➜  reason git:(master) opam list
# Installed packages for 4.02.3:
base-bigarray                  base  Bigarray library distributed with the OCaml compiler
base-bytes                     base  Bytes library distributed with the OCaml compiler
base-ocamlbuild                base  OCamlbuild binary and libraries distributed with the OCaml com
base-threads                   base  Threads library distributed with the OCaml compiler
base-unix                      base  Unix library distributed with the OCaml compiler
biniou                        1.2.0  Binary data format designed for speed, safety, ease of use and
camomile                      0.8.7  A comprehensive Unicode library
conf-m4                           1  Virtual package relying on m4
conf-which                        1  Virtual package relying on which
cppo                          1.6.1  Equivalent of the C preprocessor for OCaml programs
easy-format                   1.3.1  High-level and functional interface to the Format module of th
jbuilder                 1.0+beta17  Fast, portable and opinionated build system
lambda-term                  1.12.0  Terminal manipulation library for OCaml
lwt                           3.2.1  Promises, concurrency, and parallelized I/O
lwt_react                     1.1.0  Helpers for using React with Lwt
menhir                     20171013  LR(1) parser generator
merlin                        2.5.4  Editor helper, provides completion, typing and source browsing
merlin-extend                   0.3  A protocol to provide custom frontend to Merlin
ocaml-migrate-parsetree       1.0.7  Convert OCaml parsetrees between different versions
ocamlbuild                        0  Build system distributed with the OCaml compiler since OCaml 3
ocamlfind                   1.7.3-1  A library manager for OCaml
ppx_tools_versioned             5.1  A variant of ppx_tools based on ocaml-migrate-parsetree
react                         1.2.1  Declarative events and signals for OCaml
result                          1.2  Compatibility Result module
topkg                         0.9.1  The transitory OCaml software packager
utop                          2.0.2  Universal toplevel for OCaml
yojson                        1.4.0  Yojson is an optimized parsing and printing library for the JS
zed                             1.6  Abstract engine for text edition in OCaml
➜  reason git:(master) opam pin add -y reason .
[NOTE] Package reason is already path-pinned to /home/andrea/Documents/reasonML/reason.
       This will erase any previous custom definition.
Proceed ? [Y/n] y

[reason] /home/andrea/Documents/reasonML/reason/ synchronized
[reason] Installing new package description from /home/andrea/Documents/reasonML/reason

reason needs to be installed.
The following actions will be performed:
  ∗  install reason 3.0.4*

=-=- Gathering sources =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
[reason.3.0.4] /home/andrea/Documents/reasonML/reason/ already up-to-date

=-=- Processing actions -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
∗  installed reason.3.0.4
Done.
➜  reason git:(master) refmt --version
Reason 3.0.0 @ bee43b0
➜  reason git:(master) ./_build/install/default/bin/refmt --version
Reason 3.0.0 @ bee43b0