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I spent $20,000 on Devin in a month. Here’s what I learned | Ryan Carson (solo founder)

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Summary (from the publisher)

Watch now | 🎙️ Solo founder Ryan Carson runs 15 concurrent Devin agents to handle engineering, customer success, and investor updates, and he uses a handwritten list to keep it all straight

Ryan Carson is a five-time founder and the current solo founder of Untangle, a B2B SaaS platform for family law firms. Before Untangle, he co-founded Treehouse, an online coding education platform, and has spent the better part of two decades building and leading tech companies. He’s active on X, where he shares his solo founder journey in real time, including what he actually spends on AI tools each month.

Why Ryan manages 15 concurrent Devin agents with a folder system and a piece of paper, not a dashboard

The Watchdog playbook: what he built to replace a customer success team across every law firm account

How his LAN PR skill closes the loop on 40 daily PRs without a QA team reviewing a single one

Why he moved off local agents almost entirely, and the one situation where he still reaches for Codex

The design workflow we’re both using: Claude Design into a Markdown spec, then Codex to build the real thing

What he found when he got away from his computer and met a real customer, and why it changed his entire product direction

How he’s hiring his first engineer without a single phone screen or interview

Why we both think more AI output is actually the wrong goal, and what to optimize for instead

WorkOS—Make your app enterprise-ready, with SSO, SCIM, RBAC, and more

(02:55) Ryan’s update: Untangle, the divorce PMF pivot, and B2B growth

(07:35) Ryan’s current Devin stack: folders, P0 threads, and the paper list

(16:29) Watchdog playbook: account monitoring across every firm

(18:09) Managing agent decision fatigue: Ryan’s method vs. Claire’s

(20:32) Producing more output does not make a better product

(28:15) LAN PR skill: review loops, video walkthrough, and auto-merge

(30:20) Slack vs. Devin threads for async team communication

(35:58) Claude Design plus Codex for building a technical design system

(39:00) EA tools: Polly the OpenClaw vs. Claude Code on a Mac Mini

• Claude Code/Claude Design (Anthropic): https://www.anthropic.com/claude

• OpenClaw (Claude-based desktop client): https://openclaw.ai

• BugBot (Devin’s built-in PR review): https://cursor.com/bugbot

• Sentry (error monitoring referenced in Watchdog): https://sentry.io/

• Devin playbooks/skills documentation: https://docs.cognition.ai/

• Jack Dorsey/Buzz (async-first communication referenced): https://buzz.new/

• Merge Mommy (Claire’s Eve agent for PR risk scoring, deployed on Vercel): https://www.lennysnewsletter.com/p/build-an-ai-code-review-bot-in-30

Read the original at lennysnewsletter.com