Local Usage

First Steps

opam-bin will take care automatically of generating binary packages and using them without supervision. The only thing you need to do is to configure opam to use opam-bin. This is usually done by:

opam-bin install

This command will do the following modifications:

Install a copy of opam-bin as ~/.opam/plugins/opam-bin/opam-bin.exe, and a link in ~/.opam/plugins/bin/opam-bin (so that opam bin also works)
Modify opam configuration files to call opam-bin everytime you install or remove a package. This is done by modifying the hooks in ~/.opam/config. For example:
```
post-install-commands:
[
  "/home/user/.opam/plugins/opam-bin/opam-bin.exe"
  "post-install" name version build-id depends installed-files
] {?build-id & error-code = 0}
```
Note that the command will remove sandboxing, so you think it shouldn’t, you will have to modify the files manually.
Add the local repository of binary packages:
- local-bin for file:///home/user/.opam/plugins/opam-bin/store/repo to be able to install binary packages on user request

After this step, opam-bin will create a binary package every time you compile a new source package, if and only if all the dependencies have also generated a binary package. It also means that you won’t get binary packages in a switch in which you have already installed packages without opam-bin installed.

Simple Example

Now that opam-bin is installed, let’s create a new switch that will generate binary packages:

opam switch create test-bin 4.07.1
opam install alt-ergo -y

We can check that binary packages have been created:

opam-bin list

gives the following output:

Binary packages in /home/user/.opam/plugins/opam-bin/store/archives:
alt-ergo.2.3.2+bin+e36313ee+a8034f9e-bin.tar.gz
alt-ergo-lib.2.3.2+bin+c8fa4342+e81dc009-bin.tar.gz
alt-ergo-parsers.2.3.2+bin+716cf20e+b265b234-bin.tar.gz
base-bigarray.base+bin+4d1fcc87+f2cc4984-bin.tar.gz
base-threads.base+bin+fab854ad+f2cc4984-bin.tar.gz
base-unix.base+bin+9223113a+f2cc4984-bin.tar.gz
camlzip.1.10+bin+f6025bac+28b615e5-bin.tar.gz
conf-autoconf.0.1+bin+42ea19bc+f2cc4984-bin.tar.gz
conf-gmp.1+bin+cfddfccd+f2cc4984-bin.tar.gz
conf-m4.1+bin+67ca415f+f2cc4984-bin.tar.gz
conf-perl.1+bin+b7a00120+f2cc4984-bin.tar.gz
conf-pkg-config.1.2+bin+3ae7fa61+f2cc4984-bin.tar.gz
conf-which.1+bin+8abe2442+f2cc4984-bin.tar.gz
conf-zlib.1+bin+55cf1879+f2cc4984-bin.tar.gz
dune.2.6.1+bin+8e4c5a68+17b54c37-bin.tar.gz
menhir.20181113+bin+1dcc3ac1+cb11610e-bin.tar.gz
num.1.3+bin+e6840903+a31a8afc-bin.tar.gz
ocaml.4.07.1+bin+b6e07913+f2cc4984-bin.tar.gz
ocaml-base-compiler.4.07.1+bin+9dc450ca+237a0dc7-bin.tar.gz
ocamlbuild.0.12.0+bin+dbf59d87+8ab32167-bin.tar.gz
ocaml-config.1+bin+560cba57+06f6b799-bin.tar.gz
ocamlfind.1.8.1+bin+4e9e0eee+d53044bc-bin.tar.gz
ocplib-simplex.0.4+bin+2e969ade+dad7e6b6-bin.tar.gz
psmt2-frontend.0.2+bin+e8598f63+5327c084-bin.tar.gz
seq.base+bin+90db3692+17bae418-bin.tar.gz
stdlib-shims.0.1.0+bin+b219c1e7+97629a4c-bin.tar.gz
zarith.1.9.1+bin+e25c81d3+f97da984-bin.tar.gz

Let’s retry in another switch, to check if opam-bin correctly install the binary packages:

$ opam update
$ opam switch list-available
ocaml-base-compiler 4.07.1+bin+9dc450ca+237a0dc7
$ opam switch create test-reloc 4.07.1+bin+9dc450ca+237a0dc7
$ opam install alt-ergo+bin -y

Another solution is to start from an empty switch:

$ opam switch create test-reloc --empty
$ opam install alt-ergo+bin -y

We can also search in the generated binary archives for specific files:

opam-bin search bin/alt-ergo

and the output is:

alt-ergo.2.3.2+bin+b7812268+ea4c83e2:file:009664912:reg:bin/alt-ergo

Basic Configuration

Let’s have a look have the configuration of opam-bin:

opam-bin config

outputs something like:

Current options (from /home/user/.opam/plugins/opam-bin/config):
  base_url : /change-this-option
  rsync_url : None
  patches_url : git@github.com:OCamlPro/relocation-patches
  enabled : true
  create_enabled : true
  all_switches : true
  version : 1
  switches :
  protected_switches :

We will not discuss the first 2 options that are only useful if you plan to share the binary packages that you generate. Instead, we can look at the other options.

patches_url is the URL to the git repository containing patches to make packages relocatable. It is used when you call opam-bin install or opam-bin install patches. For example, if you want to use a local copy of this repository, you can modify it for later use:

git clone git@github.com:OCamlPro/relocation-patches
cd relocation-patches
opam-bin config --patches-url file://$(pwd)
opam-bin install patches

The next options are used to enable/disable opam-bin globally (enable) and to enable/disable creation of binary packages from source packages (enable_create). For example, if you want to create cached binary archives for the dependencies of a package but not for the package itself:

opam-bin config --enable-create
opam install --deps-only coq
opam-bin config --disable-create
opam install coq
opam-bin config --enable-create

Finally, it is possible to control on which switches opam-bin will be enabled:

opam-bin config --protected-switches '-,4.07.1-src,*+src'

This will tell opam-bin to disable binary packages for switch 4.07.1-src and all switches matching the regexp *+src.

It is also possible to disable opam-bin for all switches except some of them:

opam-bin config --not-all-switches --switches '-,*+bin'