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Interview with a Successful Startup Founder

Quitting my job to make $5000/month with side-projects

Fabrizio Rinaldi
Fabrizio Rinaldi
May 6, 2020
Category of startup
Country of startup
Revenue of startups
Interview with a Failed Startup Founder

Quitting my job to make $5000/month with side-projects

Fabrizio Rinaldi
Fabrizio Rinaldi
May 6, 2020
Category of startup
Country of startup
Cause of failure of the startup

In late-2018, Fabrizio and Franceso quit their full-time jobs to create Superlinear and start launching apps. Their current focus is their recently-launched SaaS, Mailbrew, which allows users to create email digests on things they love. Mailbrew is now making $2k/month.



Hi Fabrizio! What's your background, and what are you currently working on?

Hi Failory, thanks so much for this interview. I’m Fabrizio, an Italian maker, designer, and filmmaker, currently working on Mailbrew full-time.

I’m from the South of Italy, and I’ve always been passionate about creativity and art. I studied filmmaking in Bologna, I have a background in 3D graphics, I’ve briefly worked in VFX and I’ve directed a short film. I also love photography and, in short, I’m obsessed with anything visual.

I’ve co-founded my startup Superlinear with Francesco in late 2018 when we decided to quit our job in a fast-growing tech startup based in Milan to go all-in on our side-projects.

Me and Francesco originally met on Twitter a few years ago and started working together on Boxy, an Inbox by Gmail client for Mac, without ever meeting in person. Boxy was a huge success and the beginning of a lasting friendship for me and Francesco.

Boxy on The Verge

In the company we joined (and left) together, we worked on apps used by millions of people, and an app I’ve designed was chosen by Apple to be installed and showcased in iPhone in Apple Stores worldwide. It was a crazy and beautiful experience, so quitting was a tough decision. 

Before deciding to quit that company, we actually launched a new side-project, Boxy Suite, a premium Gmail client for Mac. The launch was really successful, so after a few months, we finally decided to quit the job and co-found Superlinear.

Boxy Suite

Quitting a nice tech job in the business center of Milan was the scariest choice of my life, and the first few months after that were pretty confusing. My whole 2019 was a rollercoaster, and me and Francesco didn’t just work a lot, but also traveled more, and embraced more personal endeavours as well.

Luckily between our personal savings and the revenues from the Boxy Suite launch (~40k USD in the first 3 months), we had some leeway to get things started on our own.

Currently, our main focus is on Mailbrew. We launched it on March 3 after around 6 months in private beta, which felt like an eternity.

Mailbrew is our most ambitious project to date: it’s an app that saves you hours of time by sending email digests about your favorite topics, on your schedule

Users can pick their favorite sources (Twitter accounts, Subreddits, Blogs, anything), select a schedule, and receive beautiful emails with the best content from these sources — this way they can unplug from feeds and stop checking multiple websites every day.

Mailbrew Banner

I reached out to DHH asking him to try it during the beta, and he’s been really supportive since then. He even tweeted

“I've been using Mailbrew to keep up with Twitter peeps who don't post often, but whom I'd really hate to miss what they have to say. It's pretty awesome. In many ways, Twitter-over-email is the healthier Twitter!”

Having DHH as a user and testimonial was incredibly motivating while working on the beta, and in these few months we’ve found other engaged users which fell in love with Mailbrew, and that gave us confidence that we were on the right path.

Our very first paying user was Pat Walls. We’ve always been inspired by his projects and work ethic, so it was great to have that kind of validation early on.

What's your backstory and how did you come up with the idea?

In 2019, during our digital nomad stint, we’ve launched a newsletters network called Unreadit. It received a warm welcome online, great testimonials, and has been growing steadily since launch.

Basically, we’ve created different newsletters with the best content on many topics, sourcing from Reddit. Initially, they were all manually curated, while now we’ve automated most of them, and just edit the most popular ones.


It started generating revenue from sponsorship, but it’s really unpredictable: some months $0, others $1000. We also felt like it was time to take it to the next level and let users craft their own newsletters.

That’s when we realized that this is something that could provide real value to people, and we wanted it ourselves: an app to create beautiful automated newsletters on any topic.

So we started working on Mailbrew. Initially, it lets you create newsletters mixing any subreddit and RSS Feed, and offering few customizations. During the private beta, we added many features and possible customizations, and new sources like Twitter, Hacker News and YouTube.

Mailbrew's dashboard

What started as a “tool to create automated newsletters” slowly became much more ambitious. A way to truly unplug from feeds, keep in touch with things and people you care about, and really be on top of your game by getting essential information on any topic, every day or week.

How did you build Mailbrew?

When we first started working on our side-projects, me and Francesco were a pretty standard designer-dev duo. Lately, the lines have been blurring a lot, a while Francesco still does the bulk of development, I started working on the frontend of our apps, which are built with React.

We’re pretty fast now, and we can build React prototypes of our ideas quickly, especially since we’ve created our own UI Kit, which is a set of components that are easily customizable and reusable. All these components are styled from a single, centrale JSON file. This means that when I change the branding of the Mailbrew.com website, even heavily, I can then copy the necessary parts of the UI Kit configuration, paste inside the Mailbrew app config, and see the app magically transform according to the new branding.

