Keel's service based component architecture allows developers to plug the best components from any standards based open source library into their system and then upgrade to future components without having to rewrite the code base. Keel 2.0 provides a comprehensive environment for integrating Web applications, speeding development and establishing a consistent yet flexible base upon which to build systems.

Keel's component design allows new implementations to be added and old implementations replaced without extensive code rewrites. Services see each other as "black boxes" with clear boundaries that protect developers from being locked into a specific implementation environment. Keel evolved more quickly than most open source products because it makes use of pre-existing components not specifically built for Keel.

Installation of Keel 2.0 is now simplified. Version 2.0 also includes an automated build system that will compile the Java code and make deployment of completed Keel-based applications easier.

Keel 2.0 also offers improved data persistence. In Keel 1.0 there was one type of persistence available. In version 2.0 the persistence service has been decoupled from the core of Keel to give developers more options for tasks such as organization and storage. This adds a range of options to Keel's Default Persistence including relational databases, XML, and Hibernate.

Keel now utilizes Java Authentication and Authorization Service (JAAS) as its default security mechanism. Keel 2.0 can also make use of virtually any security architecture already in place, ensuring that systems can easily be customized and therefore are more difficult to successfully attack than COTS systems.

Keel is built on top of the Apache Avalon Project, and with it come three core concepts:

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