V26.14:show hn: petal, open-source coscreen/screenhero finally free

Overview

Petal addresses a genuine and acute pain point: the repeated cycle of acquiring beloved pair-programming tools (Screenhero → Slack, Wasabi → Miro, Multi → OpenAI) and killing them. This has created genuine trust deficit in the market. A free, open-source, community-governed alternative directly solves this.

The team is well-positioned — four former CoScreen engineers with deep domain expertise who built the MVP in under eight weeks using frontier AI models. They have instant credibility with the target audience (developers, engineering leads, open-source adopters). The "persistent rooms" feature and zero-config hosted option reduce friction significantly compared to alternatives. The open-source positioning also naturally drives community contributions and adoption, creating network effects.

Score Breakdown

What They Do

Hi HN! I’m Jason Thomas, one of the founders of CoScreen. As some of you may know, Datadog sunset the CoScreen service on July 31st. Four of us from the original CoScreen team have spent the last couple months building a free and open source pair programming tool inspired by those that came before us: It’s called Petal ( https://github.com/kiruna-labs/petal ) Some history first, because when we started CoScreen we had hoped to break the sad and established pattern of this industry. Screenhero was an exceptional tool that a lot of us loved for pairing. Multiple cursors, low latency, you could click your partner’s editor, and just start typing. It felt like magic while we had it. Then Slack bought it in 2015, and shut down the standalone app in December 2017. When Till, Max, and I started CoScreen, we were aware of this history, and wanted to build an even more magical collaboration and screen sharing experience: the entire concept was “throw a window from your laptop up on someone else’s screen, and start collaborating with zero friction.” Datadog acquired us in 2022, and thus began the great adventure of adapting our real-time technology into Datadog products, while also continue developing CoScreen as a standalone tool from the Datadog ecosystem. Datadog invested in the product for years and we’re thankful for that. But CoScreen itself proved, like so many other screen sharing tool acquisitions, to be too tangential from the customer base and core mission. We instead built other communication features in Datadog, the integrations with other video platforms, and also its wildly successful MCP server. We weren't the only ones. Around was bought by Miro and shut down in March 2025. Multi (formerly Remotion) was acqui-hired by OpenAI in 2024 and shut down about a month later. It's nearly always the same story: a small team builds something hard that people love, a platform buys it for the team or the feature, and the standalone product doesn't survive the integration. So we decided firmly to do things differently this time. Petal is completely free and open source and we aren't monetizing it. If we lose interest or get hit by a bus, you can self-host it or fork it, and nobody can sunset it on you. Honestly it's a love letter to everyone in this community that supported us, believed in us, and to liberate collaborative screen sharing from this vicious cycle. We hope through this we can help foster a large and vibrant community around innovating in this product sector. What Petal does: shared windows show up as real windows on your desktop, movable and resizable, not tiles in a grid. Several people can share at once, everyone gets a labeled cursor, and you can click into any shared window to type and scroll. Rooms are persistent, so you click once to join "eng-sync" instead of passing links around. It runs on macOS and Windows (Linux is next, this time for real and you can help us!), plus a web app. Media goes over LiveKit. You can use our hosted instance with zero config, or point the app at your own LiveKit server with one docker-compose if you want the traffic to stay on your network or even use an entirely different video backend if you want to. The part that still feels strange to us: CoScreen took almost six years to build. The first version of Petal took under eight weeks, from scratch, with frontier models like Fable and Astra doing a lot of the work. Real-time video and window capture is some of the most unforgiving code we have ever written, so we didn't expect that. We will do a proper writeup on what worked and what didn't, and are happy to answer questions about it here. Till, Darren, Max and I will be in the thread.

Why It Matters

Business Model

To be determined based on project analysis.

