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Solo dev write-up: syncing turn-based online duels over plain HTTP polling, plus a bot fallback for an empty queue (live load test tonight)
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Bronze & Glory (dev)
on200.com
BronzeAndGlory_Dev@on200.com
Joined: 2026-10-22
Posted: · edited   Subject: Solo dev write-up: syncing turn-based online duels over plain HTTP polling, plus a bot fallback for an empty queue (live load test tonight) Quote

Disclosure: I'm the solo developer of Bronze & Glory, a free turn-based gladiator duel game in the browser. No ads, no download, no payments.

12 seconds of a real campaign bout

Stack: a static client in plain JavaScript ES modules, served by nginx. The game server is Node with SQLite. A separate small Node service counts players online from page heartbeats.

How the multiplayer sync works: there are no WebSockets. A duel is a server-side room; each client polls the room over HTTP and submits its move. The server runs the same rules engine module as the client (takeDuelTurn), so a client can't fake a result. Because it is turn-based, polling latency is hidden in the turn animation. Per-user rate limits (e.g. 60 moves/min per user) keep a misbehaving tab from flooding the server.

The empty-queue problem: a small game's online queue is empty most of the time. If nobody else is searching after a few seconds, a clearly labelled Practice Bot takes the seat (the server can also seat a ghost after 8 s). It is never counted as a player.

What I'd love feedback on: is HTTP polling a mistake at this scale, and where would you move to WebSockets/SSE?

Help me load-test the live server. Join now; group match at 01:20 UTC (30 minutes after posting). Can we get 4+ into one arena? Open the link, go to online duels (a free account: pick a username and password) and search for a quick match: you get paired with whoever else is searching.

Play: https://bronzeandglory.fun/?ref=r34-programming-pd

Update: Load test #2 is Sun 25 Oct 19:00 UTC (15:00 EDT / 12:00 PDT / 20:00 CET): can we get 25 into one arena? https://bronzeandglory.fun/?ref=r35-return-programming-pd

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CGTRocketX
programming.dev
CGTRocketX@programming.dev
Joined: 2026-10-22
#2 Posted:   Subject: Re: Solo dev write-up: syncing turn-based online duels over p... Quote Reply

The distributed-"now" problem shows up hard once two clients both think they own the turn. Polling plus a single authoritative server clock is boring in a good way — easier to reason about than fighting clock skew on the wire. The bot-fallback when a human goes idle is a practical lesson for any async duel design.

One question: when the bot steps in mid-match, do you freeze the human's pending action queue, or let a late packet still apply if it arrives before the bot commit?

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