Building and Launching an Invoice Payment System

Hello! What's your background, and what are you working on?

My name is Thomas Howell, and I'm the founder of two companies, Forum Education and Felix, both based in NYC. I am also, and not incidentally, a 2008 US college graduate with a degree in Comparative Literature: in other words, I entered the worst job market of the past 3 or 4 decades with no obviously-marketable skills.

Long story short, I freelanced and bootstrapped, and ultimately chose the entrepreneurship route over medicine. (I was accepted to medical school when my first company was about 6 months old.) And now I run two companies. The second company, Felix, is a venture to scale a payments system built for the first company. On the flip side, Felix is funded by the first company's revenue, and it's just starting on the road toward profitability.

So what does Felix do? It's the first autopay service for freelancers/independent professionals. You know how Uber drivers just accept requests, drive, and get paid? And passengers… do nothing, and pay? It's like that. For everyone.

Professionals log each work session, and that's it; Felix will compile their invoices, send their invoices, charge their invoices, and deposit their payments. Every week, like payroll. This saves time, effort, and anxiety for the pro while giving convenience to the client, who signs up just once and doesn't have to do anything else (though clients can easily stop payments if they wish).

Figure out the core benefit of your product vs. the existing offerings and reduce until that is the only essence.


We use it ourselves in both the professional and the client side of transactions, and we think it sets a new standard for payments services while putting payments where they belong: in the background of working relationships. More to the point, we are super excited to share it and our story with the Indie Hackers community, and to know your thoughts.

What motivated you to get started with Felix?

The short version of Felix's history is that my co-founder and I built a version of this system — actually less advanced — for our first company, a tutoring agency in New York City. We already hated invoicing, and collecting payments was a chore, so we weren't about to handle it all in the old-fashioned way for a growing team of tutors.

Instead, we invested in building an online payment system that could generate invoices, deliver them, charge them, and pay our tutors — basically run the entire business side of the company. And it's been a huge success: we've grown approximately 9x in under 3 years, cracked 7 figure annual revenue, and delivered 2,100 invoices (and counting) with 100% collection rate — and we have no staff.

So Felix is our way of helping the growing number of freelancers/self-employed professionals — the 1 person shops — jumpstart their businesses with the same upgrade.

What went into building the initial product?

A confession here: we haven't really been a lean, MVP-focused startup, despite our intentions. We have been working on Felix officially since July of 2015, and really a bit longer than that. The first inspiration dates to October 2014.

Why so long? Because we spent a year building a bad product. I was the one designing the product — and I was a total newbie. On top of that, we hired a friend with little experience doing digital to conceive and implement the brand. So those were two bad mistakes that compounded basically for a year, each hiding the other.

Face the facts early — and always.


We didn't realize that we were on a bad path until we really went to market, and then we realized: this brand is weak and the product is too complicated. Then we had a wake-up call, in part due to some candid feedback with a brand consultant, that triggered a rewrite from the ground up.

The result is a much simpler product and service. While we might have had a smoother, faster, or cheaper path to the current iteration, the fact is that it takes time and thought to get to simplicity. This "Felix 2.0" is our true initial offering.

How have you attracted users and grown Felix?

We're still finding out the best channels for our marketing, as well as the best purpose for each channel. But below are some takeaways that help to summarize our experience.

Here's what has clearly worked: in terms of downloads of our app, Apple's App Store search ads are the winner. For certain key words, we have conversions rates north of 35%, with costs per tap less than $3. The substantial majority of our downloads originate in the App Store's search ads.

Here's what didn't really work: an article in Fast Company. Don't get me wrong, it was great to our service mentioned in any magazine, much less a pretty big one like Fast Company, and much less for Felix to be the exclusive focus of the article. However, the article (which came out on a Friday evening, to be fair), generated only about 30 visits to our home page, and with a bounce rate of over 70%. So the impact was minimal.

And something else that didn't really work: a newsletter. But that said, this is definitely not something we regret trying. In the process of churning out content every week for 3 months, we made a lot of stuff that we can reuse, for example, in drip email campaigns to new users or by sharing it via social media. As one media exec told us, "Every piece of content has nine lives."

What's your business model?

Felix's business model is a simple commission: 1% of the transacted volume. This way, our incentives are aligned with our users': we don't get paid unless they get paid (and getting paid is important to us; our slogan is: "Log hours. Get paid Friday.").

We're based on Stripe, which offers a number of advantages. But the interesting part for us is that we were actually one of the first groups to use the Stripe Connect platform in 2014 (for our first company). We are super familiar with it, and Felix is very possibly the most in-depth implementation of Stripe Connect in existence today.

We are not profitable yet — nor particularly close. That said, our relaunch is underway now, and we run a lean operation. And as much as we believe in reinvesting profits — which is to say, totally — we don't like to live in debt. We hope to be break-even by the fall.

What are your goals for the future, and how do you plan to accomplish them?

We have a lot of big vision ideas, but our commitment is to freelancing professionals and the self-employed. We feel that they are the future of work, and that the right products and networks can not only solve problems for them, but facilitate fulfilling and enriching careers. There's a lot of buzz around contingent labor and the gig economy. We want to bring about the anti-gig. Again, the goal is not just helping out, it's leveling up.

