During the API Strategy Conference panel discussion on Backend as a Service (BaaS), I was struck by the lack of clarity around BaaS market space boundaries and roadmaps.  While BaaS is currently well tuned for mobile client backend use cases, the market definition is on a collision course with Platform as a Service (PaaS).

PaaS offerings could easily extend and provide developer-friendly application platform services via consumable APIs; subsuming today’s BaaS value proposition.  As mobile application use cases collide with mission-critical enterprise requirements, developers will require more extensive platform capabilities, which are not delivered by BaaS today.   PaaS services deliver application platform capabilities required when building sophisticated applications.  For example, a BaaS offering billing, security, and data storage services today must evolve to offer messaging, registry, logging, and task management.  Figure 1 describes a few sample foundation services.  Additionally, leading PaaS environments offer application platform middleware services that span identity management, application lifecycle governance, integration, and custom code hosting (within app, service, process, rules, and data containers).

Figure 1.  Platform as a Service Reference Architecture and PaaS Services Layer

When the moderator, Kin Lane, asked the panel about their views regarding unique value proposition, a few participants mentioned ‘hosting custom code’.  My attention raised an order of magnitude!  Hosting custom code is the fundamental PaaS differentiator from IaaS (hosts servers) and SaaS (hosts configurations).

In a recent blog post, Toddy Mladenov brings an interesting perspective to the PaaS/BaaS value proposition:

 More than decade ago the application servers advanced the way new applications are developed by offering common framework and set of reusable components. Platforms-as-a-Service are the next step in the evolution of application development

As the underlying application platform evolves into PaaS, the innovator dilemma is unfolding and market disruption is occurring. The new school BaaS vendors are riding the mobile trend while delivering a useful toolbox for overcoming mobile application development hurdles.  Yet BaaS offerings are hitting a wall by offering a closed set of backend application services.  Innovative Public and Private PaaS vendors (e.g. Apprenda, Heroku, WSO2) are challenging established vendors (e.g. Oracle, IBM, Red Hat) as the preferred platform when forklifting web applications or building new cloud-aware applications.

As PaaS innovators focus on increasing application development agility, reducing time to market, and lowering backend skill hurdles, the line between PaaS Services and BaaS Services will blur.  The end goal is to deliver an open, extensible PaaS where developers can easily weave APIs, services, processes, data, and user interface widgets into a compelling user experience.