Vespa adds .NET support through Outmatic's open-source Vespa.Net

Vespa.ai has added .NET support for its open-source search platform through Vespa.Net, a client built and maintained by Outmatic. The move opens Vespa’s hybrid retrieval, ranking and real-time serving tools to enterprise .NET teams that want to build AI search and agentic applications without changing stacks.

Why it matters: - .NET is a major enterprise development ecosystem, and the new support lowers the barrier for Microsoft-centered organizations to use Vespa OSS. - Enterprise and mid-market teams can build vector search, hybrid retrieval, machine-learned ranking, recommendations, conversational AI and AI agents while keeping existing .NET skills and operational practices. - Vespa.Net removes the need for many teams to build a custom integration layer or add another language to their application stack.

What happened: - Vespa.ai announced .NET support for Vespa through Vespa.Net, an open-source client developed and maintained by Outmatic. - The announcement was made July 28, 2026, in Trondheim, Norway. - Outmatic specializes in AI-powered search and applied AI with a strong focus on the .NET ecosystem.

The details: - Vespa.Net provides a purpose-built interface between .NET applications and Vespa OSS. - The client lets .NET teams integrate Vespa directly into existing applications and development workflows. - Vespa.ai said the release brings Vespa OSS to one of the world’s largest enterprise developer ecosystems. - Organizations can use Vespa’s retrieval, ranking, machine learning and real-time serving capabilities from .NET. - Jon Bratseth, CEO of Vespa.ai, said millions of developers use .NET for business-critical enterprise applications and have historically had fewer options for advanced, large-scale AI search. - Alessandro Petrelli, Chairman and Founder of Outmatic, said Vespa.Net was first built for Outmatic’s own client projects and released openly because access to search infrastructure should not depend on programming language. - Under the partnership, Outmatic will continue developing and maintaining Vespa.Net as an open-source project. - Outmatic will also provide implementation and engineering services for organizations building Vespa-based applications in .NET. - Vespa.ai said the platform supports high-performance AI search, recommendations, conversational AI and AI agents on a single platform. - Vespa says its platform combines retrieval, ranking, machine learning inference and real-time serving to deliver high relevance, predictable latency and massive scalability. - Vespa.ai says companies including Yahoo, Spotify, Perplexity and AlphaSense use the platform.

Between the lines: - The partnership gives Vespa a cleaner path into enterprises that have standardized on Microsoft tooling. - Outmatic is positioning Vespa.Net as both a technical bridge and a services entry point for production deployments. - The release also signals growing demand for AI search infrastructure that fits inside existing enterprise stacks instead of forcing a platform rewrite.

What's next: - Outmatic will keep expanding and supporting Vespa.Net as an open-source project. - Outmatic will work with organizations that want implementation help for .NET-based Vespa applications. - More enterprise teams may test Vespa OSS now that .NET integration is available without major stack changes.

The bottom line: - Vespa’s .NET support makes its AI search platform more accessible to enterprise teams that want advanced retrieval and ranking without leaving the Microsoft ecosystem.