CEEfarers - September 2025

Dear readers,

It’s been a while since our last newsletter, but rest assured, we haven’t been on a break – quite the opposite! We completed the first close of our fifth fund in June and have already made the first four investments. In addition, several of our portfolio companies raised exciting milestone rounds, and we hosted the largest engineering meetup in our history. Read on for the freshest news!

Roman Ondak. Exhibition at Peter Freeman Inc. “Waiting for Someone to Ring at My Door” New York. 9 September – 25 October 2025

⭐ New Investments

  • We’re excited to share that we’ve invested in Tom Krcha and his team, who just released pencil.dev – a design sidekick built right into your codebase and IDE. They’ve been building it as part of a16z Speedrun, making their recent launch even more exciting.
Design Mode for Cursor Introducing a new way to design right where you code. We call it Pencil and it's an MCP driven canvas built around open design files that live directly in your codebase and in… | Tom Krcha | 18 comments
Design Mode for Cursor Introducing a new way to design right where you code. We call it Pencil and it’s an MCP driven canvas built around open design files that live directly in your codebase and in your IDE, so all your AI agents can read them and write them. You can use it to just kick some ideas off or have it design full flows based on a design system. It’s your design sidekick that’s fully integrated into your codebase, so sharing and generating styles and components in the code has never been more seamless. It’s the end of design handoff and it doesn’t get any closer than this. Let me know if you want access, we’ll start inviting in batches soon and would love your feedback. | 18 comments on LinkedIn
  • Another exciting addition to our new fund is Mesmer – a startup founded by seasoned entrepreneurs on a mission to give CTOs clarity across the entire dev stack. João, Sergio, and Lucas, we’re thrilled to welcome you to the portfolio!
Today marks a new chapter for Mesmer (YC X25). We’re unveiling our product that is already changing the lives of engineering leaders at companies worth over $10B. We built Mesmer because as… | João de Paula | 64 comments
Today marks a new chapter for Mesmer (YC X25). We’re unveiling our product that is already changing the lives of engineering leaders at companies worth over $10B. We built Mesmer because as engineering teams scale, clarity disappears. Meetings multiply. Rituals pile up. Status updates replace real visibility. Mesmer brings that clarity back. It shows you what shipped, what slipped, and where to focus. Automatically, without process overhead. Engineering deserves to be run differently: faster, flatter, free of bureaucracy. Today, that future becomes real. Book a demo at mesmer.co. | 64 comments on LinkedIn
  • Two more companies still in stealth mode

  • If you’re shaping tomorrow’s breakthroughs, we want to hear from you. And if you know someone who is, tell us about them. 🙏 🚀

🚀 Follow-Ons

  • Jiří Třečák and the Supernova team just closed a $9.2M Series A. With the launch of Portal, their AI-driven product development platform, they’re set to expand into Asia and accelerate growth.
Czech Supernova Raises Series A to Bring Vibe-Coding to a Whole Product Team
Supernova, a Czech-founded company that entered Y Combinator in 2019 and evolved from a design-to-code tool into a full product development platform, has
  • After our pre-seed investment in TopK at the end of 2024, Marek Galovic and Jergus Lejko moved fast – iterating on their vector database search product and securing a total of $5.5M in seed funding.
The Perplexity for corporates? TopK lands $5.5M to build the next-gen AI-native search engine — TFN
TopK raises $5.5M to become the “Perplexity for corporates,” delivering next-gen AI-native search that unifies enterprise data for smarter results
  • Almost exactly a year after announcing their seed round, E2B has reached another major milestone. At the end of July, Vasek Mlejnsky and Tomas Valenta closed a $21M Series A, partnering with Insight Partners.
E2B Raises a $21M Series A to Offer Cloud for AI Agents to Fortune 100
SAN FRANCISCO, July 28, 2025 /PRNewswire/ — E2B, the leading provider of open-source cloud infrastructure specifically designed for AI agents, has raised a $21 million Series A funding round led by global software investor Insight Partners, with participation from Decibel, Sunflower Capital, and Kaya, along with prominent angels such as Docker’s former CEO Scott Johnston. The investment will enable E2B to […]
  • In addition, two more of our portfolio companies have successfully closed their Series A rounds, with announcements coming soon.

