Why this ranks here. Edge compute is genuinely differentiated experience —
and the constraints are what make it interesting. No TCP sockets, no long-lived state, single-writer Durable
Objects, and a cold-start budget. Every one of those forced a real
architectural decision here.
Ten Workers under four constraints
No TCP sockets, no long-lived state, single-writer Durable Objects, and a cold-start budget. Each of those forced a real design decision rather than a workaround, the outbox in project 1 exists because of the first one.
Plus billboard-gateway-edge — R2 range streaming for audio, with an
/api/* proxy to the Node origin.
The interesting constraint
Workers cannot open raw TCP sockets. Not with a library, not with a shim.
That makes the Kafka wire protocol and CQL permanently unreachable from the
edge.
This is the constraint that produced the Activity Graph's
outbox design: the Worker writes an event row transactionally, and a separate
host-resident Go process relays it into Kafka. The architecture is a direct
consequence of a platform limit, and the design follows from the limit rather than from preference.
Storage primitives, and what each is for
Primitive
Used for
Why not the others
D1 (SQLite)
Relational user/library data
Cheap, transactional, edge-local reads
R2
Audio/video objects, multipart ingest
No egress fees; range requests for streaming
KV
Config, hot lookups
Eventually consistent, so never for anything ordered
Single-writer coordination — the only strong-consistency tool at the edge
Hyperdrive
Pooled Postgres from the edge
Connection pooling that Workers otherwise cannot have
WASM at the edge
JamzFingerprintDO loads kissfft.wasm — an FFT compiled to WebAssembly
to compute audio fingerprint constellations inside a Durable Object. (The
module was referenced but had never been built; building it was commit
e04aaf6fb.) The emsdk/ and chromaprint/ trees in /srv are the
toolchain and reference implementation behind it.
Scope
Metric
Value
Workers
10
Edge TypeScript
~75K lines
Storage primitives
D1, R2, KV, Durable Objects, Hyperdrive
Notable
WASM FFT in a DO; R2 range streaming; multipart ingest