Cosmin Rusu

Transforming Visions into AI MVPs & Products | Founder @Duty Ventures | Ex {Google, Apple and Amazon}

Hi, I’m Cosmin, the Founder and Lead Engineer of Duty Ventures. 

After some experience as a software developer in companies such as Google, Apple, and Amazon, I decided to launch my project.

With several former colleagues and college friends, we launched our own startup specializing in software development for entrepreneurs and customers needing software development services. 

Duty Ventures is all about developing software products from start to finish, thanks to the experiences we have all acquired in the past years.

One of our most successful services is aimed at entrepreneurs and early-stage founders, for whom we provide an MVP-builder service getting their product from 0 to 1 within weeks!

However, our services are not limited to that. The teams we create do much more than just create MVPs and are able to adapt to the different technologies requested, all of this in an agile way.

Our most recurrent services are the following:
- MVP creation
- Custom Software Development
- Blockchain Development
- Mobile Development
- Checkout pages
- E-Commerce

And our most used technologies are:
- Ruby on Rails
- React
- React Native
- Java
- NodeJS


If you want to learn more about how we can help you, head over to: https://dutyventures.com


Phone: (+1) 669 200 9568 / (+40) 754 973 314
Email: cosmin@dutyventures.com

Founder & Lead software engineer

I'm leading a software development agency focused on fast iterations. Most of our clients are shipping more features, responding faster to support tickets, and have accelerated growth because of us.

We focused on HealthCare a lot lately due to the accelerated digitalization in this industry. I am a strong believer that we can make healthcare more technically advanced via pure software. 

In terms of technologies, our previous projects involved Ruby on Rails, React, React Native, Scala, Java, Kubernetes, GCP, AWS (ECS, RDS, AKS), Stripe Connect, HIPAA compliance.

Some of our previous clients: 
- Spotify
- Colgate
- Go4Ellis (incl. HIPAA compliance)
- KindBody (+1 HIPAA)
- NXT Sports
- Noom (Healthcare)
- Mochila Fulfillment
- 3Step
- Mylk Guys (YCombinator)
- NLV Productions
- SH Technologies
- One Step Software (Techstars)
- Ergodic Labs
- Med Prep
- Testing Psych
- Abundance Digital
- Tookitaki

I upgraded to a Standing Desk half a year ago! Worth it? Not really - I find I very rarely use it, and recently just thought about it... We tend to stick to what we're comfortable with, to what we are used to. It's hard to get into a new habit. But once it becomes a habit, it's almost like second nature. In 2026, I plan to use it more often.

Product-minded Devs | Founder @Duty Ventures | Ex {Google, Apple and Amazon}

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Are you behind on your Stripe API upgrades? Be careful! Stripe is sunsetting some very important and widely used features.

Stripe::Charges, Stripe::Sources are being deprecated and replaced with the more modern equivalent, the Stripe::PaymentIntents and Stripe::PaymentMethods. While you can still use them, you should plan to upgrade your integrations to avoid imposed deadlines during your busiest season...

In fact, one of my long-term clients started contracting us for a challenging Stripe Connect upgrade, back in the days when Stripe rolled out mandatory Know-Your-Customer (KYC) flows. 

To learn more, keep an eye on the Stripe Change Log: https://lnkd.in/dBm7PKvf

In B2B sales, I learned a valuable lesson: it's easy to focus on getting new customers, but super hard to get them to sign up. However, it's hard to focus on existing (or past) customers, but super easy to get them to sign.

Learning from others' mistakes! Here's another example of failures in marketing that will lead to bad outcomes.

I got a cold email from a company selling cybersecurity services. I clicked on their website, and I got this pop-up.

I get that sometimes marketing emails don't go through strong security checks, but you can imagine how a lead would react if you send such emails.

How do we work remotely as a team? What tools to do we use? Let me break it down to you.

- Communication: Slack
- Email: GSuite
- Meetings: Google Meet
- Project Management: Trello - very simple and clean. For more complex projects - JIRA
- Code Editor: Windsurf

That's it - nothing fancy, nothing complex. This is our "productivity" stack. Next, it's up to the individual to figure out what works for them. We don't want to force anyone into using anything that they aren't excited about.

Are you rich when you make 25x your annual spending? Is that the "golden ratio" of financial independence?

Here's a great hack I naturally learned that improved my sales skills:

Whenever you get a cold email, cold LinkedIn message, or even a cold call, answer and be receptive - be the buyer!

I'm almost always doing this, just to see how the best salespeople perform. If I forget about them, do they follow up? How many times? If I simply forgot to sign the papers, how do they gently ask me to sign?

I'll give you an example: I get called a few times per quarter from mobile carriers that are trying to sell me their phone services, like SMS, voice, and internet. I almost immediately say:

- I'm not interested - I already have an unlimited cheap subscription, thanks! 

