WunderGraph, a fledgling open-source startup, has secured $7.5 million in Series A funding to tackle API sprawl in the GraphQL ecosystem. The investment round was led by eBay Ventures, Karma Ventures, and Aspenwood Ventures, with eBay also serving as a core design partner. This partnership will enable WunderGraph to build an open-source alternative to rival GraphQL company Apollo's proprietary solution.

The startup, founded in 2020 by CTO Dustin Deus, CEO Jens Neuse, COO Björn Schwenzer, and CCO Stefan Avram, aims to provide a highly performant open-source platform to boost eBay's API ecosystem. According to Bryan Woodruff, eBay's VP of seller experience engineering, this investment will help eBay's teams work faster and smarter in building products that support its sellers.

For the uninitiated, GraphQL is a data query language for APIs that was developed at Meta (formerly Facebook) in 2012. It allows clients to request the exact data they need, making it more efficient compared to traditional REST APIs. However, as applications grow and the number of APIs increases, this can create an unwieldy mess that's difficult to orchestrate at scale.

WunderGraph initially built a software development kit (SDK) to unify multiple APIs, including GraphQL, REST, SOAP, and databases like MySQL. In 2023, the company raised a $3 million seed round to power the API revolution by building a "GitHub for APIs" – a platform for people to collaborate, share, and explore APIs. However, Apollo's decision to change its federation product from an open-source MIT license to a proprietary "source available" Elastic License created an opportunity for WunderGraph to fill the gap.

WunderGraph debuted Cosmo, an open-source alternative to Apollo Federation, in late 2023. As the core maintainer and contributor of its open-source effort, the company sells hosting and premium support and services, which might include help with integrating databases, analytics, authentication, and observability. Larger companies can build their own version of Cosmo in-house, but they would likely prefer to use WunderGraph's supported solution, backed by robust service-level agreements (SLAs).

The partnership with eBay has proven fruitful, with eBay providing direct design input to WunderGraph. This two-way process enables eBay to get the flexibility of an open-source GraphQL federation that suits its needs, while WunderGraph gains expertise in building a product that can be integrated into companies like eBay, which have specific requirements.

With the fresh $7.5 million in funding, WunderGraph plans to grow its 20-strong workforce and double down on its open-source GraphQL federation with additional tools that help distributed teams work more efficiently. The company believes that open source is the future of API management, and enterprises are demanding transparency, flexibility, and control.

WunderGraph's commitment to open-source development is expected to attract big-name customers that don't want to be locked into proprietary products. As the company scales, it's building the essential plumbing for the world's biggest platforms, and this funding allows it to do so while keeping its commitment to open-source development.