Reexported API

Each BoundaryValueDiffEq package exports a small, deliberate slice of the SciML common interface on top of its own solver algorithms, so that using BoundaryValueDiffEq (or using a single solver sublibrary) is enough to write the documented workflow without a second import line. None of these names are owned or documented here — this page says what each package forwards and who owns it, so you know where to go for the real documentation.

The lists below are kept in sync with the reexport export block in each package's src/<Package>.jl and with the approved allow-lists in test/qa/reexports.jl, which the QA suite checks on every run.

Owners linked from this page:

• SciMLBase — problem, function and solution types and the solve/init/remake interface.
• ADTypes — the Auto* automatic differentiation backend selectors.
• NonlinearSolveFirstOrder — the nonlinear solver algorithms accepted by every solver's nlsolve keyword.
• BoundaryValueDiffEqCore — the shared BVP configuration types, documented under Automatic Differentiation Backends, Error Control Adaptivity, Verbosity Control and Common Solver Options (Solve Keyword Arguments).

BoundaryValueDiffEq

using BoundaryValueDiffEq reexports the solver algorithms of every sublibrary (MIRK2–MIRK6, RadauIIa*, LobattoIII*, MIRKN4/MIRKN6, Ascher1–Ascher7, Shooting, MultipleShooting, plus maxsol/minsol and the ODEInterface wrappers), and in addition:

• AD backend selectors, from ADTypes: AutoEnzyme, AutoFiniteDiff, AutoForwardDiff, AutoMooncake, AutoPolyesterForwardDiff, AutoSparse
• Jacobian and verbosity configuration, from BoundaryValueDiffEqCore: BVPJacobianAlgorithm, BVPVerbosity, DEFAULT_VERBOSE
• Error control adaptivity, from BoundaryValueDiffEqCore: DefectControl, GlobalErrorControl, SequentialErrorControl, HybridErrorControl, NoErrorControl, HOErrorControl, REErrorControl
• Cost functionals, from BoundaryValueDiffEqCore: integral
• Problems, from SciMLBase: BVProblem, TwoPointBVProblem, SecondOrderBVProblem, TwoPointSecondOrderBVProblem, EnsembleProblem
• Functions, from SciMLBase: BVPFunction, DynamicalBVPFunction, ODEFunction
• Solving, from SciMLBase: solve, solve!, init, remake
• Ensemble algorithms for MultipleShooting, from SciMLBase: EnsembleSerial, EnsembleThreads
• Return status, from SciMLBase: ReturnCode, successful_retcode

BoundaryValueDiffEqMIRK and BoundaryValueDiffEqFIRK

In addition to MIRK2–MIRK6, MIRK6I, maxsol, minsol (MIRK) and the RadauIIa* / LobattoIII* algorithms (FIRK), both packages reexport:

• AD backend selectors, from ADTypes: AutoEnzyme, AutoFiniteDiff, AutoForwardDiff, AutoMooncake, AutoPolyesterForwardDiff, AutoSparse
• Configuration, from BoundaryValueDiffEqCore: BVPJacobianAlgorithm, BVPVerbosity, DEFAULT_VERBOSE, integral
• Error control adaptivity, from BoundaryValueDiffEqCore: DefectControl, GlobalErrorControl, SequentialErrorControl, HybridErrorControl, NoErrorControl, HOErrorControl, REErrorControl
• Inner nonlinear solvers for the nlsolve keyword, from NonlinearSolveFirstOrder: GaussNewton, LevenbergMarquardt, NewtonRaphson, TrustRegion
• Problems and functions, from SciMLBase: BVProblem, TwoPointBVProblem, EnsembleProblem, BVPFunction, ODEFunction
• Solving, from SciMLBase: solve, solve!, init, remake
• Return status, from SciMLBase: ReturnCode, successful_retcode

BoundaryValueDiffEqAscher

In addition to Ascher1–Ascher7, the same set as MIRK and FIRK, except that Ascher documents no ensemble workflow and so does not reexport EnsembleProblem or ODEFunction:

