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DEVELOPMENT.md

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+# Developer Guidelines
+
+## General Rules
+
+1. Launch Pads support OpenStack Heat, Ansible, and OpenTofu.
+2. Launch Pads must behave substantially identically across all supported orchestration frameworks.
+3. Every configuration option must be available, and be named identically, across all supported orchestration frameworks.
+4. Every configuration option must be documented in the repository root README.
+
+### Exceptions
+
+* In a Launch Pad built with OpenStack Heat, the `pad_name` variable is replaced by the Heat stack name.
+
+## Supported versions
+
+* The OpenStack stack template supports the OpenStack Caracal, Epoxy, and Flamingo client libraries.
+* The Ansible playbooks support Ansible Core 2.16, 2.19, and 2.20, and the OpenStack Caracal, Epoxy, and Flamingo client SDKs.
+* The OpenTofu configuration supports OpenTofu 1.9, 1.10, and 1.11.
+
+## Style Guide
+
+* YAML files must conform to [yamllint](https://yamllint.readthedocs.io/).
+  See `.yamllint` for enabled rules.
+* Ansible playbooks must conform to [Ansible Lint](https://docs.ansible.com/projects/lint/) in a default configuration.
+* OpenTofu configurations must pass `tf validate` with any supported OpenTofu release.
+* Markdown files must use [one sentence per line](https://sive.rs/1s), and conform to [PyMarkdownLnt](https://pymarkdown.readthedocs.io/).
+  See `.pymarkdown.json` for enabled rules.
+
+## CI Pipeline
+
+This repo has both a GitLab CI pipeline definition (`.gitlab-ci.yml`) and GitHub Actions Workflows (in `.github/workflows`).
+
+The tests are substantially identical, and use parallel-build matrix strategies to cover the supported platforms.
+
+## Git Hooks
+
+`pre-commit`, `post-commit`, and `pre-push` hooks are available in `.githooks`.
+To enable, run this command:
+
+```shell
+git config core.hooksPath .githooks
+```