Handle
@alexcooldev
Followers
10K-50K
Focus Area
Indie Hacking / SaaS
Alex Nguyen is a 25-year-old Vietnamese software engineer turned successful indie hacker who transformed his career from a traditional 9-to-5 developer into a thriving solopreneur earning over $40,000 monthly. Based in Ho Chi Minh City, Vietnam, Alex embodies the modern independent developer dream—building profitable SaaS products while learning in public and sharing every step of his journey with radical transparency.
Unlike many developers who keep their metrics private, Alex openly shares his revenue breakdowns, user counts, and operational costs. His monthly income reports reveal earnings from multiple streams including Feynman AI (formerly NoteWave), OrgaTok, X promotions, and consulting services. This transparency has made him a trusted voice in the indie maker community, inspiring thousands of aspiring developer entrepreneurs worldwide.
Alex's path wasn't a straight line to success. His story includes:
This startup journey resonates deeply with developers because it shows both the struggles and triumphs of building in public.
Feynman AI (originally launched as NoteWave AI) is an AI-powered study note tool that helps students and professionals create notes, mind maps, quizzes, and flashcards from audio, PDFs, and other content. The tool leverages the Feynman technique—a learning method that emphasizes understanding through teaching—to help users achieve deeper comprehension.
The numbers speak for themselves:
| Metric | Achievement |
|---|---|
| Monthly Users | 310,000+ |
| Daily Active Users | 8,000-12,000 |
| Monthly Revenue | $19,700-$21,400 |
| Total Revenue | $130,000+ |
| Development Time | 11 months of consistent work |
Alex built Feynman AI using modern, developer productivity tools:
His choice of Next.js and TypeScript throughout the stack demonstrates his commitment to type-safe development and modern web standards.
Alex attributes his success to a disciplined daily schedule maintained for 11 consecutive months:
This balanced approach challenges the stereotype of developers who only code. Alex proves that growth marketing skills are equally important for indie hackers seeking sustainable income.
While most SaaS founders focus on traditional channels like Product Hunt or Reddit, Alex discovered that TikTok marketing could drive exponential growth for developer tools. He grew Feynman AI to $20,000/month in just seven months primarily through organic TikTok content—no paid ads required.
His TikTok approach focuses on:
Learn more about social media growth strategies from successful developers on X (formerly Twitter) who share similar insights.
Beyond Feynman AI, Alex built OrgaTok.co—a tool teaching organic marketing strategies. This product generates an additional $2,500-$8,000 monthly, demonstrating his ability to identify market needs and execute quickly. The meta-irony isn't lost: Alex teaches organic marketing using the very strategies that made his own products successful.
Alex's journey from $0 to $40K wasn't about building the perfect product—it was about consistent action. He shipped features, gathered feedback, and iterated rapidly using tools like Cursor and Claude Code to accelerate development.
Spending equal time on marketing and coding challenges the developer mindset that "good products sell themselves." Alex proves that product development and growth marketing are twin engines of success.
When his first attempt at indie hacking failed in mid-2024, Alex didn't see returning to a job as defeat—he saw it as strategic regrouping. This pragmatic approach kept him financially stable while building his products on the side.
By sharing his revenue, tech stack, operational costs, and decision-making process, Alex built an audience of 38,900+ X (Twitter) followers. This audience became customers, supporters, and collaborators—proving that transparency is a competitive advantage.
Alex intentionally rebranded from "NoteWave AI" to "Feynman AI" because the new name better communicated the product's value proposition. The Feynman technique is widely recognized in education circles, making the product easier to discover and share virally.
Here's the complete operational cost breakdown Alex shared publicly:
Total operational cost: ~$765/month to serve 310,000 users and generate $21,400/month—an impressive 28x return on infrastructure investment.
Alex shares his journey as it happens—revenue updates, product launches, marketing experiments, technical decisions, and personal reflections. Following him means getting an MBA in indie hacking delivered through tweets.
