In an earlier posting, we looked at some of the attributes that enable a product to serve as a successful platform for hosting third party applications. Specifically, we looked in some detail at two of the six factors that govern a platform's acceptance: predictability in terms of release cycle, and reliability in matters of application compatibility across multiple deployed releases of a platform. In this second installment, we'll examine in some detail four other qualities that successful platforms share.

First, it's important that a platform be usable. This means primarily that it presents relevant concepts in a manner that is familiar to the target audience. For example, a system that is intended for use in a Microsoft .NET environment should probably express its public object model in terms of methods, properties, and events. Documentation for these APIs should adhere to all the standard conventions a target user would find in the native system documentation. A strong emphasis on complete an technically accurate functional descriptions, robust sample suites, and a library of code "snippets" all support the usability of a platform by external developers. Metrics that help assess the success of these efforts include the rate of platform adoption over time, and the level of involvement required by the technical support staff.

Second, the facilities exposed by the platform should be useful. Creating a truly effective platform involves a fair amount of market research and competitive analysis to determine what types of applications external developers want to create. If the goal of the platform APIs is to provide integration with existing systems, for example, make sure that enough use cases have been defined and successfully implemented to give some assurance that the coverage is sufficient. The extent to which a platform provides truly useful capabilities can be measured by both the platform adoption rate, and by the diversity of deployed solutions.

Next, successful platforms are sustainable. Cross-release application compatibility is critical, and may be at odds with the development organization's goals for evolving the underlying codebase. Ideally, applications or extensions built on the platform will continue to function without change across new versions platform releases. To the extent that there are underlying changes that might affect existing applications, a strong communication channel to the developer community through forums, wikis, etc. is essential.

Finally, the best platforms are extensible. In addition to providing facilities on which compelling applications can be built, their underlying architecture allows the set of services itself to be extended by outside developers. This can lead to a rich ecosystem for your product in which the set of available capabilities need not be limited by the development capacity of your internal staff.

Part of the role of a product manager responsible for a system that can serve as a platform involves working with a number of different functional organizations to define an effective product and roadmap. The six platform criteria noted in these two postings can help provide a framework for these discussions. Be sure, for example, that the team responsible for overall platform architecture understands the goal of establishing a third-party eco-system around your product, and that the software is developed with an eye toward extensibility and cross-release compatibility. Similarly, stress the importance of compete API documentation and a robust suite of samples when working with those responsible for technical publications. The table below illustrates some typical organizational functions and how they might influence each of the six success criteria.