4x4 debugging workflow for unblockers

Lazar Jovanovic is a full-time professional vibe coder at Lovable. His job is to build both internal tools and customer-facing products purely using AI, while not having a coding background. In this conversation, he breaks down the tactics, workflows, and framework that let him ship production-quality products using only AI.

We discuss:

1. Why having no coding background can be an advantage when building with AI

2. Why most of your time should go to planning and chat mode, not prompting

3. What to do when you get stuck: his 4x4 debugging workflow

4. The PRD and Markdown file system that keeps AI agents aligned across complex builds

5. Why kicking off four or five parallel prototypes is the best way to clarify your thinking

6. Why design skills and taste are going to be the most important skills in the future

7. His “genie and three wishes” mental model for making the most of AI’s limitations

8. How product, engineering, and design roles are converging—and what that means for your career

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Episode transcript: https://www.lennysnewsletter.com/p/getting-paid-to-vibe-code

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Archive of all Lenny's Podcast transcripts: https://www.dropbox.com/scl/fo/yxi4s2w998p1gvtpu4193/AMdNPR8AOw0lMklwtnC0TrQ?rlkey=j06x0nipoti519e0xgm23zsn9&st=ahz0fj11&dl=0

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Where to find Lazar Jovanovic:

• X: https://x.com/lakikentaki

• LinkedIn: https://www.linkedin.com/in/lazar-jovanovic

• YouTube: https://www.youtube.com/@50in50challenge

• Starter Story course: https://build.starterstory.com/build/ai-build-accelerator?via=lazar (code LAZAR15 for 15% off)

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Where to find Lenny:

• Newsletter: https://www.lennysnewsletter.com

• X: https://twitter.com/lennysan

• LinkedIn: https://www.linkedin.com/in/lennyrachitsky/

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In this episode, we cover:

(00:00) Introduction to Lazar and professional vibe coding

(04:53) What a professional vibe coder actually does day-to-day

(09:26) Why non-technical backgrounds can be an advantage

(12:24) The importance of self-awareness

(14:42) His “genie and three wishes” mental model

(17:43) Developing taste and judgment in the age of AI

(21:46) The parallel project approach for better outcomes

(29:30) Creating dynamic context windows with PRDs

(36:56) Why elite vibe coders focus on planning, not coding

(44:43) Creating MD files to guide AI development

(50:57) Why prototyping still matters

(56:50) Why “good enough” is no longer good enough

(01:00:53) The future of engineering in an AI world

(01:05:14) What to do when you get stuck: his 4x4 debugging workflow

(01:14:27) Helping agents learn from their mistakes

(01:15:35) Why watching agent output is more important than code

(01:19:08) The incredible pace of AI development

(01:22:55) Why emotional intelligence will become more valuable

(01:28:30) How to become a professional vibe coder

(01:30:10) Why building in public is the fastest path to opportunities

(01:37:03) Final thoughts on focusing on quality over tech stack

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Referenced:

• The new AI growth playbook for 2026: How Lovable hit $200M ARR in one year | Elena Verna (Head of Growth): https://www.lennysnewsletter.com/p/the-new-ai-growth-playbook-for-2026-elena-verna

• Elena Verna on how B2B growth is changing, product-led growth, product-led sales, why you should go freemium not trial, what features to make free, and much more: https://www.lennysnewsletter.com/p/elena-verna-on-why-every-company

• The ultimate guide to product-led sales | Elena Verna: https://www.lennysnewsletter.com/p/the-ultimate-guide-to-product-led

• 10 growth tactics that never work | Elena Verna (Amplitude, Miro, Dropbox, SurveyMonkey): https://www.lennysnewsletter.com/p/10-growth-tactics-that-never-work-elena-verna

• Lovable: https://lovable.dev

• Lovable + Shopify: https://lovable.dev/shopify

• Everyone’s an engineer now: Inside v0’s mission to create a hundred million builders | Guillermo Rauch (founder and CEO of Vercel, creators of v0 and Next.js): https://www.lennysnewsletter.com/p/everyones-an-engineer-now-guillermo-rauch

• Mobbin: https://mobbin.com

• Dribbble: https://dribbble.com

• 21st.dev: https://21st.dev

• Lovable base prompt generator: https://chatgpt.com/g/g-67e1da2c9c988191b52b61084438e8ee-lovable-base-prompt

• Lovable PRD generator: https://chatgpt.com/g/g-67e1e85fbeac8191a69b95c6d5c42ef6-lovable-prd-generator

• Felix Haas’s newsletter: https://designplusai.com

• Bauhaus: https://en.wikipedia.org/wiki/Bauhaus

• Glassmorphism: https://www.figma.com/community/plugin/1197106608665398190/glassmorphism

• UI style guide: http://uistyle.lovable.app

• Cloudflare: https://www.cloudflare.com

• Ben Tossell on X: https://x.com/bentossell

• The rise of Cursor: The $300M ARR AI tool that engineers can’t stop using | Michael Truell (co-founder and CEO): https://www.lennysnewsletter.com/p/the-rise-of-cursor-michael-truell

• Peter Thiel says AI will be ‘worse’ for math nerds than for writers: https://www.businessinsider.com/peter-thiel-ai-worse-for-math-professionals-than-writers-2024-4

• Andrej Karpathy on X: https://x.com/karpathy

• The 100-person AI lab that became Anthropic and Google’s secret weapon | Edwin Chen (Surge AI): https://www.lennysnewsletter.com/p/surge-ai-edwin-chen

• Why experts writing AI evals is creating the fastest-growing companies in history | Brendan Foody (CEO of Mercor): https://www.lennysnewsletter.com/p/experts-writing-ai-evals-brendan-foody

• Slumdog Millionaire: https://www.imdb.com/title/tt1010048

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Production and marketing by https://penname.co/. For inquiries about sponsoring the podcast, email podcast@lennyrachitsky.com.

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Lenny may be an investor in the companies discussed.