As a full-stack developer with six years of experience, Alex shares code snippets, tech stack decisions, and developer productivity tips. His posts about using Windsurf, Lovable, and Bolt.new provide valuable insights into AI-assisted development.
Alex doesn't just share wins—he posts about struggles, failed experiments, and tough decisions. This authenticity makes his success story believable and replicable for aspiring solopreneurs.
Alex actively engages with other indie hackers, offers advice through 1:1 consultations ($1,000/month income stream), and celebrates others' wins. He exemplifies the collaborative spirit of the maker community.
Alex publicly states his mission: building from $0 to $1M ARR (Annual Recurring Revenue) while documenting every step. His focus on AI + Systems + Growth positions him at the intersection of three massive trends reshaping software development.
Whether you're an aspiring indie hacker, experienced full-stack developer, or startup founder looking for inspiration, Alex's X profile offers invaluable insights into building profitable products independently.
His story proves that with the right combination of technical skills (leveraging modern tools and frameworks), growth marketing expertise, and unwavering persistence, developers can break free from traditional employment and build sustainable businesses.
Follow Alex to learn:
Alex Nguyen represents the new generation of developer entrepreneurs who don't just build products—they build businesses, audiences, and sustainable lifestyles around their code. His journey from struggling developer to $40K/month founder is still unfolding, and following along means you're getting a front-row seat to one of the most authentic indie hacker success stories of 2025.
Alex Nguyen is a 25-year-old Vietnamese software engineer and indie hacker who built Feynman AI (formerly NoteWave), an AI study tool that generates over $40,000/month with 310,000+ users. He shares his transparent journey from $0 to building multiple profitable SaaS products.
Alex posts about indie hacking, SaaS development, revenue transparency, organic marketing strategies (especially TikTok), tech stack decisions using Next.js and TypeScript, and his daily routine of coding 4 hours and marketing 4 hours. He shares real-time updates about building Feynman AI and OrgaTok.
Developers should follow Alex to learn how to build and market SaaS products independently, understand organic growth strategies that don't require big budgets, see transparent revenue breakdowns, and get inspired by an authentic indie hacker journey that includes both failures and successes.
Feynman AI is an AI-powered study tool that creates notes, mind maps, quizzes, and flashcards from audio and PDFs using the Feynman learning technique. Alex built it using Next.js, React Native, NestJS, Supabase, and TypeScript, growing it to 310,000+ users primarily through organic TikTok marketing.
Alex grew Feynman AI to $40K/month by working 4 hours daily on coding and 4 hours on marketing for 11 months straight. He used organic TikTok marketing, transparent revenue sharing to build trust, learning in public to grow his audience, and rapid iteration using AI development tools like Cursor.
Alex uses Next.js, TailwindCSS, Shadcn UI, React Query, and Zustand for frontend; React Native (Expo) for mobile; NestJS for backend; Supabase for database; and Cursor AI for development. His entire stack uses TypeScript for type safety, costing only $765/month in operations.
Yes, Alex's journey is very realistic because he shares both struggles and wins. He quit his job in April 2024 with $0, had to return to employment in August 2024 after struggling, then gradually grew his revenue while working a job before quitting again in March 2025 at $17,500/month. This shows the real ups and downs of indie hacking.
Alex teaches that marketing is equally important as coding for indie hackers. He demonstrates organic TikTok growth strategies, the power of learning in public, transparent revenue sharing to build trust, effective product naming for viral potential, and how to create content that educates while promoting your product.
Follow David Park (@Davidjpark96), founder of Jenni AI (5M valuation, 10M users). Learn startup growth tactics, AI product development, and authentic entrepreneurship lessons.
Follow @IndieHackers for bootstrapped startup insights, profitable side project strategies, and indie maker community inspiration. Join developers building sustainable online businesses without VC.
Marc Lou is a French indie hacker who built ShipFast, a NextJS boilerplate earning $130K+/month. Follow for build in public insights, SaaS development tips, and solo founder strategies.