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+# CircuitMatter
+
+CircuitMatter is a Python-only implementation of the Matter IOT specification. It is aimed at hobby use and hasn't been certified for commercial use.
+
+The Matter spec originates out of the Connected Home over IP (CHIP) project and some resources still use this naming. Matter is the trademark associated with certification.
+
+## Running CircuitMatter
+
+CircuitMatter is currently developed in CPython 3.12, the de facto implementation written in C. It is designed with minimal dependencies so that it can also be used on CircuitPython on microcontrollers.
+
+After cloning the repo, pip install `ecdsa` and `cryptography`.
+
+### Generate a certificate declaration
+
+Each Matter device has its own certificate to capture whether a device has been certified. (CircuitMatter declares itself as an uncertified test/development/hobby device.) This is referred to the Certificate Declaration (CD). CircuitMatter can generate a CD for you and the remaining certificates are loaded from the projectchip repositorry. The certificate generated by CircuitMatter is signed by a test private key.
+
+To generate a CD run:
+
+python -m circuitmatter.certificates
+
+This will write the `certificate_deeclaration.der` file.
+
+### Running a CircuitMatter replay
+
+CircuitMatter can capture and replay UDP packets and random numbers to ease development. (Currently encryption key generation isn't captured.) You can test the start of the CircuitMatter process by using the replay file from the repo:
+
+python -m circuitmatter test_data/recorded_packets.jsonl
+
+This won't exactly run as a previously captured run but it is still useful.
+
+### Running for real
+
+To run CircuitMatter against a live Matter commissioner run:
+
+python -m circuitmatter
+
+This will start up MDNS via avahi for discovery by the commissioner and then reply to received UDP packets. CircuitMatter currently doesn't fully commission so it can't act as any specific type of device yet. When it can, there will be examples.
+
+## Running a Matter commissioner
+
+The de facto standard implementation of Matter is open source as well. It is written in C++ and has many dependencies. It implements all of the different facets of the specification.
+
+We use this implementation via [ESP Matter](https://github.com/espressif/esp-matter) (tested on commit 9350d9d5f948d3b7c61c8659c4d6990d0ff00ea4) to run an introspectable (aka debug printable) commissioner.
+
+To setup esp-matter clone the repo and load submodules:
+
+git clone -o espressif [email protected]:espressif/esp-matter.git
+cd esp-matter
+git submodule update --init --recursive .
+
+This will pull down the ESP Matter wrapper code and the projectchip implementation into the `connectedhomeip/connectedhomeip/` sub-directory.
+
+To build all of the command line tools run
+
+bash install.sh
+
+(Or source it directly if you use bash.)
+
+Now setup the environment using `export.sh`. (This depends on what shell you use.)
+
+Next, run `chip-tool` to initiate the commissioning process:
+
+chip-tool pairing onnetwork 1 67202583
+
+This will look up commissionable devices on the network via MDNS and then start that process. Logs can be added into the chip sources to understand what is happening on the commissioner side. To rebuild, I've had to run `bash install.sh` again.