Welcome to Build to Launch Fridays, where we meet the builders turning domain expertise into AI-powered products.
Every Friday, I'm spotlighting someone from the vibe coding builders collection who's doing exactly what I believe is the future: using AI not as just another tool, but as a true collaborator to transform curiosity, passion, and years of professional knowledge into something scalable and ownable. No VC funding, no technical co-founders, no permission required, just domain experts who decided to build.
Today, meet Finn Tropy — the creator of the most popular Substack product — deeply technical, yet fully in tune with the vibe coding spirit.
Have you ever met someone who makes building look effortless? Someone who cranks out products that just work, quietly accumulating users and revenue while others struggle with their first MVP?
When I first encountered Finn online, he struck me as one of those technical wizards who could dissect your digital footprint with a few keystrokes. But after getting to know him, I realized something more interesting: he's not just technically skilled, he's a domain expert who learned to build because he understood creator pain points better than anyone else.
Finn is the creator of Substack's most popular publishing tools, and his story perfectly embodies what I believe about domain expertise meets AI collaboration.
When I proposed he join Vibe Coding Builders, he was genuinely puzzled at first. But as we talked about the bigger idea, that everyone is building in isolation, and we need experienced builders willing to guide newcomers, it aligned perfectly with his philosophy of builder abundance. Plus, he'd already embraced Cursor and AI assistance in his workflow, making his perspective even more valuable to our community.
Following the questions below, you'll see exactly why I had that initial impression, and how he embodies the perfect vibe builder spirit.
Origins & Early Products
I first heard about your Substack Notes Scheduler earlier this year, was that the very first product you built around Substack?
I’ve done some web development before, but never written any Chrome extensions. Initially, I copied and pasted the JavaScript code on the Substack post before I started using Gumroad to upload the extensions.
Now this sounds familiar! When I first started writing on Medium I encountered products like Medium engagement metrics and top authors. Now I found who is the creator behind it!
I hadn’t heard of the free Substack Stats Exporter it before. Was it intentionally not promoted much?
My 9-to-5 job consumed most of my energy until August, leaving me with, on average, about 4 hours per week for writing and building. My focus has been on solving problems and building products, and less on promotional activities.
Four hours per week? That was incredible productivity for creating so many different applications.
How many other products have you built since then?
After I published Substack Stats Exporter, I got some traction and was actively following discussion threads.
I found one where people were discussing missing Substack features, and many identified Note scheduling as a significant issue.
Based on the survey results, I began building the Substack Dashboard, a more ambitious project. I built a powerful analytics dashboard that tracked 13,844 newsletters, 2.3 million posts, and 1.3 million Notes, providing deep insights into engagement trends and growth patterns across Substack.
With a stressful 9-to-5 job, I had only a few hours over the weekends to focus on this, but I managed to build a high-performance data pipeline to keep the data fresh, a backend service running multiple services in Docker containers, including a PostgreSQL database, a Grafana instance for visualization, an NGINX proxy for traffic management, etc.
By early March, I recognized that the project was much more complicated than I had anticipated. By April 5th, I launched the service with high expectations. I had 20 people to sign up, but soon realized that I was not meeting their expectations. All but one customer cancelled subscriptions. I learned many valuable lessons for the projects that followed.
In early June, I started from scratch, built and launched the Substack Control Center, which addressed the shortcomings of the Substack Dashboard. The customer feedback has been overwhelmingly positive, and I currently have 43 customers using it.
Starting from mid-June, I began building the Substack Pro Studio and conducted extensive beta testing with 23 beta testers worldwide.
That’s a hell of a lot of building experience packed into just half a year! And already we can see the patterns:
he built a simple product to solve his own problem,
tuned it into an alert system for Substack,
spotted the biggest issue and fixed it fast,
then followed up with how-to guides, surveys, and iterations.
He didn’t stop there, his curiosity drove him to expand into a monster project (which he admits missed the mark), then pivoted to even better products, and finally landed with Substack Pro Studio for another huge outcome (more about that soon!!!).
And let’s not forget, spinning up Docker containers, maintaining a PostgreSQL DB, juggling Nginx proxies… anyone who’s done it knows how painful that is. Massive respect for putting in that effort without complaining. Honestly, even the “failed” product he calls it? The dashboard is gorgeous.
Product Portfolio & Effort
From Gumroad, I see you have six products. Which one did you spend the most time building, and roughly how long did it take?
The Substack Pro Studio has taken the longest time. I started working on it in mid-June and planned to launch on August 29th. This product is a comprehensive application designed for serious Substack creators who want to grow their newsletters and engage their audience. I’ve incorporated all the lessons I’ve learned during the last 12 months. Feedback from 23 beta testers has been overwhelmingly positive.
