Development within FLR is open to anybody, as source code is available, and suggestions, bug reports and code additions are welcome from any person. Package maintenance is the reponsability of their individual authors, who you can always find in the DESCRIPTION file inside every R package.
A number of people have taken responsability of different sections of the FLCore package, as their maintenance is of great importance for the whole of the FLR effort. These people are only taking the commitment of knowing well their section of code (usually one or two classes and their associated methods), and responding to any suggestion or bug report affecting them. They are also responsible for maintaining the test suite for their section of code, and ensuring tests are passed prior to release dates. At present, responsabilities are divided as follows:
Decisions on releases of the FLCore package are the responsability of the whole team, with Iago Mosqueira, Ernesto Jardim and Laurie Kell acting as release managers: compiling, final testing and uploading.
If you would to help out, you might start by looking at the 1 list and picking up a task that you find interesting or suited to your experience. Or you might find open issues being discussed in the mailing list and volunteer to solve one of them.