However, last time I got a call, I asked them to tell me more, and asked:

- How are you better than this other subscrption I have?

Next time I send a message regarding custom software development work, I'll understand that most people like where they are at and don't want to change their teams. However, if you approach the conversation from their angle, you'll find that if you can tell them something that they don't know already, you might at least have a small conversation.

Doing this will make you more empathetic to your next clients, and you'll learn faster what works, and what doesn't work in sales.

Not to mention you'll see how easy it is to "slip" through the funnel 😆!

Careful - we re getting replaces with cached code written by AI - so all our code will have the same bugs and issues that we will have to fix… that would be a cool service businss idea: bug fixes for your AI agentic coder

Cute how devs think they’re gaming the system with $200/month for unlimited Claude Code. ”Oh, I’m burning $2K in tokens with 6 Claude Codes before breakfast!”

Buddy, you’re not burning tokens. You’re burning markup.

I wired Claude Code into a dedicated vLLM to see what’s really under the hood. Six hours of pure coding and debugging later:

- 47M prompt tokens
- 45M prefix-cache hits
- 96.39% cache hit rate (token-weighted)
- Actual compute: 1.3M prefill + 300K generation tokens

That’s not GPUs working hard. That’s a cache with delusions of grandeur.

Anthropic’s “subsidized” coding plan isn’t subsidized; it’s a cache lottery. When they serve you a well-quantized Haiku/Opus hybrid that’s 96% memorized boilerplate, the marginal cost rounds to zero. The limits are fake scarcity. The $100 and $200 tiers are merely psychological anchors.

You’re not paying for compute. You’re paying for the feeling of unlimited power while they throttle you at 5 hours/week limits to protect GPU margins.

Agentic coding is a brilliant pricing hack. Just don’t confuse it with actual token economics 🤡

Make sure you own your AI. AI in the cloud is not aligned with you; it’s aligned with the company that owns it.

I help B2B founders book 3-5 sales calls EVERY single week within 60 days. 

Most founders I talk to on are struggling with:

- What type of content to post.
- Don’t know how to get leads. 
- Don’t know how to turn leads into sales calls. 

My simple LinkedIn system helps them solve that:

1. A profile that positions them as an authority.
2. Content that builds trust with their ideal clients.  
3. Outbound DM’s that book 3-5 sales calls a week. 

The result?

- Your ENTIRE marketing is done for you. 
- A constant flow of leads EVERY single week.
- Your dream clients choosing you over your competitors. 

It’s the exact system that helped:

📌 Abhijit: Grow to 2000 followers in 60 days. 
📌 Matthew: Closed a 120,000 deal in 27 days. 
📌 Mark: Generated 2 inbound leads in the first week.

My system DOES work. 

If you’re committed to turning LinkedIn into a consistent revenue stream...

Click “Book an Appointment” to see if I’m the right person to help you.

Omkar Rane

1372 days ago, I lost my DREAM job.

Today, I make more money freelancing on LinkedIn. 

I was 23 and fresh out of university. 

I landed a job at the biggest marketing agency in the world.

Huge brand names. Fancy office. Massive team. 

In my head, I thought I was on the right path. 

But three months in, reality slapped me in the face.

Let me explain…

I was working as an account manager - basically paid to talk all day.

Constant meetings. 
Back-to-back client calls. 
Endless office politics.

The job was basically designed for an extrovert.

But I’m an introvert. Always have been.

I thrive doing deep, solo work. 

So everyday felt like I was performing a role that wasn’t for me.

Six months in, my boss called me to his office.

“Your work isn’t up to the mark. We’ll have to let you go.”

I won’t lie, It did hurt a bit. 
But honestly? I also felt relieved.

Because deep down, I knew this job was never meant for me.

Fast forward 3 years…

I make more money freelancing on LinkedIn than I ever did at that agency.

But more than the money, the work I do feels more ALIGNED. 

I’m helping founders build personal brands that actually bring them clients.
And for the first time in my life, I’m doing work that feels meaningful.

Getting fired didn’t end my career. 

It just redirected it.

Helping Founders book 3-5 sales calls EVERY single week within 60 days

97% of founders will FAIL to sign clients on LinkedIn in 2026.

Not because LinkedIn is broken.
Not because the algorithm has changed.

But because no one trusts them.

A few years ago, LinkedIn was simple:

- Post generic content
- Wait for inbound opportunities. 
- Never touch the DMs to reach out. 

But that window is closed.

In 2026, the competition is higher and reach is lower.

And people are numb to AI-written, copy-paste posts.

The founders I speak to don’t get results on LinkedIn not because they lack expertise. They don’t get results because they sound like everyone else. 

