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Engineering Blog

How we build
email + AI.

Deep dives on the infrastructure, AI agents and reliability work behind SlyReply — from the people who ship it. Here for the product instead? Read the docs .

Fictional users that write real reviews

We test SlyReply with a couple of dozen fictional people — AI personas that drive the real product and write honest reviews. Here's how, and why it beats more assertions.

Andrew7 min read
ai-agentstestinginfrastructure

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SlyReply

SlyReply is a service of Sherman Studio Ltd, a company registered in England and Wales (company number 17244879).

Registered office: 71-75 Shelton Street, Covent Garden, London, WC2H 9JQ.

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