ApyHub Introduces Fusion, the Notion-like API Client

At ApyHub, we have built one of the largest API catalogs out there, dealing with hundreds of APIs every day. Something that we get asked a lot from our users and developers is how we handle all the building, testing, documenting & monitoring of these APIs. Quick answer: Not easily.

Main problems are rooted in:

Talking to our users, we realized that we were not the only ones living in this API nightmare.

So, we took action. Fusion is the result.

Isn't it strange? While IDEs and project management tools keep evolving and becoming better, API clients seem to be stuck in the past. Even the more recent and “modern” API clients seem to be “baked” using the same, very old ingredients:

We did not want to make one more API client like that. We did not even want to make an improved version of the existing API Clients, trying to improve bits and pieces of something that we believe needs a complete rethinking. Instead, we designed Fusion with the mantra to make developers forget everything they know about traditional API clients. We wanted to completely reimagine the API client as what we believe it has the potential to be: a real powerhouse tool for every modern developer and key enabler for every forward thinking development team.

Fusion was born in the era of Gen AI. Instead of tacking on some AI features here and there, we decided to weave them into the core of Fusion making it a seamless experience for developers. Fusion’s Gen AI capabilities help developers write, adjust, and perfect their API documentation based on feedback and real, to the point, suggestions.

Additionally, Fusion AI helps developers generate OpenAPI specs and implementation stubs from design documents. The AI keeps an eye on the API specs and documentation, alerting users when there are deviations and making relevant suggestions.

This way developers are always in the driver seat while the AI does all the heavy lifting.

Design First or Code First? The debate rages on. We get it; different teams have different needs. That’s why our idea with Fusion is to “Fuse” both approaches, creating a hybrid that eliminates the need to pick a side. Everything in Fusion is a “Fusion Doc” – a dynamic, functional document where the API testing client is also the API specs editor and the API documentation editor is the API testing tool. It’s not a gimmick. It’s a paradigm shift.

In Fusion, collaboration is more than a buzzword. We have seen with our own eyes how building in silos can lead to endless back-and-forths between frontend, backend, QA, and product teams. This is why one of the key pillars on which we designed Fusion is real-time collaboration. Our goal is to redefine the way people collaborate, by bringing everyone together on the same page instantly, viewing and discussing in real time the same API specs, tests and API documentation.

API testing has always been clunky, with tools carrying legacy baggage. Fusion changes the game with a fresh take on API testing. Every aspect of an API request is a “Fusion Block” – headers, query parameters, form inputs, JSON body, pre-request or post-request scripts. Everything is a block, and blocks are composable.

We wanted to make it very simple to create an API Spec or a Test Use Case within a Fusion Doc. For those who need to test a different scenario, Fusion allows users to create a new test that imports data from the original test case and overrides only the parts that need to change. This composability cuts down on writing and maintaining test cases by up to 60%. Yes, you read that right – 60%!

Developers are often both the victims and the perpetrators of bad API documentation. At the same time, technical writers are very often the victims of bad API design and of non-communicative developers - as it can be extremely difficult to document anything which one has not personally created.

To help bring some order in this vicious cycle, we designed Fusion in a way that would merge all the API specs, tests, and API documentation in one single place, making it suitable for both public and internal APIs, in house and client developers, technical writers or product managers.

How did we do that? Rather than creating more complexity, rules and roles, we decided to try something radical: Keep things simple and stay unopinionated. Everything created in Fusion is a “Fusion Doc.” And when we say “doc” we do not mean API documentation. We mean everything: From Tests, API documentation and API specs. Everything is a doc and everything is in one place.

Every Fusion Doc consists of different “Fusion blocks” (header, text, table, code, XML, JSON, query and so forth). This modularity of Fusion Blocks allows users to create a single source of truth that is always up-to-date. This way, the very idea of ownership (or lack thereof) disappears; the document is simply "live" – being dynamically updated as changes are made.

Need to share the API externally? Sure: Users can add specific instructions (in the same doc), provide examples, or just publish a generic API documentation. Fusion makes it effortless to keep everyone, from team members to clients, on the same page.

Fusion is a new kind of API client; A paradigm shift in API development and the way we think about APIs. Our vision is to break down functional and mental barriers of API management, simplify (inefficient and established) processes, and champion real collaboration.

Life is too short for clunky, outdated API management tools. Welcome to the future of API development. Welcome to Fusion.