Joschua clocked out of his data job for the last time on a Friday.
Two hours later he was back at a desk. His own desk this time, working on his own product until 1am.
Nobody made him do it. That's the tell.
I found his story on the Starter Story Build podcast and it's one of the cleanest examples I've seen of how to quit your job to build a startup without gambling your life on it. Joschua is 24, from a small town in Germany, and 15 days before this interview he went all-in on Postel, an X content tool he's building with two co-founders he met on Twitter.
He's met them in person exactly twice.
Here's the full episode. Watch it, then let's break down the math he ran before quitting, because that math is the whole lesson.
It started with a Reddit post, not a business plan
Joschua studied business admin, realized too late he'd never build a career on it, and landed in a business intelligence job through what he calls a happy accident.
Two years in, he was fed up. So he started doing small side projects again, like he did in high school.
One of them went viral on Reddit.
He wanted to share what happened next, so on September 1st last year he made his first ever post on X. No social media before that. Nothing.
That one post pulled him into the build-in-public scene. Nine months later he had a product, two co-founders, paying users, and a resignation letter.
Sequence matters here. He didn't quit to find an idea. The idea, the audience, and the revenue all showed up while he still had a salary. If you're at that earlier stage, I wrote up business ideas you can build without quitting your job for exactly this reason.
The ghostwriting hack that became the product
Building in public got Joschua noticed. Freelance clients started asking him to ghostwrite their X content.
It got to be too much work, so he built a hacky workflow: one giant ChatGPT prompt plus scraped posts from big accounts in each client's niche.
Then he met Robin, a fellow German who ran a small community for builders. Joschua ghosted him at first (his words, he's not a community guy). They finally hopped on a call. By call three they realized they wanted to solve the same problem.
The GitHub repo was created the next day.
That hacky ghostwriting workflow became Postel: connect your X account, it learns your voice, you add creators whose style you like, feed it a YouTube video or a blog post, and it gives you angles, threads, and a scheduler.
Notice what the product is. It's not a shiny idea he brainstormed. It's a workflow people were already paying him to run manually. You can't fake that kind of validation.
$50 for a year: the launch offer that got 10 customers in a day
The first version was scrappy. They built it on a boilerplate starter kit to skip auth and billing setup, showed it to builder friends, and got harsh feedback. Good. They wanted harsh.
At launch they made a no-brainer offer: a year of access for about $50. Roughly $4 a month.
Two posts on X. First 10 paying customers the same day.
Three weeks after launching the MVP, Joschua posted in the Starter Story community: $200 MRR, 17 users. Small numbers. Real numbers.
Then came the part most people skip.
100 personalized Looms in one weekend
To get past his warm audience, Joschua manually researched over 100 X accounts that were active but struggling with content. For each one he recorded a personalized Loom, screen-sharing their own profile: here's what you're doing, here's how Postel could help.
Over 100 videos. One long weekend.
Most people never replied. But he noticed something in the data: they signed up anyway.
That insight changed his whole outreach model. The friction to sign up is lower than the friction to reply. So he stopped optimizing for conversations and started optimizing for getting the link in front of people.
His cold DM numbers, for the record: about 5% reply rate. Five answers per 100 sent. He treats DM scripts like experiments, finds the one that works, then systemizes it.
And every single person who signs up gets a manually researched, personal welcome DM offering help. He says that one gets a 100% positive response rate.
None of it scales. It got him his first real users anyway.
The numbers that made quitting rational
This is the section to steal.
Joschua didn't quit on a feeling. He quit on a stack of signals:
→ Postel was growing 11 to 15% week over week. Hold that rate and it's on a path toward $10K MRR by year end (he admits that's optimistic, growth gets harder).
→ A design agency founder with more followers than both co-founders was using it daily to write posts that bring him clients. That's a painkiller, not a vitamin, as he puts it. Content with a business return attached.
→ PostHog showed one paying user spending an average of 1.5 hours a day inside the app.
→ Four weeks after launch, a user sent a Loom review that ended with "I would love to own a part of it." Two more people floated angel round intros.
→ And the big one: 24 months of personal runway, saved by living frugally for three years while employed. He's selling everything he owns and moving to Southeast Asia to stretch it further.
Revenue signal, retention signal, investor signal, and two years of runway. He told Gus he was maybe 70 to 80% sure there was something there.
That's a responsible leap: stacked evidence plus a survival plan, not certainty.
I've watched founders do the opposite: quit with 3 months of savings and a landing page, then make panicked decisions by month two. Panic makes you ship the wrong things for the wrong reasons.
What happened after he clocked out
His colleagues asked where he was working next. Telling them "an app for Twitter I'm building with two guys I met online" got him some looks. Friends called him crazy. You have a salary. You have benefits.
His close circle came around: if you're doing it, go all the way.
The feeling he describes after walking out wasn't fear. It was mental space. Juggling a day job and a startup splits your brain in two, and half your energy goes to a company that isn't yours.
Then he did something smart for a self-described camera-shy guy: he started a daily founder vlog on TikTok, day one of being jobless. He was on day 16 at recording. Forcing the discomfort on purpose.
If you're still at the day-job stage, this is why I keep telling founders to build in public before they need the audience. Joschua's entire company exists because he documented a Reddit win publicly. His co-founders, his first users, and his ghostwriting clients all came from posting.
His advice to his younger self
Gus asked what he'd tell himself before starting Postel. Three things stood out:
Move faster and stay focused. The first version tried to serve Twitter, Reddit, and more at once. It slowed the build and made marketing muddy, because no clear person needs all of it. One platform would have moved faster.
Smoke test before you build. He wishes they'd launched a waitlist for the idea before writing code, just to measure attention.
Validate the pain, not the solution. Your first build will be far from the final product anyway. Early on, you're collecting proof that the problem hurts, then iterating your way to the answer. Talk to users constantly, and build a system that turns each piece of feedback into a shipped feature.
Obvious advice is obvious for a reason. He said that himself, and he's right.
FAQ
How much runway should you have before you quit your job to build a startup?
Joschua saved 24 months of living costs before quitting, built up over three years of frugal living, and he's moving to Southeast Asia to stretch it further. You don't need his exact number. You need enough that you're never making product decisions out of panic. For most founders that's 12 to 24 months of bare-bones expenses.
How do you know when it's time to quit?
Look for stacked signals, not one big one. Joschua had week-over-week revenue growth (11 to 15%), a power user relying on the product daily for business results, inbound investor interest, and long session times in his analytics. He was still only 70 to 80% sure. If you're waiting for 100%, you'll never leave.
Can you build a startup while working full time?
Yes, and Joschua's story is the proof. He built his audience, met his co-founders, landed ghostwriting clients, launched Postel, and reached his first paying customers all while holding a business intelligence job. The day job funded the runway that made quitting safe.
Did Postel make money before he quit?
Yes. First 10 paying customers on launch day with a $50-per-year offer, $200 MRR three weeks in, and steady double-digit weekly growth by the time he resigned. Small revenue, but real, and trending the right way.
Steal the sequence, not the story
Side project → audience → co-founders → paying users → runway → then quit.
Most people run it backwards. They quit first and hope the rest shows up.
Every week on the Profitable Founder Podcast I dig into how real bootstrapped founders actually made these calls, the numbers behind them, and the parts that hurt.