I asked Finn about Substack Pro Studio before launch, and he said the feedback was “overwhelmingly positive.” I wondered in myself, “how positive does THAT mean?” A few days later, I saw the results, and yes… it was truly OVERWHELMING.
I was trying out the Substack Pro Studio way earlier than this build to launch series, and was genuinely learning how my notes should be improved to reach the best results.
Your first two days of Substack Pro Studio was huge, and brought in 100+ users! What drove that adoption, and what do you think was your best move?
I've been sharing my progress with Substack Pro Studio for the last two months, posting screenshots, fixing issues that beta testers were sharing and also their wins.
I had 23 beta testers I had worked with, fixing all the problems they bumped into, like Substack custom domains and their DNS configuration issues. I added features they requested, and some new ones like theme based drip scheduling and Engagement Heatmaps with time slot optimizer. I worked on optimizing the three built-in AI Assistant prompts based on what I learned from another project where I tested AI self-learning loops.
I did create a structured growth experiment to share the exact steps I took to generate 24% month-over-month new subscriber growth, and I have several beta users trying to replicate the growth patterns. I worked with "Old Man Talks" to create a customer testimonial on his growth results for the last 3 weeks.
Also, I created a collaboration product with Yana G.Y., where we both brought our products into one bundled and integrated product - Substack Pro Studio and CreativeTech Notes Writer v3 GPT (finntropy.gumroad.com/l/creativetech_substack_pro_studio ) that Yana is offering as part of her Unplugged newsletter subscription to her existing 5100+ subscribers.
Some other things that might have helped was a complete User Guide with several tutorial videos how to get started and some best practices how to get most out of this tool. All this was a lot of work to get done before the launch day. Finally, I made a great upgrade offer to existing Notes Scheduler customers to motivate them to upgrade.
A lot of this work might seem invisible but I think it created enough momentum to get people moving.
Finn is so generous in sharing every step, in such detail, of how he actually achieved this result. But even with the roadmap laid out, it’s still Finn who will carry it through, because he’s the real builder.
It’s not the map, it’s the action: taking the steps, paying attention, diving into the details. Reading this is a wake-up call for me about the products I’ve built, abandoned, and never followed up on.
Did you get crazy busy right after the launch day?
I have a Gumroad mobile app on my phone that makes this cash register sound whenever somebody makes a purchase. The emails were scheduled to go out at 8 AM ET on Friday, so I went out for a morning walk with my dog. It was almost funny when my phone started making cash register sounds as we were walking. I normally get like 4 per day, but in those first 30 minutes or so my phone kept ringing 12 times, so I knew that something special was going on. And yes, I have been busy helping people after the launch.
Ohhhh keep hearing cash register sounds? That must be the best music ever 😍
Which product has generated the most revenue so far, and how much time did it take to build that one?
The Substack Scheduled Notes product has generated approximately $ 10,000 in revenue so far. Although the initial v1.0 product took me just a few hours to build over the Thanksgiving holiday, I have written and shipped over 40 releases and bug fixes since then, addressing issues and feature requests from nearly 500 active users.
Yeah, it’s this spirit of living up to your job and really drilling down into the product, that we can never emphasize enough.
You mentioned there’s traffic from Perplexity, that's wild. Could you share a bit more detail? Especially, what did you do right to get in the radar of Perplexity?
I have some Gumroad traffic from perplexity.ai but the interesting detail was that the conversion rate was 50%. Normally my conversion rate is between 4% - 17.2% from other sources. perplexity.ai has this unusually high conversion rate that peaked my interest. I'm not using this service so I don't know how they found my Gumroad store and why 50% people are buying when other traffic sources have only 4% buying. This is a great mystery to me.
It’s a great mystery, and a huge curiosity for me too. This once again suggests that traditional SEO and existing high domain sites are still great for AI discoverability.
Since we are talking AI, when building or distributing these products, did AI help you in any way?
I've used AI in building Substack control center and pro studio, others are hand coded. Also, I've used AI in multiple analytics jobs, some of which became articles.
It’s rare to see someone so deeply technical readily embrace AI and openly credit it.
Strategy & Market
What has been your go-to-market strategy? Was it mostly driven by Kristina’s early support and sharing?
I didn’t really have a go-to-market strategy before Dec 2024. Kristina God reached out to me on December 20th, and over the Christmas holidays, we hashed out a plan to create a demo video for Kristina’s YouTube channel. She posted the video on January 12th, and it generated my first $200 per day in sales on Gumroad on January 13th. She really helped to increase visibility, and her subscribers received a special deal that drove a significant number of sales.
Yup, Kristina is so warm-hearted. She mentioned this to me multiple times.
How did you discover the business of creating extensions? Was it something you were experimenting with long before Substack took off?
After writing on Medium for 18 months, I did a retrospective to figure out what was working and what didn’t resonate with my readers. You can read it from here: The Investor’s Playbook for Writers.
