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2 posts with the tag “indiehacker”

My GPT Wrapper Makes $550 MRR One Year After Launch

Hey builders,

I wanted to share my journey building a micro-SaaS, CoverLetterGPT, which now earns $550/month in recurring revenue (MRR)—all while requiring minimal effort and maintenance. Here’s how I did it and why I believe small, simple SaaS apps are an underrated way to start as an indie maker.

Quick Stats:

  • Built in 1 week
    • using Wasp, a React, NodeJS, & Prisma framework
    • and Chakra UI for the design system.
  • Runs on autopilot
  • ~$550 MRR after one year
  • Minimal customer support—only 3 Stripe disputes to date
  • Costs ~$15/month to operate (hosting + OpenAI API fees)
  • Deployed on Railway & Netlify

BTW, I built Open SaaS, the free, open-source SaaS template based on what I learned from building and launching CoverLetterGPT.

Because Open SaaS is a community-driven project, it also benefits from community feedback and contributions, so it boasts a clean codebase and a ton of useful features. Check it out and give us a star! We’re always improving it.

⭐️ Star the Open SaaS repo and support open-source tools for builders, by builders!

Small Wins Are Worth It

Many developers think a SaaS has to be big, flashy, or wildly profitable to be worth building. I disagree. For me:

  • $550/month is fantastic as side income.
  • It runs itself, requiring virtually no maintenance.
  • I can balance it easily alongside my full-time job.
  • It’s fun and doesn’t consume my free time.
CoverLetterGPT MRR Graph

Here’s why I think you should aim for small, achievable SaaS projects instead of trying to “hit it big” from the start.

Build & Launch Fast

CoverLetterGPT Reddit Post

The most important lesson I’ve learned: speed is everything. The faster you launch, the faster you’ll know if your idea works. Here’s what worked for me:

  1. Avoid long, drawn-out failures: Build small, execute early.
  2. Use the fastest tools available: I used Wasp because it gives me all the building blocks already set up (auth, database, cron jobs, email sending), letting me focus on the business logic of the app. Paired with Chakra UI, I was able to build the app in about 1 week.
  3. Forget perfection: I didn’t worry about making it pretty or perfect—it just had to work.

Keep It Simple

The beauty of micro-SaaS is in its simplicity. Here’s why:

  • My app does one thing well: generating cover letters based on résumés and job descriptions.
  • There’s no need for a fancy landing page or marketing gimmicks. This is my 🌶 hot take.
  • Users get 3 trial credits—enough to try the app and see value before paying.
CoverLetterGPT landing page

One of the biggest perks of micro-SaaS is how low-maintenance it can be. With CoverLetterGPT, I rarely handle customer service thanks to its simplicity.

This means I spend my time on new ideas rather than maintaining old ones.

It’s All About Tradeoffs

While I could optimize and grow CoverLetterGPT further, I’ve chosen to keep it small and simple. For me:

  • Small wins are still wins.
  • I value having a side project that’s easy to manage alongside my full-time job.
  • I’d rather have less stress than chase higher profits.

If you’re thinking about launching your own SaaS, here are some helpful resources:

Final Thoughts

If you’re considering building a SaaS, don’t overthink it. Start small, move fast, and treat it as an experiment. Forget the “rules” and focus on launching. Here’s what matters most:

  • Keep it simple: Build an app that solves one problem well.
  • Launch fast: Test your idea and iterate based on real feedback.
  • Minimize effort: Aim for maximum reward with minimal maintenance.

For me, $550 MRR isn’t just “enough”—it’s amazing. It’s proof that small, focused apps can succeed, and they’re a great way to build confidence and skills as a maker.

Let’s stay in touch!

If you found this helpful, check me out on Twitter where I like to build in public and share what I’m learning and building.


⭐️ Star the Open SaaS repo and support tools that help you build fast!

How I Built & Grew CoverLetterGPT to 5,000 Users and $200 MRR

Hey, I’m Vince…

Vince Headshot

I’m a self-taught developer that changed careers during the Covid Pandemic. I did it because I wanted a better career, enjoyed programming, and at the same time, had a keen interest in IndieHacking.

If you’re not aware, IndieHacking is the movement of developers who build potentially profitable side-projects in their spare time. And there are some very successful examples of IndieHackers and “solopreneurs” out there inspiring others, such as levels.io and Marc Lou.

This thought of being able to build my own side-project that could generate profit while I slept was always attractive to me.

CoverLetterGPT

So I’m happy to report that I’ve finally done it with my first software-as-a-service (SaaS) app, CoverLetterGPT.xyz, which I launched in March 2023!

I’ll be the first to admit that the results aren’t spectacular, but they’re still something I’m very proud of:

  • over 5,000 registered users
  • $203 monthly recurring revenue (MRR)

Below, I’m going to share with you how I built it (yes, it’s open-source), how I marketed and monetized it, along with a bunch of helpful resources to help you build your own profitable side-project.

What the heck is CoverLetterGPT?

CoverLetterGPT.xyz was an idea I got after the OpenAI API was released. It’s an app that allows you to upload a PDF of your CV/resumé, along with the job description you’re applying to, and it will generate and edit unique cover letters for you based on this information.

