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 # µMatrix for Chromium
 
-[Under development: unusable]
+[Under development: usable, but persistence schema not finalize, will certainly change]
+
+Forked from [HTTP Switchboard](https://github.com/gorhill/httpswitchboard).
+
+Differences with HTTP Switchboard:
+
+- No pattern-based filtering -- use more advanced [µBlock](https://github.com/gorhill/uBlock) for this
+- Rules from broader scopes propagate to narrower scopes
+    - This means rules in global scope are ubiquitous, i.e. no longer sandboxed
+    - See matrix as really 3D: evaluation order: Z, then X and Y, where
+        - Z is the source hostname axis (aka "scope"), from global scope to narrower scopes
+        - X is the request type axis: `*`, `cookie`, `css`, etc.
+        - Y is the destination hostname axis (`www.example.com`, `example.com`, `com`, `*`
+- Much needed [code refactoring](http://en.wikipedia.org/wiki/Code_refactoring) toward portability/efficiency
+    - Big chunks of tired code have been removed, or replaced by small chunks of better code
+    - There is no longer a hierarchical data structures for scopes/rules (**major** contribution toward code simplification)
+    - Thus no need to manage the creation/deletion of scopes (and related settings)
+    - All scopes virtually exist at all time.
+    - The popup matrix simply activate whatever last scope level was in use
 
 ## License