I decided to focus on a few things:
Listen for reader feedback and build a better understanding of my audience.
Provide practical tools and guides to my readers.
Help to solve problems and document the steps taken
Work on my Finn’s Newsletter for another channel to distribute my stories.
Add more products like The Top Authors Dashboard on Gumroad
This was a truly pivotal moment for me, and it changed the trajectory of my newsletter. I started with 24 subscribers, and a year later, I now have 953. I wrote an article about this transformation: How I Turned My Substack Posts into Dividend-Paying Assets.
You’ve got competitors now, how do you feel about that? Would you consider changing your strategy in response?
It is great to have more developers in this space - that is a good sign that there is a market for the tools we are providing. I am not changing my strategy and will continue down the path I have taken over the last 12 months.
Talking to Finn, you get the sense he welcomes challenges, not to win the game, but to create a sense of abundance in his own world. With that mindset, it’s hard to be ever truly losing.
Operations & Challenges
From all your users, what would you say the satisfaction rate is?
I have not measured customer satisfaction using any industry standard method like NPS score so far. On Gumroad, the Substack Scheduled Notes have 18 5-star reviews. The Substack Control Center has 4 5-star reviews. The Substack Stats Exporter has 9 5-star reviews. I have not yet requested product reviews, so these ratings are provided by existing customers spontaneously.
When everything is voluntarily happening, that’s a huge impact!
Do you have any infrastructure or hosting costs for these tools?
All products, except the Substack Dashboard, are Chrome extensions that have zero hosting costs. I’m trying to keep the costs low and pass the savings to customers.
Have you ever been mistaken for someone else or misattributed for your work? If so, how did you handle that?
Yes, I wrote an article Welcome to the Plagiarism Party and had this Notes thread with the person who copied my Gumroad Product Description and User Guide. He did not realize that people who buy a Notes Scheduler will use Google and find me as the support contact.
I have had several cases where I receive an email from a person requesting help, and after a few emails and screenshots, it becomes clear that they have purchased another product - not mine. I’m trying to help people, but I'm unable to support other developers’ products.
That’s tough. In some ways, the more you become known, the more problems you’ll encounter.
Relationships & Community
You come across as a very kind person, do most users who talk to you end up becoming friends? Do they also become returning customers or free referrers?
I do have a lot of returning customers who buy all my products, and I’m chatting with them frequently.
Do you offer any affiliate programs?
I currently have 12 affiliates and am open to adding more.
Great! I’m sooo in!!! I quickly applied for the affiliate links and they are now available:
This is my very first public affiliate, so excited to see if it leads to anything!
Current & Future Focus
I asked him a bunch of now redundant/silly questions about the future focus, so I won’t bore you with those. In short: “Substack Pro Studio” will be the focus going forward — it’s the next-gen Notes Scheduler.
Looking back, what’s the most regretful thing you’ve done, and something you would never do again?
The Substack Dashboard project was a mistake. I burned my weekends from February to April, building a fairly complicated system that didn’t meet customers' expectations. I had a clear product vision that was misaligned with what customers really wanted, and this is not the first time I have made such a mistake. The good news is that I learned a great deal and can reuse some of the components in future projects. However, I cannot say that I would never make this mistake again, given my history. It is important to engage with customers early and get beta feedback well before any launch plans.
I’ve learned the similar lessons: you stumble through mistakes and failures all the time, but each one teaches you something new, and that becomes the secret sauce for the next little success.
Final Words
We talk a lot about AI superpower, about leveraging technology to 10x yourself. But Finn's story reminds us of something deeper. Yes, AI can amplify your capabilities dramatically, but the real drive, the core builder spirit, still lives within you.
It's that unstoppable curiosity, that eagerness to explore, that patience to deal with bug reports and customer feedback, tweaking every detail until it actually works and meets every user's expectation. That's what moves the needle. When AI comes in, it frees you to focus your full energy on what you care about most:
The exploration, the product building, the customer relationships.
What strikes me about Finn is how naturally he embraces both sides: deep technical expertise AND AI collaboration. No ego, no resistance, just practical building. He represents what I'm seeing more and more in our vibe coding builders community: people who understand that the future belongs to those who combine their hard-earned domain knowledge with AI assistance, whether they're seasoned developers or domain experts learning to code.
That's exactly the spirit we're building around.
If you’re turning your expertise into products, building with AI, or helping others do the same, you belong here. Join the vibe coding builders community and get featured on Build to Launch Friday. Curious why it all started? Here’s the full story behindVibe Coding Builders.
If Finn’s insights inspire you, connect with him, he's the kind of friend you’ll never regret knowing.
Thanks Jenny and Finn for this amazing story. Really inspirational for those of us who are trying to build something with similar depth and meaning. 🙏
Love how Finn shows that consistent small steps with focus can outpace “big launch” hype. True builder energy.