigned-64)
+                (transaction-id unsigned-64)
+                (creation-time unsigned-32)
+                (snapshotted-time unsigned-32)))))
 
+  ;; (values <block> <time>)
+  (define time-mask (- (fxsll 1 24) 1))
+
+  (define (unpack-block-time bt)
+    (values (fxsrl bt 24) (fxlogand bt time-mask)))
+
+  ;; FIXME: unpack the block time
+  (define (mapping-tree-lookup cache root dev-id vblock default)
+    (with-spine (sp cache 1)
+      (let* ((unique (gensym))
+             (dev-tree (btree-open le64-vt root))
+             (root2 (btree-lookup dev-tree sp dev-id unique)))
+            (if (eq? unique root2)
+                default
+                (btree-lookup (btree-open le64-vt root2) sp vblock default)))))
+
+  ;;; Visits every entry in the mapping tree calling (fn dev-id vblock pblock time).
+  (define (mapping-tree-each cache root fn)
+          (with-spine (sp cache 1)
+            (let ((dev-tree (btree-open le64-vt root)))
+
+             (define (visit-dev dev-id mapping-root)
+                     (btree-each (btree-open le64-vt mapping-root)
+                                 (lambda (vblock mapping)
+                                   (receive (block time) (unpack-block-time mapping)
+                                     (fn dev-id vblock block time)))))
+
+             (btree-each dev-tree sp visit-dev))))
+
+  (define-compound-value-type device-details-vt ThinDeviceDetails)
+
+  (define (device-tree-lookup cache root dev-id default)
+          (with-spine (sp cache 1)
+            (btree-lookup (btree-open device-details-vt root) sp dev-id default)))
+
+  (define (device-tree-each cache root fn)
+          (with-spine (sp cache 1)
+            (btree-each (btree-open device-details-vt root) sp fn)))
   )