In the world of software, users judge apps by how they look and feel. In the world of software development, developers pass judgement on the quality of an API by its documentation. By definition an API doesn’t have a user interface, so at first glance, the documentation is the user experience. It’s just that the users of APIs are software developers.

Recently Mailchimp approached Postlight and asked for help. They offered developers two powerful, heavily-used public APIs: Mandrill and the Mailchimp API. But the two APIs lived on different websites, had different types of documentation associated with them, looked and felt like they were from different planets, and in the case of Mandrill, appeared to be neither maintained nor updated for over four years. Usage was slowing, competitor products were wooing developers away, trust was eroding, and there was a gap in the tools and libraries available to developers to interact with the products.

Postlight’s mandate was clear: To unify Mailchimp’s programmatic products in a single place, provide a best-in-class developer experience through documentation and tooling, and in the process, establish Mailchimp as a modern, world-class technology company.

The results of our partnership just went live at https://mailchimp.com/developer. The all-new Mailchimp Developer features:

• A fresh new dark mode-inspired look and feel
• Rebranded APIs that live side-by-side: the Marketing API (formerly Mailchimp) and the Transactional API (formerly Mandrill)
• A completely redesigned and unified, state-of-the-art API Reference, featuring choose-your-language interactive code snippets
• New client libraries in multiple programming languages for both APIs, distributed via package managers everywhere
• Rewritten and refreshed Developer Guides that walk developers through how to accomplish specific tasks with each API, step by step
• An all-new Release Notes area and Engineering Blog
• A mobile experience optimized for developers looking up answers or troubleshooting on the go
• A developer-specific search function that makes it easy for developers to find what they need

Alongside the launch, Mailchimp pledged $1M to developers building integrations with their APIs to service small and medium-sized businesses hit hard by COVID.

A Place by Developers, for Developers

We began this effort by talking to users. Our product design team interviewed dozens of developers, marketers, developers who work with marketers, and marketers who work with developers. From those discussions, a key insight guided the rest of the effort: Developers don’t want to be marketed to. They’re smart, busy professionals on a deadline who want the info they need, no more and no less, to help them build working software.

Mailchimp Developer had to be a place that was welcoming, familiar, and it had to speak to developers in their language. This premise guided every visual and user experience choice as well as our Mailchimp Developer content strategy. 

We heard (and knew from our own experience) that you need to go where developers already are. As part of this launch, Mailchimp published their API specs in a public repository on GitHub. This means that throughout Mailchimp Developer, developers see “Improve our docs on GitHub” links that encourage them to contribute back suggestions and clarifications to documentation, in a virtuous cycle of collaboration.

Tools in Every Language

We knew that being able to get started quickly with the APIs was paramount to adoption–in every developer’s programming language of choice. The API Reference features working code snippets in the most-used languages, from PHP to Node.js to Ruby, Python, and cURL.

Mailchimp and Postlight engineering also built and shipped all-new SDKs in four languages for both APIs, which are now public code in the Mailchimp GitHub organization and distributed via package managers everywhere.

Like the API Reference, those SDKs are auto-generated from the API specification. When the spec changes, the API Reference and all the SDKs are rebuilt and published automatically via GitHub Actions. This ensures the tools and documentation are always reliably aligned and up-to-date. Leveraging code generation tools also make introducing and maintaining SDKs in additional languages easier in the future.

Mailchimp’s suite of marketing products enable great brands to communicate with their customers and users (including Postlight’s newsletter!). Now developers have the documentation and tools they need to enable more businesses to serve their customers with custom integrations and apps. Take a look at the new Mailchimp Developer, and let us know what you think.

Gina Trapani (@ginatrapani) is a Managing Partner at Postlight. Want to talk about developer user experience? Get in touch: hello@postlight.com.