• AD backend selectors, from ADTypes: AutoEnzyme, AutoFiniteDiff, AutoForwardDiff, AutoMooncake, AutoPolyesterForwardDiff, AutoSparse
• Configuration, from BoundaryValueDiffEqCore: BVPJacobianAlgorithm, BVPVerbosity, DEFAULT_VERBOSE, integral
• Error control adaptivity, from BoundaryValueDiffEqCore: DefectControl, GlobalErrorControl, SequentialErrorControl, HybridErrorControl, NoErrorControl, HOErrorControl, REErrorControl
• Inner nonlinear solvers, from NonlinearSolveFirstOrder: GaussNewton, LevenbergMarquardt, NewtonRaphson, TrustRegion
• Problems and functions, from SciMLBase: BVProblem, TwoPointBVProblem, BVPFunction — the last of which carries the mass matrix for the semi-explicit BVDAE form Ascher solves
• Solving, from SciMLBase: solve, solve!, init, remake
• Return status, from SciMLBase: ReturnCode, successful_retcode

BoundaryValueDiffEqMIRKN

MIRKN solves second order boundary value problems, so it reexports the second order problem and function types rather than the first order ones, and — having no defect control adaptivity — only NoErrorControl from the error controllers:

• AD backend selectors, from ADTypes: AutoEnzyme, AutoFiniteDiff, AutoForwardDiff, AutoMooncake, AutoPolyesterForwardDiff, AutoSparse
• Configuration, from BoundaryValueDiffEqCore: BVPJacobianAlgorithm, BVPVerbosity, DEFAULT_VERBOSE, NoErrorControl, integral
• Inner nonlinear solvers, from NonlinearSolveFirstOrder: GaussNewton, LevenbergMarquardt, NewtonRaphson, TrustRegion
• Problems and functions, from SciMLBase: SecondOrderBVProblem, TwoPointSecondOrderBVProblem, DynamicalBVPFunction
• Solving, from SciMLBase: solve, solve!, init, remake
• Return status, from SciMLBase: ReturnCode, successful_retcode

BoundaryValueDiffEqShooting

Shooting reduces the BVP to initial value problems, so it reexports ODEProblem and the ensemble algorithms accepted by MultipleShooting's ensemblealg keyword. It is not a collocation method and takes no controller, so the error control types are not part of its surface:

• AD backend selectors, from ADTypes: AutoEnzyme, AutoFiniteDiff, AutoForwardDiff, AutoMooncake, AutoPolyesterForwardDiff, AutoSparse
• Configuration, from BoundaryValueDiffEqCore: BVPJacobianAlgorithm, BVPVerbosity, DEFAULT_VERBOSE, integral
• Inner nonlinear solvers, from NonlinearSolveFirstOrder: GaussNewton, LevenbergMarquardt, NewtonRaphson, TrustRegion
• Problems and functions, from SciMLBase: BVProblem, TwoPointBVProblem, ODEProblem, BVPFunction
• Ensemble algorithms, from SciMLBase: EnsembleSerial, EnsembleThreads
• Solving, from SciMLBase: solve, solve!, init, remake
• Return status, from SciMLBase: ReturnCode, successful_retcode

BoundaryValueDiffEqCore

Core is the shared base the solver sublibraries build on; it owns BVPJacobianAlgorithm, the error control types, BVPVerbosity, DEFAULT_VERBOSE and integral, and forwards:

• Nonlinear solvers, from NonlinearSolveFirstOrder: GaussNewton, LevenbergMarquardt, NewtonRaphson, TrustRegion
• Problems, from SciMLBase: BVProblem, TwoPointBVProblem, SecondOrderBVProblem, TwoPointSecondOrderBVProblem, NonlinearProblem, NonlinearLeastSquaresProblem, OptimizationProblem
• Functions, from SciMLBase: BVPFunction, DynamicalBVPFunction, NonlinearFunction, OptimizationFunction
• Solving, from SciMLBase: solve, init, remake
• Return status, from SciMLBase: ReturnCode, successful_retcode

Boundary

These lists are the whole of what these packages forward. Anything else from SciMLBase must be imported from SciMLBase directly, anything else from ADTypes from ADTypes, and anything else from NonlinearSolve from NonlinearSolve. In particular, solution types (ODESolution and friends), the integrator interface, callbacks and ensemble analysis are deliberately not reexported: BVP solvers return a solution object you index and interpolate rather than an integrator you step, so those names belong to their owners.