opam 2.0.1 is out!

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We are pleased to announce the release of opam 2.0.1.

This new version contains mainly backported fixes, some platform-specific:

• Cold boot for MacOS/CentOS/Alpine
• Install checksum validation on MacOS
• Archive extraction for OpenBSD now defaults to using gtar
• Fix compilation of mccs on MacOS and Nix platforms
• Do not use GNU-sed specific features in the release Makefile, to fix build on OpenBSD/FreeBSD
• Cleaning to enable reproducible builds
• Update configure scripts

And some opam specific:

• git: fix git fetch by sha1 for git < 2.14
• linting: add test variable warning and empty description error
• upgrade: convert pinned but not installed opam files
• error reporting: more comprehensible error message for tar extraction, and upgrade of git-url compilers
• opam show: upgrade given local files
• list: as opam 2.0.0 list doesn't return non-zero code if list is empty, add --silent option for a silent output and returns 1 if list is empty

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Installation instructions (unchanged):

1. From binaries: run

sh <(curl -sL https://raw.githubusercontent.com/ocaml/opam/master/shell/install.sh)

or download manually from the Github "Releases" page to your PATH. In this case, don't forget to run opam init --reinit -ni to enable sandboxing if you had version 2.0.0~rc manually installed.

2. From source, using opam:

opam update; opam install opam-devel

(then copy the opam binary to your PATH as explained, and don't forget to run opam init --reinit -ni to enable sandboxing if you had version 2.0.0~rc manually installed)

3. From source, manually: see the instructions in the README.

We hope you enjoy this new major version, and remain open to bug reports and suggestions.

NOTE: this article is cross-posted on opam.ocaml.org and ocamlpro.com.

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About OCamlPro:

OCamlPro is a R&D lab founded in 2011, with the mission to help industrial users benefit from experts with a state-of-the-art knowledge of programming languages theory and practice.

• We provide audit, support, custom developer tools and training for both the most modern languages, such as Rust, Wasm and OCaml, and for legacy languages, such as COBOL or even home-made domain-specific languages;
• We design, create and implement software with great added-value for our clients. High complexity is not a problem for our PhD-level experts. For example, we helped the French Income Tax Administration re-adapt and improve their internally kept M language, we designed a DSL to model and express revenue streams in the Cinema Industry, codename Niagara, and we also developed the prototype of the Tezos proof-of-stake blockchain from 2014 to 2018.
• We have a long history of creating open-source projects, such as the Opam package manager, the LearnOCaml web platform, and contributing to other ones, such as the Flambda optimizing compiler, or the GnuCOBOL compiler.
• We are also experts of Formal Methods, developing tools such as our SMT Solver Alt-Ergo (check our Alt-Ergo Users' Club) and using them to prove safety or security properties of programs.

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