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Nothing fires twice: idempotency for business automations
Webhooks deliver at least once and people click twice. The habits that stop an automation creating two jobs, two invoices, or two emails.
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Three prices, one truth
The same job priced three different ways by the same business, nearly two thousand pounds apart. How to find your own quiet disagreements.
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Accounting APIs lie politely
Cumulative columns, forecasts dressed as fact, and a token refresh that logs everyone out. Three traps in cloud accounting APIs.
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Spotify's agent playbook, at 30 people
Spotify merged 2.5 million AI-written pull requests behind standardisation, context and verification gates. The miniature version holds up.
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Your staging site is trying to poison your SEO
A daily check caught a staging host that had quietly stopped saying noindex. The four-line defence that keeps staging out of Google.
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How to evaluate a RAG system before you trust it
Retrieval-augmented generation demos beautifully and fails quietly. The evaluation loop that says whether a system is good before it reaches a user.
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More field notes on the way — each one ends with something you can run.