CHANGES:

• Some fixture for 5.3.0 @xvw
• Add Lattice @hakimba
• Add Bounded_lattice @hakimba
• Breaking change Move Monomorphized version of Result abstraction under the module Result.Mono and provide Indexed abstraction @mspwn
• Breaking change Remove manifest types in submodules (Infix and Syntax) @mspwn
• Add Indexed_functor, Indexed_alt, Indexed_apply, Indexed_applicative, Indexed_alternative, Indexed_selective, Indexed_bind, Indexed_monad, Indexed_monad_plus, Indexed_comonad, Indexed_foldable @mspwn, @gr-im, @xvw
• Add Bounded_join_semilattice @hakimba
• Add Bounded_meet_semilattice @hakimba
• Add Join_semilattice @hakimba
• Add Meet_semilattice @xvw and @hakimba
• Add Equivalence in Preface.Stdlib @gr-im, @xvw
• Add Preface.Laws and Preface.Qcheck to allow external users to build their own test suites for implementations outside Preface @gr-im, @xvw
• Breaking change change minimal version of OCaml to >= 4.12.0 @gr-im
• Exposition of Apply and Make in Preface.Make @gr-im

CHANGES:

• Add selective to Either, Options, Result and Try @d-plaindoux
• Add specialized interpreters/handlers for Free and Freer monads @xhtmlboi
• Add right-associative operators for Contravariant, Divisible and Decidable @xhtmlboi
• Add Bind @d-plaindoux
• Add Apply @d-plaindoux
• Add ('a, 'b) handle to simplify handlers for Freer_monad @xvw
• Rename times to times_to_nel for semigroup-ish and add times for monoid-ish @xvw
• Add Decidable (Contravariant analogue for Alternative) and add some missing infixes operators for Divisible @gr-im
• Removing early destructive substitution @xhtmlboi
• Add Semigroupoid @d-plaindoux
• Add Freer Selective @gr-im
• Add Invariant (Functor) (and some instance) @gr-im
• Add Kleisli and Cokleisli @gr-im
• Add Join, Joker and Clown @gr-im
• Relax constraint for definition of Profunctor and Choice using the Kleisli Arrow @gr-im
• Make List and Nonenmpty_list Traversable implementations (for both Applicative and Monad) Tail-recursive @xvw
• Add Seq module in Stdlib (with Functor, Applicative (with Traversable), Alternative, Monad (with Traversable), Monad_plus, Monoid and Foldable) @xvw
• Add mli for stdlib's test and example's test (in order to track unused tests) @xvw
• Use absolute URLs for image in documentation (in order to fit with the new version of OCaml.org) @xvw
• Add Selective for Free monad and Freer monad @xvw

CHANGES:

• First release (v0.1.0) by @d-plaindoux, @gr-im, @xhtmlboi and @xvw
• Esy support by @oteku
• Some patches on the documentation by @Sir4ur0n

And with the occasional but very valuable help of @snowleopard, @gasche, @Octachron, Oleg Kiselyov, Pierre-Evariste Dagand