What are the biggest challenges you've faced?

By far the biggest problem we've faced was admitting we had made some fundamentally poor decisions at the very beginning, and that correcting the course would entail almost starting over.

Some of this was born from cockiness and frugality: we thought we could do everything and save money in the process, and we had another company's success to validate us. But really we were making related mistakes that made it hard to untangle what was wrong. And because we'd sunk plenty into the product, we were reluctant to pursue the question.

We didn't have a real wake-up call until we were done — and that's a very expensive wake-up call. If we could do it over, I'd work hard to be more candid and to be more realistic about the expenses of starting a business, even a lean online business. Face the facts early — and always.

What were your biggest advantages? Was anything particularly helpful?

So far, our biggest advantage with Felix has been that we have very intimate insights into the working lives of our target users. Both my co-founder and I have been freelancers our entire careers — we don't know anything else.

Nothing beats bringing into existence, where nothing existed before, something you can be proud of.


We've also "leveled up" from subcontractors, to independent professionals, to the founders of an agency, so we can identify the needs of similar professionals who are on their way.

If you were to build a service for these users without knowledge of the industry and experience — especially for hairy things like payments — you would build a very different thing. We see many such services that are doomed for reasons that you'd know only if you worked in the field and knew the "facts on the ground."

What's your advice for indie hackers who are just starting out?

Simplify early, and simplify hard.

Figure out the core benefit of your product vs. the existing offerings and reduce until that is the only essence of the product. Then develop it. That's your foundation. If we had done this, we would have saved a year of work and, at minimum, tens of thousands of dollars, to say nothing of the opportunity cost.

And stick it out. One day will be jubilant; the next, discouraging. But nothing beats bringing into existence, where nothing existed before, something you can be proud of.

Where can we go to learn more?

Please visit our shit!

And feel free to email me at [email protected]!

tehowell , Creator of Felix

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Courtland Allen , Indie Hackers founder

  1. 3

    I'm a freelancer and my invoices are around 5K, so according to your website, I would pay 195.30 from each invoice, that doesn't seem like much value. Maybe consider a price cap?

  2. 2

    Good questions all! It'd be better stated that the team is about 10 people, mostly freelancers, and not all of them are full time. And we are working with some of the people that helped us set up the tutoring agency, but there's no double duty--i.e., Felix isn't a side project of the main business but a bet on the future of businesses like ours

  3. 2

    You have 2 Founders, 10 Employees and make $100 a month? Is that right? Why did you bring on so many employees so early?

    1. 2

      I'm willing to bet that these employees are really working for the original Tutoring agency. Felix is just a consumer version of their internal payment platform.

    2. 1

      I came here to ask this!

  4. 1

    Just wanted to say that it's quite nice to see the spectrum of monthly revenues here on IH. Some numbers can be envious, while others can be more humbling.

    Really hope to continue following your story, and good luck with everything.

    1. 1

      Thank you!

  5. 1

    Can you tell a bit more about the simplifying process? For example, what was the biggest difference between the first and second version?

    1. 1

      Absolutely. The biggest difference is definitely that the app is much, much simpler (I know that begs your question). To put that into perspective, we used to have an activity feed, 5 tabs, multiple levels of settings, a built-in invoice designer, and a complicated workflow in which invoices could be halted, edited, and resubmitted. All told it was dozens of screens. Now it's fewer than 10.

      And here's the big simplifying question: what is an invoice, and what benefit does it provide the sender? Following this train of thought, we were able to remove invoices from the app, in fact, though of course clients still receive them. And this makes the billing protocol much simpler as well, so the service is easier to understand.

  6. 1

    Er... If they cracked the 7-figure mark, shouldn't this say $100k/mo, not $100/mo? Might be a typo.

    1. 1

      I wish! The first figure was for my first company. Felix is still getting off the ground.

  7. 1

    Hi Pegasus! Thanks for the candid comment. In fact, most that fee is simple credit card processing. For the same reason, from a business perspective, the fee is hard to cap.

    I'll say, though, that if you're sending a single invoice to a single (good) client at long intervals, Felix is going to be overkill, and the time and convenience you gain might not be worth the fee. But if you have a number of clients with regular work and you want steady payments, you will very quickly more than make up for the fee of the service with the time and energy you save (and your clients will have a great and convenient experience too).

  8. 0

    No matter what if you're charging a card you're going to pay a percentage based interchange fee. This fee is extra high for this product because Stripe already makes money charging 2.9% and he has to make money on top of that. The solution as a freelancer is to not allow your clients to pay via card. Cash, venmo, or wire only.

    1. 1

      If your profit margins are so tight that 2.9% will make a difference, you need to raise your prices. As a freelancer, getting paid by card is the best way to ensure prompt payment. You will also lose business if you don't accept credit cards.

    2. 1

      Fairly true, though clients love paying with cards (with good reason--I love using my card as well). We have some developments lined up here though :)

      1. 1

        Also watch out for GoCardless - at some point, there will be a lot more pressure on the markup.

        1. 1

          Interesting company--thanks for the heads up