Web and graphical applications lend themselves to natural expression in an event-driven, dataflow style. This style is especially valuable when it layers reactivity transparently atop a traditional programming language. It has become especially necessary and valuable with the advent of Ajax applications, with events and flows both within and across processing nodes.
We have therefore built two languages, first FrTime ("father time") atop Scheme and now Flapjax atop JavaScript, to explore these ideas. We have studied implementation techniques, principles for interfacing to interface components and the network, applications such as scriptable debugging, program transformations to improve performance, and integration into programming environments. The talk will cover our results in these areas.