Sergio Pereira (@sergiorocks) 's Twitter Profile
Sergio Pereira

@sergiorocks

CTO building tech products, startup teams & writing about it.

Building jobscopilot.ai

I work as a Fractional CTO for tech startups. DMs open

ID: 2539056306

linkhttps://www.remote-work.io/newsletter/ calendar_today01-06-2014 08:14:16

9,9K Tweet

43,43K Followers

1,1K Following

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As a Fractional CTO, I'm increasingly getting hired by Founders right at the foundation stage of their startup. This means they want to have me around before: - They hire their first Software Engineers, - Any code is written, - Even before tech stack or tooling is chosen. These

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The most challenging part of a Startup CTO job is to know when to shift gears. - Gear 1 -> Scrappy, MVP stage. Speed > Quality - Gear 2 -> Traction, get ready for scale. Quality > Speed Product-Market-Fit is the ultimate metric to decide when to shift gears. Gear 1: Before

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Investors don’t just fund vision. They fund the team that can pull it off. A polished no-code MVP can turn heads. It shows initiative. Hustle. Momentum. But when the investor meetings turn serious, they’ll start asking tough questions: - Who’s leading the tech? - Can this

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Your colleague opens a PR. You're the reviewer. How can you tell that most code changes were written by Cursor/Copilot/etc? What's the one thing that instantly gives it away?

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“We paid $50k and still don’t have a working product” - a Startup Founder told me. Too many first-time founders have this same story: - You hire an agency. - You explain your idea. - They nod, build something, invoice you for it. But 3 months later, your product still doesn’t

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Polished comments are the most obvious hint for AI-generated code. Indeed. But beyond that, how can you tell it's AI-generated by looking into the code itself? I start: Over-modularized code, with functions doing silly little things like changing a variable's value.

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The em dash is one of the best hints for AI-generated content. In code comments and anywhere else. Even if you prompt an LLM to never use the em dash, it will write it anyway. I wonder why, since very few humans ever write with em dashes.

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AI tools are turning junior devs into solo builders. That’s exciting, but risky. With tools like Lovable and Cursor, it’s never been easier to ship an MVP. You can scaffold an app, write an auth flow, and deploy in hours. No senior dev. No architect. No reviews. Just prompts.

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After 10 years as a Startup CTO, one thing is crystal clear. There are multiple ways to be successful, and no one-size fits all. I've worked with Founders making millions in ARR with a typeform and a spreadsheet. It's key to be nimble at launch, and fast to scale after getting

After 10 years as a Startup CTO, one thing is crystal clear. There are multiple ways to be successful, and no one-size fits all.

I've worked with Founders making millions in ARR with a typeform and a spreadsheet.

It's key to be nimble at launch, and fast to scale after getting
Sergio Pereira (@sergiorocks) 's Twitter Profile Photo

“I hired a dev agency to build my MVP. They looked great in meetings, but turns out they are terrible at building” - It's the origin story of several clients of mine over the years. Every founder has met that agency: - Slick decks - Constant smiles - Promises of “next sprint”

Sergio Pereira (@sergiorocks) 's Twitter Profile Photo

Startup Founders confuse speed with progress. They’re not the same. Yes, you launched in a weekend. You hacked together a no-code MVP, spun up a landing page, maybe even got a few signups. That’s great hustle. But here’s the real question: What did you learn? Too many founders

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Many startups struggle to onboard new SW Engineers, no one understands the code. They wanted a simple MVP. Some software development agency delivered it. But now they’re trying to scale, and every new dev they talk to tell them: - “This code is a mess” - “It’s impossible to

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“I didn’t know how to code, so I built my MVP using Google Sheets. I validated the idea, got paying customers, then hired developers to scale it.” - This Founder on reddit wrote They now run a SaaS with over $700k in ARR. And this is what startup reality looks like in 2025. You

“I didn’t know how to code, so I built my MVP using Google Sheets. I validated the idea, got paying customers, then hired developers to scale it.” - This Founder on reddit wrote

They now run a SaaS with over $700k in ARR. And this is what startup reality looks like in 2025.

You
Sergio Pereira (@sergiorocks) 's Twitter Profile Photo

Hiring a dev agency to build your MVP? Read this first. I’ve worked with dozens of non-technical founders. You’d be surprised how often I hear the same story: - “We hired a software development agency. Six months later, we’re over budget, behind schedule, and stuck.” Most

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This is what vibe coding at scale looks like. An MVP built by Cursor, this dev simply hit the tab key a bunch of times. Launched. Gained traction. Then
 chaos. - API keys maxed out - People bypassing the paywall - Junk flooding the database - Founder blindsided, overwhelmed,

This is what vibe coding at scale looks like.

An MVP built by Cursor, this dev simply hit the tab key a bunch of times. Launched. Gained traction. Then
 chaos.

- API keys maxed out
- People bypassing the paywall
- Junk flooding the database
- Founder blindsided, overwhelmed,
Sergio Pereira (@sergiorocks) 's Twitter Profile Photo

If your engineering budget is tight, you’re probably hiring in the wrong zip code. Early-stage startup budgets don’t stretch far. But talent doesn’t need to be local to be world-class. Look at the data: - Median dev salary in the US? ~$150k. - Portugal? $36k. - Argentina? $21k.

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The dev agency says everything’s “on track”. But you have no idea what’s actually been done. Sounds familiar? This is one of the most common pain points I hear from non-technical Startup Founders: - You’re paying for a product, but you feel completely out of the loop. - You ask

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Let’s be honest: Scope creep is real, but so is rigid thinking. I hear this all the time from early-stage founders: - “We wanted to tweak one feature after user feedback, and suddenly the agency said we owed more money.” - “They were only focused on ‘what we signed’, not what