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+
+# Contributing
+
+## Generally
+
+Branching is good discipline to get into with multiple people working
+on the same repo for different reasons.
+
+To create a branch...
+
+- `git checkout -b etl` # to create the branch and check it out
+- `git push` # to push the branch head to the upstream repo.  You get an error and a command to run.  You don't have to do this straight away, but I like to get the BS admin out the way.  At this stage your branch HEAD points to the head of main.
+
+## Adding a new module
+
+So, to add a new module...
+
+- It needs a name. Say `kg-mymodule` but you can call it what you like.
+- It also needs a place in the Python package hierarchy, because it's
+  basically going to be its own loadable module.  We have a `trustgraph.kg`
+  module it can be a child of.  So, you need a directory
+  `trustgraph/kg/mymodule`
+- You need three files:
+  - `__init__.py` which defines the module entry point.
+  - Then, `__main__.py` means the module is executable.
+  - Finally a module to contain the code, let's call it `extract.py`.
+    The name doesn't matter but it has to match what's in `__init__.py` and
+    `__main__.py`.
+- The easiest way to get start is maybe make a copy of an existing module.
+- `cp -r trustgraph/kg/extract_relationships trustgraph/kg/mymodule/`
+- Finally you need a script entry point, in `scripts`.  Copy
+  `scripts/kg-extract-relationships` to `scripts/kg-mymodule`
+- In that `kg-mymodule` file, change the import line to import your module,
+  `trustgraph.kg.mymodule`.
+
+## Development testing
+
+To run your module, you don't need to have it running in a container.
+It can connect to Pulsar.
+
+The plumbing for your new module pretty needs to be right.  Look at the
+input_queue, output_queue and subscriber settings near the top of your
+new module code.
+
+So, before changing the code any more, if you copied an existing module,
+check the plumbing works with your renamed module.
+
+To run standalone, it is recommended to take an existing docker-compose
+file, run everything you need except the module you're developing.
+
+Then when you launch with docker compose, you'll get everything running
+except your module.
+
+To run your module, you need to set up the Python environment as you did
+in the quickstart e.g. run `. env/bin/activate` and `export PYTHONPATH=.`
+
+You're not running kg-mymodule in a container, so it can't use docker
+internal DNS to get to the containers, but the docker compose file
+exposes everything to the host anyway.  You should be able to access Pulsar
+on localhost port 6650, for instance.
+
+You should be able to run your module on the host and point at Pulsar thus:
+
+```bash
+scripts/kg-mymodule -p pulsar://localhost:6650
+```
+
+You could try loading data, and check some stuff ends up in the graph.  If you get that far you're ready to hack the contents of extract.py to
+do what you want.
+
+## Structure of the code
+
+The Processor class, `run` method is where all the fun takes place.
+
+```
+        while True:
+            msg = self.consumer.receive()
+```
+
+That bit :point_up: is a loop which is executed every time a new message
+arrives.
+
diff --git a/README.md b/README.development.md
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rename to README.development.md