CRP Decision Report

🧠 Advisor

[score: 8]

[score: 8.0]

🧨 Devil

No monetization / no business model: Even open-source projects need resources. If the four founders lose interest, burn out, or face financial pressure, the project becomes exactly what they're trying to escape — subject to whatever whim the current maintainers have. There's no governance structure, funding mechanism, or sustainability plan described.
Zero defensibility: Anyone can fork this tomorrow. Not a technical concern, but a strategic one — there's no moat, no brand loyalty built yet, no revenue to fund improvements. Competing with existing free options (Zoom screen share, VS Code Live Share, Obsidian, etc.) that are already integrated into developers' workflows.
Post-acquisition trauma as both opportunity and trap: The emotional pitch resonates, but it also limits the TAM. Developers are increasingly satisfied with free built-in tools (VS Code Live Share is deeply integrated, Zoom/Slack have decent sharing). Convincing people to install and trust a new application is hard.
Technical complexity underestimation: They note real-time video/window capture is "some of the most unforgiving code" they've written. Cross-platform support (macOS, Windows, Linux, web) on top of that is a significant maintenance burden. LiveKit dependency adds another layer of external risk.

[score: -6]

[score: -6.0]

📚 Historian

Screenhero (acquired by Slack 2015, killed 2017), Wasabi (acquired by Miro, killed 2025), Multi (acquired by OpenAI, killed 2024), and CoScreen (acquired by Datadog, killed 2026) form a clear pattern: acquisition → integration → death. The market signal is strong — there was demand large enough for big players to acquire, but too tangential to core products to preserve.

However, open-source alternatives have survived and thrived where proprietary tools died: Blender replaced softwares that got killed, Godot fills gaps left by Unity pricing changes, OBS outlasted proprietary screen recorders. The open-source survival rate for beloved dev tools is significantly better than the proprietary acquisition route.

The historical counter-pattern: Chrome Remote Desktop, VS Code Live Share, and even standard Zoom screen sharing have captured the low-cost/free segment. These aren't doing badly. Petal needs to differentiate beyond "we're not going to be killed."

[score: 5]

[score: 5.0]

🧮 Budget Steward

From zero to first paying customer (or first meaningful contributor/volunteer), this project is already partially built. Let's assess incremental costs:

**Development (existing codebase, AI-assisted)**: Already done (0 marginal). Continued development by 4-person team — mostly opportunity cost, not cash. If outsourced to maintain cross-platform parity: ~8,000–12,000 for a contractor to polish and maintain.
**Infrastructure (hosted instance for petal.live)**: LiveKit cloud or self-hosted. Self-hosted via docker-compose is essentially free; managed LiveKit starts at ~50–200/month. Budgeting 3 months: ~600.
Third-party services: Domain, basic CI/CD, optional hosting: ~$200.
Legal/compliance: Open-source license (MIT assumed), no complex compliance. Basic legal templates: ~$500.
**Developer accounts, payment processing (if they ever monetize)**: ~$200.
Security audit: If they want to reassure users about a tool that controls screen/window access — $2,000–5,000. Recommended but not urgent.

Total estimated cost: $1,500–2,500 for a reasonable path to a maintained, secure, community-ready project.

This is extremely lean. Even with a buffer, well under $15,000. The funding gap is negative (well within budget). [score: +1]

🧱 Founder

Yes, build this — and we should do it the way they're doing it: open-source, free, community-driven. The ask isn't "spend money to build," it's "protect and nurture."

How: Fork from their existing codebase (already done). Contribute fixes, help with Linux support, propose governance structure. Consider a lightweight funding model (GitHub Sponsors, Tidelift) to compensate maintainers without compromising openness.

Timeline: Community-driven — 3–6 months to reach critical mass of contributors and stable Linux support. The hosted version is immediately usable; self-hosting is plug-and-play. No product-market fit risk since the problem is proven and the team has track record.

Risks to watch: Sustainability beyond the founding four. I'd advocate for establishing a foundation or stewardship model early to avoid the very fate they're escaping.

Verdict: Strong yes on the open-source front. If considering a commercial wrapper or hosted premium tier, proceed cautiously — the community built this on anti-monetization trust. [score: 7]

[score: 7.0]

Why This Made Only 10

This project was selected because it scored highly across our evaluation framework. The CRP analysis confirmed strong potential, making it one of the most promising opportunities this week.