The developer section is dedicated to people who are writing their own, new KNIME nodes. By design, KNIME was built to be extensible with novel functionality in the form of new nodes. Thus the API for KNIME nodes has been kept as simple as possible. We believe it should be possible to evaluate a new algorithm by quickly (and easily) crafting a new node. A more fully featured node with "extras" like a view, hilite support, fancy graphics, etc. can obviously consume as much time and effort as one is willing to spend, but the time it takes to quickly implement new ideas should be short and sweet.
To begin developing your own nodes, we offer these starting and reference points: