An Inside Look at Building an Email Client in 3 Months - Ep. 44 with Kieran Klaassen, Brandon Gell

Building an email client used to take many years and millions of dollars.

But Every’s Kieran Klaassen built Cora—a totally new way to manage your inbox with AI—in just 3 months. He even shipped the original MVP of the product in a single day—something that just wasn’t possible before the current state of generative AI.

Now, there are almost 10,000 people on the waitlist for Cora, and we’re onboarding new users every single day.

Every’s head of Studio Brandon Gell and I worked closely with Kieran as he built Cora, and to kick off my podcast, AI and I, in 2025, I invited both of them on the show to talk about it. We go behind the scenes, getting into:

• How Kieran built the product with Cursor, o1, and o1 Pro

• What we’re learning as we onboard new users every day

• The future of Cora and of Every as a multi-modal media company

This is a must watch for anyone curious about our approach to building with AI at Every.

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Timestamps:

1. Introduction: 00:01:56

2. How the maker of Cora describes the product: 00:02:33

3. Our first mistake while building Cora: 00:06:31

4. The story of how Kieran shipped the first MVP overnight: 00:09:37

5. Why Dan believes software is becoming content: 00:13:44

6. Products with a point of view will win: 00:16:40

7. How Kieran approaches building a new product: 00:19:16

8. Best practices while using Cursor: 00:31:55

9. Hacking together a copy editor in Cursor live on the show: 00:41:05

10. The future of Cora, and the hardest challenge we face today: 00:53:58