[330 Cities, One Decision: PoPs and Smart Placement]
300+ PoPs plus Smart Placement: anycast ingress, compute migrates toward exchange API proximity—not co-lo.
Sources: papers/sections/04-mechanisms.tex, 02-background.tex, 14-runtime-semantics.tex, ADR notes, listing wrangler-hoox-placement.jsonc, edge-architecture docs.
Thesis
Trading latency is mostly geography wearing a software costume. HOOX does not rent a rack next to a matching engine. It runs on 300+ Cloudflare PoPs and lets Smart Placement move compute toward the outbound dependency that dominates order time: the exchange REST API.
Hop budgets and measurement honesty: essay 06.
1. What a PoP is (HOOX terms)
A Point of Presence is where anycast lands public traffic, V8 isolates execute, Service Bindings ride the private fabric, and outbound fetch leaves toward exchange origins. Cold starts: sub-3 ms class. A PoP is not exchange co-lo—it is the best-peered Cloudflare city for your signing code’s HTTPS to the venue.
2. Three notions of “nearest”
| Question | Nearest means | HOOX choice |
|---|---|---|
| Webhook entry? | PoP near TradingView (anycast) | Free with global edge |
Where should trade-worker run? |
PoP with best RTT to exchange origin | Smart Placement on |
Where should dashboard SSR run? |
PoP near browsers | Smart Placement off |
Ingress optimizes stage 1. Placement optimizes the signed outbound leg.
3. Smart Placement mechanism
Cloudflare continuously measures RTT from PoPs to a Worker’s outbound origins and migrates isolate execution to minimize that RTT.
"placement": { "mode": "smart" }
Enabled: hoox, trade-worker, d1-worker, agent-worker.
Disabled: dashboard.
Invocation/migration cost is lifecycle-class; for a stream of signals, marginal cost is the optimized outbound leg. Peering to venues can land in single-digit milliseconds when the network cooperates.
4. Bindings across PoPs
Fear: hoox in London, trade-worker near Frankfurt-peered Bybit—is the mesh slow?
Answer: Service Bindings use the private fabric, not the public internet—still sub-millisecond across PoPs. The split is intentional:
TV ──anycast──► PoP_A (hoox)
│ private fabric
▼
PoP_B (trade-worker, smart-placed)
│ short public HTTPS
▼
Exchange API
5. PoP vs VPS
| Fixed VPS | Edge + Smart Placement |
|---|---|
| One region forever | 300+ PoPs; compute migrates |
| Outbound 80–200 ms common | Outbound optimized toward venue peering |
| You pick the city | Platform measures origins continuously |
| Idle always on | Pay-per-request; free tier viable for retail |
Production headline: ~22 ms median signal-to-ack (direct path)—Smart Placement is a core ingredient of the outbound story, not a checkbox.
6. Myths
| Myth | Reality |
|---|---|
| Every request runs in all 330 cities | Placement, not global fan-out of business logic |
| Ingress PoP always equals execution PoP | Anycast and smart placement can diverge |
| Placement replaces WS amortization | Complementary (essay 11) |
| Dashboard should smart-place | HOOX disables it |
Related: Latency race · Bindings · Edge thesis · Enterprise