Packet Run, for grown-ups
A short roguelite where your child plays the spirit of a message — five packet-fragments crossing the internet to reach someone they love. One run takes 5–10 minutes on a phone. Everything below is what's really going on under the story.
What it actually teaches
| In the game | On the real internet |
|---|---|
| The message splits into 5 fragments | Packet switching — data travels as independent packets |
| Fragments race and arrive shuffled | Packets take different routes and arrive out of order |
| The Deadline clock | Latency budgets — late data can be as bad as lost data |
| Duplicate & Retransmit | Redundancy and retransmission — how reliability is built, not assumed |
| Checksum & Repair vs the Static | Error detection — receivers checksum every packet and drop what fails; retransmission fills the gap. The game's Repair stands in for restoring the bits, which real systems do by retransmitting — or sometimes with forward error correction |
| The birthday message vs the live call | TCP vs UDP by feel: every-piece-matters vs keep-it-moving (named only after Act 5). Strictly: UDP just doesn't promise delivery — the calling app decides whether to skip late frames, and that choice was your kid's all along |
| The address book beat | DNS lookups, and why caching makes the second visit faster |
| The jammed pipe's send-rate choice | Congestion control — slow start and backing off, by feel |
| The Encryption Cloak | Encryption in transit: visible on the wire but unreadable — it never hides the route. (The game's sniffer also tampers; strictly, a watcher who alters data is an on-path attacker — real packet sniffers just watch) |
| The cache waystation shortcut | CDNs — a copy served from somewhere closer |
| The swarm that starves a pipe | DDoS — floods exhaust shared capacity; rate-limiting is triage |
| The Far Reaches' sparse grid | The digital divide — underinvestment in infrastructure, never a fault of the people there |
The accuracy promise
The design rule is: never teach a falsehood. Simplify, dramatize, personify — but never plant an idea that has to be unlearned later. Some commitments that shaped the game:
Fragments never travel as an in-order convoy — the racing, shuffled arrival is the lesson.
Packets never walk backwards. What looks like a retreat is the sender reissuing — because that's what really happens.
Encryption makes data unreadable, not invisible. The sniffer still sees sealed fragments pass; it just learns nothing.
Losses end with an honest autopsy: what struck, which idea beat you, which tool answers it, and one line about how the real internet handles the same problem.
Using it together
- Let them lose. The loss screen teaches more than the win screen — ask "what got you?" and they'll explain packet loss to you.
- Ask about the two payloads. "Why do you skip fragments on a call but never for the message?" is the whole TCP/UDP distinction, in their own words.
- Play the daily run against each other. Same seed, same map — different choices. Compare lines.
- Watch for the Act 5 reveal. After the final boss the game names TCP and UDP — the vocabulary lands on top of felt experience, not instead of it.
Privacy
No accounts, no tracking, no analytics, no ads, nothing leaves the device. Progress (wins, settings, run history) lives in the browser's local storage only. Share cards are plain text your child chooses to copy — they contain a map seed, never personal data.