---
title: "Theo Browne"
description: "Theo Browne discusses broader software work and model reliability in public talks."
plain: "Theo Browne talks about wider software work and why a model's ordinary reliability matters."
group: person
terms:
  - "Theo Browne"
sources:
  - url: https://youtu.be/xUnRQ9vLXxo
    title: "Everything we knew about software has changed — Theo Browne, @t3dotgg ​ - YouTube"
    publisher: "Theo Browne"
    note: "World's Fair talk; used for wider software work and extensible products."
    accessed: "2026-10-01"
  - url: https://youtu.be/iBrAWpjXNxs
    title: "Please stop using stupid models - YouTube"
    publisher: "Theo Browne"
    note: "Model discussion; used for the reliability floor on long agent runs."
    accessed: "2026-10-01"
  - url: https://youtu.be/TV6f2weVgCI
    title: "It's Time To Rethink Everything by @t3dotgg - YouTube"
    publisher: "Theo Browne"
    note: "CascadiaJS talk; used for rethinking assumptions and building bigger."
    accessed: "2026-10-01"
---

# Theo Browne

> For agents: start with the [agent guide](https://ratstack.sh/llms.txt). Every page is Markdown by default; add `Accept: text/html` for HTML.

New on /news: [Effect Office Hours 52 with Resonate HQ](/news).

Theo distinguishes product breadth from feature depth and describes how extension points, interfaces for adding features, let users build missing features. [AI Engineer World's Fair, 13:23](https://youtu.be/xUnRQ9vLXxo?t=803) [14:37](https://youtu.be/xUnRQ9vLXxo?t=877).

He argues that a model's ordinary reliability matters more than its best result when agents work on longer tasks. [Please stop using stupid models, 04:19](https://youtu.be/iBrAWpjXNxs?t=259).

## Sources

1. [Everything we knew about software has changed — Theo Browne, @t3dotgg ​ - YouTube](https://youtu.be/xUnRQ9vLXxo)
   Theo Browne. World's Fair talk; used for wider software work and extensible products. Accessed 2026-10-01.

2. [Please stop using stupid models - YouTube](https://youtu.be/iBrAWpjXNxs)
   Theo Browne. Model discussion; used for the reliability floor on long agent runs. Accessed 2026-10-01.

3. [It's Time To Rethink Everything by @t3dotgg - YouTube](https://youtu.be/TV6f2weVgCI)
   Theo Browne. CascadiaJS talk; used for rethinking assumptions and building bigger. Accessed 2026-10-01.

## Lore on this page

- [Think wider](/lore/think-wider)

## Linked from

- Agent guide → An Effect stack so pure (aspirational) Kit Langton will blush. → [Read page](https://ratstack.sh/llms.txt)

- Change log → What changed in the files served here, newest first. → [Read page](https://ratstack.sh/log)

- Full agent guide → An Effect stack so pure (aspirational) Kit Langton will blush. → [Read page](https://ratstack.sh/llms-full.txt)

- Rat Stack lore | rat-stack → Short, source-grounded notes on the ideas and decisions behind rat-stack. → [Read page](https://ratstack.sh/lore)

- Source change history (log.md) → The generated change log as Markdown. → [Read page](https://ratstack.sh/log.md)

- Think wider → Theo Browne asks developers to cover more product breadth instead of adding depth in one narrow area. → [Read page](https://ratstack.sh/lore/think-wider)