This is what your ideal clients actually want to hear from you now:

1. Your personal stories
2. Your values and beliefs
3. Who you are outside of work
4. Your failures, not just your wins
5. What building the business really looks like
6. How you think and why you make certain decisions.

Because people aren’t buying from company logos anymore.

They’re buying from people they TRUST.

And trust isn’t built just by sounding like an expert. 

It’s built by sounding human.

Helping B2B Founders & CEO’s Scale Their Personal Brand On LinkedIn With Content + Outreach

I turned 26 last week.

I've failed at almost everything I've tried.

At 17, I launched a dropshipping store. Couldn’t make it work.

At 21, I opened an online thrift shop. Shut down in 9 months.

At 22, I landed a job in a marketing agency. Fired in 6 months.

At 23, I travelled solo to "find myself" for 3 months. Came back just as lost.

At 24, I pivoted to UX design. Quit 2 months in because I hated it. 

At 25, I joined my family business. Safe and stable but soul-crushing.

At 26, I’m building my freelance business and doing work I actually enjoy.

Most of my friends are engineers, consultants, and doctors. 

They have titles that make their parents proud.
While I have a resume of failures that looks like I can't commit to anything.

But here's what I've learned:

Some people find their thing at 22. 
Some of us need to burn through five wrong answers first. 

For years, I thought there was something fundamentally wrong with me.

Turns out the only mistake was doing things I was never meant to do.

4 months ago, I started building my freelance business on LinkedIn. 

I've signed 3 clients already. Nothing crazy. 

But for the first time in my life, I'm doing something I actually like. 

I’m 26. Still figuring it out. Still failing forward.

And I've never been more sure I'm on the right path.

PS - How many failures did you have before you finally found your path?

"I spent $1,200 on a ghostwriter and could only use 3 posts.”

That's what a founder told me this week.

He was working with another ghostwriter before.

The posts were fine on paper.

But when they went live, they didn’t sound like him at all.

And this is how a lot of founders waste money.

They spend $500–$1000 on outsourcing their content.

The posts look polished, but something feels off.

Because many people calling themselves ghostwriters aren’t actually writing. They’re just prompting an AI, polishing the output, and sending it over.

The result?

A founder with a robotic voice that doesn’t reflect how they speak. 

Your LinkedIn voice isn’t just random words.

It’s your entire personality, your tone of voice, and your point of view.

An introverted founder sounds like they're thinking out loud.
An extroverted one makes bold statements that pull you in.
A technical founder breaks down how things actually work.

So you have to understand how the founder ACTUALLY thinks and speaks. 

And most ghostwriters miss that.

So if you’re a founder thinking about outsourcing your voice to someone else.

don't start with "who can write posts for me."

Start with "who actually understands how I think and sound.”

My client’s LinkedIn reach dropped 50% overnight.

I didn't see it coming. 

His previous posts? 
50+ likes consistently.

His latest one? 
Barely crossed 20 likes. 

Similar content but half the reach.

Here’s what's actually happening:

LinkedIn has replaced its old algorithm with a new AI system called 360Brew.

The OLD algorithm mostly cared about numbers.

But the NEW algorithm cares more about relevance.

Let me explain..

- Engagement pods? LinkedIn will detect that.
- Emojis and hashtags? They make your content look spammy.
- Posts that don’t match your profile? It will not get any reach.

So if your headline says "SaaS Founder" but you're posting travel content, wellness tips, and motivational quotes, you’re sending mix signals to the algorithm and your reach will drop.

Here’s what you should do with the NEW update:

1. Quit the engagement pods.
2. Stick to one topic per post.
3. Stop using hashtags and emojis.
4. Post about what you actually do.
5. Engage with potential clients, not viral posts.

If your content isn’t performing, it’s not entirely your fault.

But it is your job to adapt.

The rules of LinkedIn have changed.

RELEVANCE is the new currency.

I charged a client $500 to grow his personal brand on LinkedIn. 

60 days later, he signed a $950,000 project.

That's a 1,900x return on investment. 

He runs a B2B manufacturing company in India. 

No fancy product. 
No big marketing budget. 

Just STRATEGIC LinkedIn growth. 

Yet, this is what I hear from founders every day:

"$500-1000 is too much to spend on LinkedIn growth"

Let me be direct about this.

If $500 feels expensive, you're not doing the math right.

Because you need ONE client to make your investment profitable. 

And If you can't see how LinkedIn could get you one client, you’re either:

1. Not actually serious about LinkedIn
2. Don’t have the right strategy in place. 

Because growing on this platform isn't about luck. 

It's about having SYSTEM: 

- Content that builds trust with your audience.
- Outreach to the right people willing to pay. 
- Commenting to drive engagement. 

The founder I worked with just committed to the process.

60 days later, he closed a client bigger than his entire marketing budget.

So stop debating if "Is this too expensive?"

