Safehouse Lab
We run a companion platform for Warframe called EchoBorn — world state, open-world cycles, market data, builds, and a community around it. Building it taught us something we now treat as a rule across every project here.
The rule is: if a number can be computed, compute it.
The obvious way, and why we stopped
A companion site is a straightforward idea. The game has publicly readable state. Someone kindly runs an API that exposes it. You fetch, you cache, you render. Everyone in that space does roughly this, and it works right up until it doesn't.
What it does when it doesn't work is the problem. A fetched number has two states a reader cannot tell apart: fresh and stale but still rendering. A page showing a four-hour-old value looks exactly like a page showing a live one. There is no error. Nothing logs. The site is simply, quietly wrong, and the only person who finds out is the player who planned their evening around it.
The open worlds run on arithmetic
The thing is, several of those numbers never needed fetching at all.
The day-night cycles in the game's open zones are not random events announced by a server. They are deterministic schedules. Given a known reference point and the length of a cycle, where you are in that cycle right now is arithmetic — a subtraction and a modulo. The same is true of the vendor rotations. The information is in the shape of the system, not in a feed.
So we wrote an engine that computes all five open-world cycles directly. No request, no key, nothing to rate-limit, nothing that can go stale. It runs in the browser, and it is correct whether or not anything else in the world is up.
Nine hours
That turned out not to be theoretical. The public API that most of this ecosystem depends on went down for roughly nine hours. Sites across the community showed stale values or nothing at all.
Our cycle cards did not notice. They had nothing to notice with.
That is the entire argument for the approach, in one day. The resilience was not a feature we added; it was a consequence of removing a dependency we did not need in the first place.
Say where the number came from
Not everything can be derived. Market prices are prices — real data, from a real feed, and no amount of cleverness computes what someone is willing to pay.
So the second half of the rule is about honesty. Every number on our world state page carries a mark saying where it came from: one glyph for computed, another for live feed. A reader can see at a glance which numbers are arithmetic and which are someone else's data arriving over a wire.
This costs nothing and it changes the relationship. A site that tells you which of its numbers could be stale is a site you can calibrate. One that presents everything with equal confidence is asking you to trust it uniformly, which is exactly the thing it has not earned.
Where else it applies
Once you have the rule, you see it constantly.
Where the sun is above a given city right now is arithmetic — latitude, longitude, date. No weather API required to know whether it is dark in Berlin. Sunrise and sunset, the phase of twilight, the position of a planet: all derivable, all offline, all permanently correct.
Every one of those is a dependency not taken, a key not stored, an outage that cannot reach you, and a number that is right at three in the morning when nobody is watching the dashboard.
Fetch what you genuinely cannot know. Compute the rest. And either way, tell the reader which one they are looking at.