📰 Portfolio News

  • Juraj Masár recently sparked discussion on LinkedIn with his post about HardCore mode at Better Stack — a model where employees can choose to work extra hours for 2× salary. While it’s not for everyone, we believe there’s real value in this approach. It fairly rewards the extraordinary effort early employees often put into building startups, while offering those eager to push themselves and learn quickly an environment where they can thrive.
Hardcore mode™: opt-in to work 1.5x the hours, earn 2x the compensation Silicon Valley startups work “996”: 9am-9pm, 6 days a week. Chinese startups have been working like this for years. We think… | Juraj Masar | 39 comments
Hardcore mode™: opt-in to work 1.5x the hours, earn 2x the compensation Silicon Valley startups work “996”: 9am-9pm, 6 days a week. Chinese startups have been working like this for years. We think that’s unsustainable, but 60 hours per week can be, if you choose to opt-in. So we’re trying something new: when you’re joining Better Stack now you can choose if you want to work regular hours or 60 hours per week. If you opt-in to work 60 hours a week, reply to work messages on weekends, have 10 instead of 20 vacation days, 13 public holidays, and unlimited sick days, you’ll earn 2x the compensation of regular hours. It’s certainly not for everyone, but if you decide to go hardcore, you’ll learn and grow faster, tackle more interesting challenges, and experience the true early-stage startup experience. Please don’t get it twisted: we care about the results of your work. But inputs affects outputs. And reaching extraordinary results typically requires extraordinary effort. The companies you admire were built this way. And the best part? It’s not a long-term commitment. You can change your mind at the end of every month. | 39 comments on LinkedIn
  • Rohlik has decided to spin out a complete AI-enabled stack for other e-grocery companies in the form of a new venture, Veloq. Positioned at the intersection of retail and AI, Veloq aims to redefine how grocers run logistics, inventory, and customer experience at scale.
Czech Grocer Launches AI Delivery Platform to Rival Ocado
Czech online grocer Rohlik Group is spinning out its AI-driven platform for speedy grocery deliveries with worldwide ambitions, taking on the likes of Ocado Group Plc.
  • While in Prague, Vasek Mlejnsky gave an interview to Forbes where he shared his thoughts on startups and his plans for E2B.
Nechci do Microsoftu. Chci ho jako zákazníka, říká česká naděje v Silicon Valley
Americký technologický startup E2B vyvíjí mimořádně důležitou infrastrukturu pro AI agenty. A zatím nemá skoro žádnou konkurenci. Stojí za ním dva mladí Češi.

Czech language only


🕰️ Past Events

  • Pivko s klukama z Matfyzu vol. 8
    • What began as a small gathering of a few students in a pub has grown into one of the most established tech meetups in Prague. This time, we broke our own records again. Welcoming more than 400 engineers, students, founders, and scientists for an evening filled with tech talks, lively discussions, and plenty of food and drinks. A big thank you to our partners: Better Stack, TopK, Equilibre Technologies, Qminers, and Realpad for helping us make it all happen.
  • Built in Budapest
    • The same week, we hosted another engineering meetup in Budapest — our biggest event in Hungary so far. Together with Superlinked, Riptides, Portfolion, Seon, and Startup Hungary, we brought together 100+ engineers for an evening of engaging tech talks and lively discussions.

🔮 Future Events & Conferences

  • Prague Tech Soirée (21. 10.) — an invite-only event co-organized with Bek Ventures
  • Tech event in Warsaw — to be announced soon
  • How to Web — attending
  • Slush — attending

☺️ What made us smile

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Jamie Larson
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