So you're looking to help out DifferentialEquations.jl? We'd be happy to have your help. It is recommended you first discuss with some of the developers on the Gitter channel to make sure that you're up-to-date with current developments.
The Common Interface
The DiffEq ecosystem is built around the common interface. This is the interface for the solvers:
and the standard methods for dealing with solutions. Ecosystem builds problem types for solvers to act on, and add-on components which use the solution types for higher-level analysis like parameter estimation and sensitivity analysis.
One can add components at any of these levels to improve the functionality of the system as a whole.
JuliaDiffEq is setup in a distributed manner to allow developers to retain authoritative control and licensing for their own packages/algorithms, yet contribute to the greater ecosystem. This gives a way for researchers to target a wide audience of users, but not have to fully contribute to public packages or be restricted in licensing. At the center of the ecosystem is DiffEqBase which holds the
Algorithm types (the algorithms are defined in DiffEqBase to be accessible by the
default_algorithm function. One can opt out of this). Then there's the component solvers, which includes the
*DiffEq packages (OrdinaryDiffEq, StochasticDiffEq, etc.) which implement different methods for
solve. Then there are the add-on packages, such as the
DiffEq* packages (DiffEqParamEstim, DiffEqDevTools) which add functionality to the
solve setup. Lastly, there's DifferentialEquations.jl which is a metapackage which holds all of these pieces together as one cohesive unit.
If one wants their package to officially join the ecosystem, it will need to be moved to the JuliaDiffEq organization so that maintenance can occur (but the core algorithms will only be managed by the package owners themselves). The
Algorithm types can then be moved to
DiffEqBase, and after testing the package will be added to the list packages exported by DifferentialEquations.jl and the corresponding documentation.