I have the privilege to help DFINITY with the task of (re)developing the Network Nervous System (NNS) frontend dapp.
The NNS is the controlling mechanism by which the Internet Computer’s nodes and subnets are organized, tracked, and managed.
It is also the web application that holders of the Internet Computer’s ICP utility tokens can use to lock their tokens in neurons in order to participate in governance and to contribute to decision-making (find more about NNS in this post).
Infrastructure: 100% on chain Internet Computer
The projects of the foundation are open source. Those to which I collaborate the most on GitHub are nns-dapp and ic-js.