TowerPanic: a family party game in your browser

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I want to show you the game I created recently and tell you whole the story/experience - including backend/latency/scalability.You can try it quickly without an account - I created game demo rooms (EU/US/JP) - links below - just be aware that anyone with a link can access join the game.Let's start with short description of the game itself:This is the TowerPanic game - you are standing on one of four towers, during each round some of towers crack, and some of these lean, and finally one of these colapse - you need to watch out to not be on the failing one. It's a multiplayer game for whole family. This can be also used as an icebreaking game - for people in any age. The game is safe for children - no violence, no strangers, no chat, no ads. Parent creates an account (free 14-day trial, then a paid pass) and starts the game - others join using a QR code or a link.Behind the game there is an interesting backend engine - I willdescribe it in a moment.Let's start with the history of this whole project: - I was playing with asyncio and fastapi - As an exercise I created a reliable chat application (multiple rooms, in each room each user can reliably broadcast a message to all other users) - I extracted communication to separate layer - creating network/application layer interfaces - 'reliable client' interface for client and 'state machine' interface for the service on server. - With these interfaces - I was able to create other service - an 'sgame' (simple game). With verified interfaces and created services (chat, sgame) I was able to ask AI to generate other tools/games - I was impressed by these results - the games/tools worked well - I deployed them on a remote server - I was surprised that the latency was very good - almost everything worked smoothlyI tested the tools and games with my children and one of the game was really great. I decided to make this game public - I chose 'TowerPanic' name for it.I prepared an account/payment server for this game (as a separate FastAPI application). This was very good choice: - the game servers keep rooms only in memory - nothing persistent (rooms have expiration date) - the account server keeps all persistent data (it uses database)Because of this split I was able to figure out how to upgrade and scale frontend and backend independently - without significantly impacting users.I optimized the communication layer - so that it works in finite memory - only finite number of recent messages is kept, and I sent a full service snapshot (full state) to the lagging clients.The backend process (FastAPI/python) is limited by python GIL (only one core can be utilized) - to utilize all server cores I used HAProxy with consistent hashing to distribute rooms - so that users can be redirected to proper backend process.I tested how many rooms a single server can handle - it handles hundreds of active rooms in parallel with no significant latency drop.Before making it public I noticed that latency in other region of world might be higher and this could influence UX - I confirmed this using artificial delay on my remote server.I decided to deploy the application in three regions - EU, US, JP - to ensure low latency (below 150ms) in most of the world. The room is created in region closest to the user (best latency from the browser to backend).I needed also to prepare some legal documents (terms, privacy, refunds) - thanks to AI this was much easier. I'm a backend engineer, frontend/UI/UX were designed by me but code was generated by AI.To summerize all this work: - I'm happy that I was able to deliver complete game/complete product - I think the whole work took me about 20 evenings - I'm impressed that it was so short - I think this is because the technology I used is popular and all fits well - AI was great as a peer (to discuss the options for distributing the load, discuss were to locate servers, or discuss how auth/payments work under the hood, ... - based on this I could choose the best option) - AI was great for doing the non work which I'm doing ineffectively (frontend/UI/legal docs).The game is available at https://towerpanic.com/?ref=hnI will appreciate your comments/feedback:Product: - did you meet any obstacles to play ? - how smoothly it worked ? - please specify your location if it didn't work well - most important thing/things to improve ? - anything else ... Solution/Engineering: - one thing you will change in the architecture / approach ? - anything else ...If you don't want to register you can play directly using below links (2 rooms for each location, max 10 players in each room/board). Choose best location:DEMO ROOMS (expire: 19 October 2026 at 22:00 UTC):EU: https://engine.prod-de-1.towerpanic.com/b/hn1/join/AUB3lS3Y_... https://engine.prod-de-1.towerpanic.com/b/hn4/join/ASlA3J43U...US: https://engine.prod-us-1.towerpanic.com/b/hn2/join/AUCCS_x9d... https://engine.prod-us-1.towerpanic.com/b/hn5/join/AVQbs_01N...JP: https://engine.prod-jp-1.towerpanic.com/b/hn3/join/Afj600qp5... https://engine.prod-jp-1.towerpanic.com/b/hn6/join/AUpDUuB1W...