Start asking "How much money am I leaving on the table by waiting?"

Because while you're debating the cost, your competitors are closing deals.

PS - If you’re a B2B founder who wants to grow on LinkedIn and bring in more revenue, DM me “CONTENT” or book a free call from above.

A founder came to me with a DEAD LinkedIn profile.

His FIRST post hit 149 reactions. 

12 days later?

Another post hit 108 reactions. 

But what mattered wasn't just the numbers.
It was people in his industry that started reaching out to him.

Here’s exactly what I changed when we started working together:

1. We optimized his profile.

Built his profile like a landing page to book more sales calls.

2. We posted trust-based content

Posts that highlighted his experience, built credibility, and made the right people pay attention.

3. We started engaging strategically with his ICP.

Everyday we started commenting on his ICP’s posts that added value. 

The result?

- 116 new followers.
- 2 viral posts and one caused a real debate in the comments.
- 3 inbound opportunities from people already aligned with his work.

So he didn’t just grow his LinkedIn account.

He started getting inbound opportunities leading to more revenue.

PS - If you’re a B2B founder who wants to grow on LinkedIn and bring in more revenue, DM me “CONTENT” or book a free call from above.

The founders winning on LinkedIn don't have the best product. 

They have the best STORY.

Most founders I speak to are still using LinkedIn like a company brochure.

They are trying to show their latest features, updates, and product launches. 

And then they wonder why nobody wants to buy from them. 

But in 2026, people don’t just buy the best product.

They buy your STORY.

These are the stories your customers actually want to hear from you:

1. What you actually believe about your industry.
2. How you think and why you make certain decisions.
3. Your values and beliefs, and who you are outside work. 
4. The moments where you failed and things didn’t work out.
5. What your week actually looks like running your business. 

Because people don’t just resonate with your product or business. 

They resonate with the story behind it. 

If you’re a B2B founder who’s building a brand on LinkedIn,

Don’t just talk about what your company does.

Start talking more about YOU.

I wrote a post for my client that got him DESTROYED in the comments.

It also became his highest performing post.

Last month, I took over a client’s LinkedIn account.

He runs a security company in the US.

His controversial industry take?

Police officers shouldn’t be hired to do security work.

As expected, people lost their minds in the comments.

But that post became his highest-performing post to date.

Here’s what came out of it:

- 150x increase in profile views. 
- 60+ comments of people debating in the comments.
- Multiple business conversations from people who agreed with him.

This is the part most founders miss:

You don’t make money by being liked by everyone. 

You make money by taking a stand on what you believe in. 

The people arguing in the comments? 
Not his customers and were never going to buy from him.

The people who reached out? 
His ideal clients who finally heard someone say what they were thinking.

Because people don’t just bond over things they agree on.
 
They also bond over things they DISAGREE on.

And relationships on LinkedIn work the same way. 

So if you’re a founder and your content feels “safe,”

It’s also probably safe for your audience to ignore. 

PS - If you’re a B2B founder who wants to grow on LinkedIn and bring in more leads for your business, DM me “LEADS” or book a free call from above

People don’t buy your product or service.

They buy YOU.

In 2026, nobody gives a shit about your latest product feature.

What they actually care about is the HUMAN behind the company.

Because everyone is already selling something similar to you.

Yet most of the founders on LinkedIn post the same nonsense:

- Product features
- Company values
- Excited to announce posts

Then wonder why nobody's buying from them.

Let me be honest..

Your ideal clients aren’t scrolling LinkedIn thinking:
“Wow, great SaaS roadmap.”

They’re thinking:
“Can I trust this person with my money?”

And trust doesn’t come from sounding like everyone else.

It comes by showing them the REAL you:

1. How you think under pressure
2. How you make decisions
3. What you believe, not what’s trendy
4. Who you are outside work
5. How you handle mistakes and uncertainty.

The stuff which feels uncomfortable to share.

Which is exactly why it works.

In 2026, people don’t buy the best product anymore.

They buy the person they TRUST the most.

taplio

The Battle

Cosmin Rusu

Omkar Rane

Followers

Posts

Engagements

Likes

Performance ScoreCosmin Rusu's LinkedIn Performance

Performance ScoreOmkar Rane's LinkedIn Performance

Ready to grow your LinkedIn presence?

taplio

The Battle

Cosmin Rusu

Omkar Rane

Followers

Posts

Engagements

Likes

Performance Score.css-goub6s{font-size:var(--chakra-fontSizes-md);font-weight:500;color:var(--chakra-colors-gray-600);display:block;margin-top:var(--chakra-space-1);}Cosmin Rusu's LinkedIn Performance

Performance ScoreOmkar Rane's LinkedIn Performance

Ready to grow your LinkedIn presence?

Performance ScoreCosmin Rusu's LinkedIn Performance