Sadly I’m still having problems installing bonsai (bleeding edge version).
$ mkdir bonsai-switch; cd bonsai-switch
$ opam switch create . 4.11.2
$ opam repo add janestreet-bleeding-external https://github.com/janestreet/opam-repository.git#external-packages
$ opam repo add janestreet-bleeding https://ocaml.janestreet.com/opam-repository
$ opam update
$ opam install bonsai
(etc. etc)
#=== ERROR while compiling cohttp-async.4.0.0 =================================#
# context 2.1.0 | linux/x86_64 | ocaml-base-compiler.4.11.2 | https://opam.ocaml.org#f2f58c72
# path ~/bonsai-switch/_opam/.opam-switch/build/cohttp-async.4.0.0
# command ~/.opam/opam-init/hooks/sandbox.sh build dune build -p cohttp-async -j 7
# exit-code 1
# env-file ~/.opam/log/cohttp-async-1115039-13ff06.env
# output-file ~/.opam/log/cohttp-async-1115039-13ff06.out
### output ###
# Error: This expression has type [ `Use_Command_unix ]
# [...]
# (cd _build/default && /home/abcxyz/bonsai-switch/_opam/bin/ocamlc.opt -w -40 -g -bin-annot -I cohttp-async/bin/.cohttp_curl_async.eo
bjs/byte -I /home/abcxyz/bonsai-switch/_opam/lib/angstrom -I /home/abcxyz/bonsai-switch/_opam/lib/astring -I /home/abcxyz/bonsai-switch/_o
pam/lib/async -I /home/abcxyz/bonsai-switch/_opam/lib/async/async_command -I /home/abcxyz/bonsai-switch/_opam/lib/async/async_quickcheck
[...]
# File "cohttp-async/bin/cohttp_server_async.ml", line 129, characters 2-5:
# 129 | run
# ^^^
# Alert deprecated: Async_command.run
# [since 2021-03] Use [Command_unix]
# File "cohttp-async/bin/cohttp_server_async.ml", line 129, characters 2-5:
# 129 | run
# ^^^
# Error: This expression has type [ `Use_Command_unix ]
# but an expression was expected of type 'a -> 'b