Replace your startup's chaos with blissful clarity

Do you wish you had a magic crystal ball that tells you what to do every day to achieve explosive startup growth? Bad news, it doesn’t exist. But my smart workflows and frameworks are close enough.

Subscribe to my newsletter to get one perspective-flipping email every week.
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.
Behind Experimenterra

Hi! I’m Justi CG

I'm on a mission, and it's a biggie: to equip marketers and founders with clear-as-a-hell frameworks, strategies and AI wizardry that will help them get unstuck and work smarter, not harder.

Justyna Ciecierka
My offer

Products & Services

Packaged Services

Need a top-class expert's assistance to get things going? Choose a package that's best tailored to your needs. Clear scope, realistic outcomes, no retainers.

Learn more >>

Digital Products

I've got a lineup of free and paid products ready to be your GPS through the startup maze. They're all about crystal clarity, impact-driven and human-centric hustle.

Learn more >>


Learn my frameworks, workflows and mental exercises that will put you into action mode instantly even if you have no prior marketing experience.

Learn more >>

I worked with these folks

And they loved it. But don't take my word for it.

Justi is wonderful! I've worked with her many times, including working as an employee in the company where she was Head of Growth. She has lots of experience in all things growth marketing and building a team. In a quick call, she helped me to become aware of the top things I need to keep in mind during the restructuring of our marketing and growth teams.
Manuel Brandt
CEO @ Blogtec
My mentorship with Justi was one of the most fruitful ones I have ever had. She is super smart and good to carve out the gaps in your plans. Absolutely recommended
Luka Karsten Breitig
CEO @ The Happy Beavers

I've reached out to Justi with a broad problem: scaling content marketing. During our 30-minutes session, she quickly identified bottlenecks in our current process and offered practical advice on how to get past them. Thanks so much for the help!

Bogdan Pol
SEO Growth Strategist @ Scale
Justi was absolutely amazing. We walked through our onboarding flow and several other emails. She took the time to prepare the session, asked so many great questions, gets straight to the point and forced us to zoom out to what would drive impact. Justi's superpower is that she really puts herself in the shoes of the customers, keeps things simple and from there gives concrete action steps. We have a whole list of inspiring ideas and she even sent notes afterwards. Can't recommend talking to Justyna enough!
Daphne Tideman
Growth Consultant

Justi helped us identify our subscription business's weak spots and improve our conversion rates. She provided us with valuable insights into our target audience and challenged our way of thinking.

Mariah Freya
CEO & Founder @ Beducated

Justi helped me create my growth marketing strategy. She showed the possible options without making me commit to anything upfront which made her offer an absolute no-brainer.

Martin Hoeller
Founder @ In Your Face

I was just missing one big piece and that's why I was struggling. Justyna helped me figure out how to quickly fill in that piece with only a small amount of effort and time. Yay! Well worth the time I took to speak with her. I'm still floating with excitement from hearing her advice and knowing how to implement it.

Anita Toth
Chief Churn Crusher

Justi is a fantastic mentor. She helped me get to the root cause of my confusion regarding experiments and ultimately get a clear direction on it.

Growth Strategist

Justi is really intelligent, extremely resourceful, and has so many creative ideas. She can put it all to words in an amazing way and she knows how to connect with any stakeholder. Besides that, she will challenge everyone to make things actionable.

Benthe Metselaar
Growth Consultant
Justi is my go-to-person for growth. When we teamed up for the first edition of Upstream festival, she demonstrated a unique combination of intelligence, creativity and grit. Looking forward to work and learn with her again.
Lars Crama
Private Lead | CXO | Supervisory Board Member

Justi truly helped in implementing new marketing ideas and processes that support our business strategy. We value the comprehensive approach to testing, identifying, and validating the most efficient strategies for gaining new business partners. Thanks to her, we not only met our goals but also found ourselves inspired by her innovative approach and mindset. It changed the way how we organize new marketing initiatives. The value we gained from their collaboration extended well beyond mere numbers on a business dashboard.

Marcin Joka
CEO at Photon Education
Justi's enthusiasm, challenger mentality, and open-mindedness were all instrumental in the growth of our marketing operations. Her perseverance and positiveness made a clear impact and largely influenced the team dynamics. Always prepared to stand up for what she believes is right for the business, and always a step ahead of the conventional digital marketing. Justyna is an exceptional growth marketeer, sharp storyteller, and a person with a vivid personality.
Pelagiya Dragomirova
Marketing Manager @ iO

Subscribe To My Brain Dump

Value-packed emails with no more than 600 characters.

I won't send you spam. Unsubscribe at any time.

Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.
Something's Unclear?

Frequently Asked Questions

Can I get a refund?
Yes. But only before submitting the questionnaire. Once I get your questionnaire responses I get to work and that's when you're not eligible for a refund.
What if I don't have any data yet?
You can purchase an additional Analytics Setup Add-On for 490 EUR. More details and link to purchase the Add-On will follow in the Kick-Off meeting.

If you do have analytics set up but not much data yet - that’s ok. This means that we have to focus on acquiring traffic and users to collect data to make further decisions.
I'm afraid I won’t see any progress and won’t have control over what you’re doing.
Experimenterra stands for 100% transparency. You will get regular updates on my progress. In the beginning, when there's the most work, you might even get daily updates. I ask for your feedback and approval before I launch anything to make sure you’re comfortable with anything I do (although sometimes I will push your comfort zone boundaries).
Why should I trust you?
I have nearly a decade of experience working with startups and founders. In my career, I’ve developed frameworks and processes that specifically fit early-stage startups. This means I approach your growth in a structural way so you understand the strategy and the outcome. Remember: your success is my success so I will go above and beyond to make you satisfied. My mantra is delivering value to the end user. This is what I preach to my clients and this is what I practice myself. I will treat your business as my own. I won’t do anything that I wouldn’t do for my own business. I give a detailed explanation and reasoning for everything I do and show you data to support my thinking.
What is the duration of the collaboration?
The Basic Package is typically delivered within 2 weeks. The Hands-On package takes more time and depends on the type of experiments I'm implementing. On average it takes up to 3 months to get enough data and gather insights to be able to report back to you.
By clicking “Accept”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. View our Privacy Policy for more information.