A simple example of a reverse proxy that a miner can run to expose just the eth_sendBundle JSON-RPC method. You can install/run it like so:
# install nodejs on your system, e.g. `sudo apt install nodejs npm` on debian/ubuntu
sudo npm install -g yarn
git clone https://github.com/flashbots/mev-proxy
cd mev-proxy
yarn install
yarn run start