Hi I'm the creator! Not open source yet but that's the plan. Already have data dump implemented for admins, might open that up too. Happy to have contributions to add more cities. Right now the sticking point is getting API keys... Because a lot of cities like New York and Chicago have systems but they also restrict access.... Honestly not sure how to get more API keys more quickly but probably local people on the ground would help.
Dm your GitHub and I can add you!