tag: deep dive

6 posts

all identity pipeline flags sdk replay deep dive product

24 Jul 2026 · 6 min read

Product tours that survive your next deploy

Every tour tool asks you for a CSS selector, then quietly breaks when your markup changes. We built the picker, the preview and the alarm — and the interesting part is the ranking that decides which selector to hand you.

sdk deep dive

11 Jul 2026 · 5 min read

Trust, but verify: making distinct_id spoof-proof

Open devtools on almost any product and you can become its CEO — as far as analytics is concerned. Here's the boring cryptography that closes the hole, and the surprisingly delicate question of what to do with events that fail.

identity deep dive

24 Jun 2026 · 6 min read

One door in: why every event takes the same path

Fifteen years of building products leave you with scars, and ours all share an origin: data that entered a system through more than one door. This is the story of why Kilden only has one.

pipeline deep dive

Many tangled glowing paths converging into a single luminous doorway and emerging as ordered parallel lanes

13 May 2026 · 3 min read

Kafka never carries blobs: session replay as a claim check

For a while, some of our session replays played back as minutes of black screen. The recordings were fine. The bug was in a filename — and the fix is a rule about key design worth stealing.

replay pipeline deep dive

29 Apr 2026 · 3 min read

One pipeline, four products

Your analytics tool and your email tool disagree about what a user did today. Only one of them is wrong — good luck finding out which. Kilden's answer is structural: four products that physically cannot disagree, because they read the same stream.

pipeline deep dive

15 Apr 2026 · 3 min read

Exactly-once-ish: the delivery guarantees we actually promise

Ask a queue vendor for exactly-once delivery and watch the asterisks multiply. It doesn't exist — but exactly-once effects do, and the whole trick is three decisions about where duplicates go to die.

pipeline deep dive

$ npm install kilden

Build your data pipeline in two minutes

Analytics, feature flags, campaigns and session replay — one event pipeline, one SDK. Free to start.

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