add blog post about v1 recipe format

news/2025-02-13-conda-forge-v1-recipe-support.md

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+# Announcing the new recipe format on conda-forge
+
+The conda-forge team is excited to announce that the v1 recipe format is available on conda-forge. The v1 recipe format is a community initiative dating back over 3 years to improve the recipe format for conda packages. If you are a maintainer of a feedstock on conda-forge, you have probably dealt with `meta.yaml` files that conda-build utilizes. The file format has some limitations which is why the community has come together to come up with an improved version of the format: the v1 format.
+
+## rattler-build and the v1 spec
+
+The v1 recipe format has a number of benefits:
+
+- It always parses as valid YAML which makes it much easier to modify it with the bot infrastructure of conda-forge. While meta.yaml looks like YAML, it can contain Jinja logic incompatible with the YAML specification, which make significantly complicates parsing and automated manipulation. Additionally, the recipe has a published JSON schema which means that the editing experience in VSCode is greatly improved with contextual help.
+- The new recipe executes much faster, which is partially due to some design decisions (no more recursive evaluation) as well as due to rattler-build building on top of a modern re-implementation of the conda standards in Rust.
+- The log output of rattler-build is greatly improved, always showing the user what the final files in the package are and the final metadata.
+- Some features of conda-build, such as multiple outputs, had a lot of implicit behavior. We are fixing that in the v1 recipe.
+
+You can read much more about the v1 recipe format in the [https://rattler.build](https://rattler.build) docs and [CEPs](https://github.com/conda/ceps/).
+
+A simple v1 recipe looks something like the following:
+
+```yaml
+context:
+  # we define named variables in the context instead of `{$ set ... %}` directives
+  version: "23.0.0"
+
+package:
+  name: "boltons"
+  # note that we use "GitHub" inspired syntax to access context / Jinja variables
+  version: ${{ version }}
+
+source:
+  url: https://github.com/mahmoud/boltons/archive/refs/tags/${{ version }}.tar.gz
+  sha256: 9b2998cd9525ed472079c7dd90fbd216a887202e8729d5969d4f33878f0ff668
+
+build:
+  noarch: python
+  script:
+    - python -m pip install . --no-deps -vv
+
+requirements:
+  host:
+    - python
+    - pip
+    - setuptools
+  run:
+    - pip
+
+about:
+  license: BSD-3-Clause
+  license_file: LICENSE
+```
+
+## How to use the v1 recipe format on conda-forge
+
+If you are adding a new recipe on staged-recipes, then it's easy: just submit a `recipe.yaml` file instead of a `meta.yaml` file.
+In case you already maintain a feedstock, then the conversion can be semi-automated with a tool created by [Hadrien Mary](https://github.com/hadim) called ["feedrattler"](https://github.com/hadim/feedrattler). The tool will take care of the basic conversions steps and uses the `conda-recipe-manager` by Anaconda / Schuyler Martin under the hood to parse the recipe and convert it to the new format.
+
+```shell
+pixi exec feedrattler my-awesome-package-feedstock gh_user
+```
+
+To do the conversion by hand, you need to do the following things:
+
+- In the `conda-forge.yml`, add `conda_build_tool: rattler-build`
+- Remove the `meta.yaml` file and add a `recipe.yaml` file following the v1 spec
+- Rerender the feedstock using `conda smithy rerender`
+- Push your changes to your fork and open a PR to see the CI build your package
+
+## Transition plans
+
+For the foreseeable future, conda-forge is going to support both formats, v1 and v0. We envision a gradual transition over at least one year to the new spec. There are a couple of places where the v1 spec also needs to finalize / stabilize. One notable place is the `cache` output where CEP discussions are ongoing. This stabilization in the format should happen within Q1 of 2025.
+
+Since the beginning of 2025, the bot has gained more capabilities for the v1 format, such as automatically bumping versions (the "autotick-bot"). There are a number of other migrators and mini-migrators that need to be fully ported to the v1 spec before we can claim 100% compatibility with the conda-forge infrastructure.
+
+As of today, over 700 of the 25000 recipes on conda-forge have been converted.
+
+For now, the recommendation on staged-recipes is: if it's a simple `noarch: python` recipe, it should probably be a `v1` recipe. The same goes for `Rust` or `Go` projects that have a simple structure.
+
+### Where to learn more
+
+There are very helpful docs located at [https://rattler.build](https://rattler.build) that explain the differences of the new recipe format pretty well. You are also very welcome to chat with us on the [conda-forge Zulip](https://conda-forge.zulipchat.com/), or chat with the rattler-build developers on [their Discord](https://discord.gg/kKV8ZxyzY4).
+
+You can also read more about rattler-build and the v1 format in the following blog posts:
+
+- https://prefix.dev/blog/rattler_build_on_conda_forge
+- https://prefix.dev/blog/the_love_of_building_conda_packages
+- https://prefix.dev/blog/rattler_build_a_new_parser