use strings as values, with option to allow removing

TODO.txt

@@ -1,13 +1,9 @@
 * assign types to properties
-  - modifications to types don't commute the same way
-  - optimize this to simplify the transform function
-  - types:
-    - dependencies: set of uuids
-    - annotations: set of annotations (incl timestamps for uniqueness)
-    - tags: set of tags
-  - idea: Update takes a dotted path for property; store everything as a map
-    e.g., {uuid: true}, {timestamp: annotation}, {tag: true}; keep the
-    set-to-null-to-delete to remove
+  - db / operation model is just k/v, but formatted names can be used for
+    structure:
+    - dependencies: `dependency.<uuid> = ""`
+    - annotations: `annotation.<epoch time> = "annotation"`
+    - tags: `tags.<tag> = ""`
 * add HTTP API
 * implement snapshot requests
 * implement backups
@@ -16,3 +12,4 @@
   - need to be sure that create / delete operations don't get reversed
 * cli tools
 * prop testing for DB modifications
+  - 'strict' mode to fail on application of any nonsense operations