Observed Signal · Aug 25, 2026 · M&A - Announced · Source: Trending Topics · Impact: 2/5 · Sentiment: Neutral
Polish Callstack Acquires Vienna-Based React Native Firm Margelo
Polish software consultancy Callstack has acquired Vienna-based engineering firm Margelo in a transaction valuing Margelo at more than €20 million. Margelo is known for open-source React Native libraries such as Nitro Modules, VisionCamera, and react-native-mmkv, and lists Discord, Coinbase, Expensify, and VSCO as clients. Callstack, founded in 2016 in Wrocław, employs more than 200 people and serves over 100 enterprise customers. Margelo founder Marc Rousavy will remain on board and continue developing the libraries. The companies say AI is shifting software development toward architecture, performance, and secure releases. Callstack previously received a growth investment from Viking Global Investors in summer 2025, which valued the company at roughly €120 million. No closing date or regulatory approval details were disclosed.
Relevant tech M&A in React Native engineering; indirectly impacts mobile app and marketing technology infrastructure, with AI-driven development shift.
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Key Takeaways & Evidence Grounding
- Callstack is acquiring Margelo, valuing the Vienna-based firm at over €20 million.
- Margelo's open-source libraries include Nitro Modules, VisionCamera, and react-native-mmkv.
- Margelo has about 39 senior developers and lists Discord, Coinbase, Expensify, and VSCO as clients.
- Callstack was founded in 2016, employs more than 200 people, and serves over 100 enterprise customers.
- Viking Global Investors invested in Callstack in summer 2025, valuing it at about €120 million.
Connected Companies & Entities
8 Entities mapped“Der polnische Software-Spezialist Callstack übernimmt das Wiener Engineering-Unternehmen Margelo....”
“Der polnische Software-Spezialist Callstack übernimmt das Wiener Engineering-Unternehmen Margelo....”
“Als Referenzen nennt Margelo unter anderem Discord, Coinbase, Expensify, MetaMask, Rainbow, VSCO und WalletConnect....”
“Als Referenzen nennt Margelo unter anderem Discord, Coinbase, Expensify, MetaMask, Rainbow, VSCO und WalletConnect....”
“Als Referenzen nennt Margelo unter anderem Discord, Coinbase, Expensify, MetaMask, Rainbow, VSCO und WalletConnect....”
“Als Referenzen nennt Margelo unter anderem Discord, Coinbase, Expensify, MetaMask, Rainbow, VSCO und WalletConnect....”
“Damals stieg der US-Fonds Viking Global Investors mit einem Wachstumsinvestment ein, das Callstack laut eigener Aussendung mit rund einer ha...”
“Callstack wurde 2016 in Wrocław gegründet, wenige Monate nach der Veröffentlichung von React Native durch Meta....”
Ontology Mapping & Concepts
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