Mailbrew has been particularly challenging though since each user is able to create and customize email newsletters, so we needed a newsletters template system, a backend that can generate them, a frontend that displays a live preview of the newsletter while you edit it and so on.

In this regard, having a close beta proved to be essential since the first version of the apps was very rough around the edges, and also way slower than it is now. We’re much more confident releasing it to the public after these months of work and fine-tuning.

Another big obstacle has been positioning. While we had our own idea of what Mailbrew is and who it is for, seeing our first few hundreds of users using it was essential in understanding what the value proposition is. 

Not, for example, during the onboarding, we ask you what’s your role, and then after a few weeks of usage, we ask you to take a survey asking you a few questions that help us understand what’s Mailbrew for you. All of this, together, was incredibly helpful to craft a great landing page and shape the product you see today.

How did the launch go?

I think that doing a long private beta before has been a key element in launching successfully. There are many things that, in hindsight, proved to be essential to have a great experience with the product and get great value from it.

When you’re working on something, it’s so easy to take things for granted and lose sight of the big picture. The private beta helped us take things slowly, analyze our key metrics properly, understand our users and what they needed, and also present the product in the best possible way.

People who requested access to the beta came from various links on unreadit.com, an email we sent to our lists, and some tweets. We hand-picked the first handful of users from this and had some Zoom calls to get them on board and gather valuable early feedback. These calls proved to be essential to get a feel of the product in the user’s hands, develop its positioning, and spot key issues and weaknesses.

After a few weeks, we started letting random people in (100-200 at a time) to start tracking metrics and get more feedback in bulk.

So, when we launched, we already had hundreds of people in the app and gathered so much feedback on the product, the email digests, our positions, etc. This way, on launch day, we really felt confident and prepared for everything.

Before launching we settled on a free trial without a credit card, so everyone could get a taste of the real product, without commitment. We’ve had 2000+ signups and we made it to the front page of HackerNews (finally!). Product Hunt surely played a role, but I feel like it’s not as important as it was a few years ago.

Mailbrew's launch

Francesco published a great thread on our launch if you want to read more.

Now that some time has passed, I feel like I can confidently say that launched at the right moment. More months in beta wouldn’t have been wasted: we really needed to get the product out there, validate the monetization, and see how people would react. The response so far has been overwhelmingly positive.

A few weeks have passed, and we crossed 40 paying customers, with a high percentage of yearly plans and even a few lifetime licenses sold (for $250 each).

What are your goals for the future?

We’re really betting a lot on Mailbrew. It’s not just another project, another thing we want to try before going to the next one. We’re treating it as its own startup, investing nearly all our time on it, and trying to keep track of the right metrics to make sure we’re always focusing on the right things.

Monetization-wise, while we started with a pretty convoluted 4-plan paywall, and experimented with a trial with credit card, before launching we decided to simplify everything and go with a limited Free plan, and a single comprehensive Pro plan that costs $10/m. Users appreciated this change, and one person converted instantly to the Pro plan when seeing the new paywall.

We even had users like Pat Walls who started paying for Mailbrew when it was still in its early stages and very limited, and that was a very nice indication that this was indeed something people would be willing to pay for.

Going forward, we want to make sure to not add features and sources for the sake of it, while instead being more high-touch than usual with customers to understand what they really need.

What were the biggest challenges you faced and the obstacles you overcame?

A huge weak spot for us has always been growth and marketing. We had multiple successful launches that made us rest on our laurels a lot, while we could be much more successful if we invested more time and energy in finding and growing our customer base.

Even with a product like Boxy Suite (well positioned on Google and appealing to a large audience) we didn’t really do much content marketing, SEO, and growth for a lot of time, and this was a big missed opportunity. Luckily we started doing that later on and we’re starting to see results.

Another challenge we’re always facing is to find the perfect work/life balance, allowing us to pursue personal passions while still working side by side and being productive and efficient. We’ve surely improved a lot in this regard, and I feel like honesty and good communication between co-founders are key here.

Personally, I think my most challenging months were right after I quit my job. Suddenly having so much time for myself, and a world of possibilities, paradoxically made me depressed and unmotivated. I had to rebuild my routines, understand my priorities, and basically find out what I really wanted. That’s why 2019 has been such a transformative year for me, while I feel like 2020 is the year where I’m reaping what I sowed in the last few years.

Which are your greatest disadvantages? What were your worst mistakes?

If I had to pick a single big mistake we repeatedly did, is rushing our launches. Sometimes we worked for weeks or even months on a product, only to then plan and launch it in a few days.

This means not taking advantage of a lot of low-hanging fruits and not really playing all your cards. We surely put much more thought into it now, and we also launch more often. Taking the time to prepare to launch doesn’t mean you shouldn’t do it every few months.

What are some sources for learning you would recommend for entrepreneurs who are just starting?

My recommendation is just to keep your mind open. Sometimes I get my biggest insights from essays and books that have nothing to do with entrepreneurship and startup. Sometimes watching a great film and listening to a great conversation are more helpful than trying to find hacks and shortcuts.

For instance, I love Malcolm Gladwell’s books. They are extremely insightful and dig into parts of the human mind and nature that can be really enlightening.

Where can we go to learn more?

I have a personal website where people can learn a bit more about me, and I definitely recommend checking out Mailbrew. I’m putting my soul in it and every new person that uses it and gives me feedback means the world to me.

I’m a Twitter junkie so maybe you can follow me there.


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