It also lets you save and manage your cover letters per each job, making it easy to make and apply to multiple jobs without having to keep copy and pasting all your important info into ChatGPT!

What’s the Tech Stack?

Tech Stack

CoverLetterGPT is entirely open-source, so you can check out the code, fork it, learn from it, make your own, submit a PR (I’d love you forever if you did 🙂)… whatever!

I built it using the Wasp full-stack framework which allowed me to ship it about 10x faster.

Why?

Because Wasp as a framework allows you to describe your app’s core features in a main.wasp config file. Then it continually compiles and “glues” these features into a React-ExpressJS-Prisma full-stack app for you.

All you have to focus on is writing the client and server-side logic, and Wasp will do the boring stuff for you, like authentication & authorization, server config, email sending, and cron jobs.

BTW, Wasp is open-source and free and you can help the project out a ton by starring the repo on GitHub: https://www.github.com/wasp-lang/wasp 🙏

star wasp

⭐️ Star Wasp on GitHub 🙏

For the UI, I used Chakra UI, as I always do. I like that it’s a component-based UI library. This helps me build UI’s a lot faster than I would with Tailwind or vanilla CSS.

For payments, I used Stripe, (I’ll go into the details of monetization below).

The Server and Postgres Database are hosted on https://railway.app, with the client on Netlify.com’s free tier.

By the way, If you’re interested in building your own SaaS with almost the same stack as above, I also built a free SaaS template you can use that will save you days of work!

How I Marketed It

My biggest take-away from this whole project was that open-sourcing it was the best way to market it!

This seems counter-intuitive, right? Why would making the code available for anyone to see and copy be good for a business? You’re basically rolling out a red carpet for competitors, aren’t you?

Well, not quite.

First of all, the number of people who will realistically spend the time and energy launching a direct competitor is low. Also, most people interested in your open-source code want to learn some aspect of it and apply it to their own ideas, not just copy yours directly.

Secondly, and most importantly, the fact that it’s open-source makes people a lot more receptive to you talking about it.

reddit

When you present something you’ve built and give people the opportunity to learn from it, they’re much more welcoming! As a result, they’re more likely to upvote it, share it, use it, and recommend it to others.

This is exactly what happened with CoverLetterGPT! As a result of me sharing the open-source code, it get featured on the IndieHackers.com newsletter (>100k subscribers), shared on blogs, and talked about on social media platforms.

product hunt

And even though it’s a small, simple product, I tried launching it on Product Hunt, where it also performed considerably well.

So, all together, these initial efforts combined gave my product a good initial marketing presence. To this day, I haven’t really done much else to market it, except some twitter posts (and this post, if you want to consider it marketing 🤑).

How I Monetized It

When I first launched in March 2023, I didn’t really expect anyone to pay for the product, but I wanted to learn how to use Stripe as a payments processor, thinking that the skills might be useful in the future.

So I started simple, and just put a one-time payment link for tips. No paywall, no subscriptions. It was entirely free to use with any tip amount welcome.

To my surprise, tips started coming in, with some as high as $10 dollars!

This encouraged me to force users to login to use the product, and add a paywall after users used up 3 credits.

My initial payment options were:

  • $4.95 for a 3 months access
  • $2.95 for 10 cover letter generations
pricing page

That went reasonably well until I implemented the ability for users to use GPT to make finer edits to their generated cover letters. That’s when I changed my pricing and that’s when better profits started to come in:

  • $5.95 / month subscription with GPT-4
  • $2.95 / month subscription with GPT-3.5-turbo

Currently, over 90% of my customers choose the more powerful, more expensive plan with GPT-4, even though the 3 trial credits use the GPT-3.5-turbo model.

(I also integrated Bitcoin Lightning payments — check out the repo if you want to learn how — but haven’t received any yet.)

Now, with an MRR of ~$203, my monthly profit of course depends on my costs, which are:

  • Domain Name: $10/year
  • OpenAI bill: ~ $15/month
  • Hosting bill: ~ $3/month

Which leaves me at about ~ $183/month in profits 😀

Future Plans

One of the most surprising aspects about CoverLetterGPT.xyz’s success is that, on the surface, the product is very simple. Also, I’ve done very little in the way of SEO marketing, and haven’t continued to market it much at all. The current growth is mostly organic at this point thanks to my initial marketing efforts.

But I still have some plans to make it better:

  • buy a better top-level domain (TLD), like CoverLetterGPT.ai
  • add more features, like the ability to generate interview questions based on the cover letters
  • improve the UX and make it look more “professional”

If you have any other ideas how I could improve it, drop me a comment, message me on twitter/x, or submit a PR to the repo.

Final Words + More Resources

My intention with this article was to help others who might be considering launching their own SaaS product. So I hope that’s been the case here. If you still have any questions, don’t hesitate to ask.

Here are also the most important links from this article along with some further resources that will help in building and marketing your own profitable side-project:

Oh, and if you found these resources useful, don’t forget to support Wasp by starring the repo on GitHub!

star wasp

⭐️ Thanks For Your Support 🙏