Should I use in-house or SaaS tools to develop APIs?

Many of today's software teams are faced with this question: Should you develop APIs with your own in-house tools, or use third-party SaaS API development tools? Ultimately, your choice probably won't impact the intended features or capabilities of the API -- it's just a matter of the preferred platform in which to write that API.

An API is an interface that allows external programs to use services an underlying application provides, but still shields the underlying application from outside users. Typically, developers don't develop APIs using the same language or format used in the associated application. For instance, many APIs operate over the internet by design. They employ a conventional HTTP series of GET, POST, PUT, DELETE and other HTTP methods based on languages such as Python.

It might make perfect sense to develop APIs on premises when the API can use existing software development toolchains, processes and staff. The additional costs and learning curves associated with outside API services may simply not be worth it.

However, there are compelling reasons to consider SaaS for API development. It's ideal to use an outside service when the API does not fit within the current software development toolchain. For example, suppose that a software team is set up with C++, Java IDEs and Selenium testing tools. That team might struggle to integrate another set of tools that write, test and manage Python-based APIs designed with Flask-RESTful and tested with tools like Postman or Insomnia. However, a SaaS provider could supply and maintain the toolchain instead.

Fortunately, the choice of on premises versus SaaS API development platforms is not an exclusive decision.

Similarly, an outside API development platform can be helpful if it provides features and functionality necessary for small, fast-evolving projects, like API creation. For example, APIs may demand a higher level of version control, style enforcement, documentation support or other features that current on-premises tools do not yet provide.

An outside API development service is also sometimes more cost-effective. If developers will use a particular toolchain only occasionally, it might not be worth the cost and effort to build it in-house. By comparison, you can use and pay for an outside API development platform on an as-needed basis -- effectively limiting the cost of deploying and maintaining additional tools.

Fortunately, the choice of on premises versus SaaS API development platforms is not an exclusive decision. Software teams can use existing on-premises tools for some API projects, but also rely on SaaS services as necessary for other projects.