Added AI instructions.

Author: AlexSkrypnyk

CLAUDE.md

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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This project provides a MariaDB Docker image for Drupal that captures database data as Docker layers. Unlike traditional MariaDB containers that use volumes, this image stores database files in a non-volume location (`/home/db-data`) allowing the entire database to be captured, stored, and distributed as a Docker image.
+
+**Key Innovation**: Database files are stored as Docker layers rather than volumes, enabling instant database availability without time-consuming imports.
+
+## Architecture
+
+### Core Components
+
+1. **Dockerfile** - Extends `uselagoon/mariadb-10.11-drupal` base image:
+   - Sets custom data directory via `MARIADB_DATA_DIR=/home/db-data` (not a volume)
+   - Replaces entrypoint script to support custom data directory
+   - Overrides CMD to use `--datadir=/home/db-data`
+
+2. **entrypoint.bash** - Modified from [upstream](https://github.com/uselagoon/lagoon-images/blob/main/images/mariadb/entrypoints/9999-mariadb-init.bash):
+   - Supports `MARIADB_DATA_DIR` environment variable
+   - Handles database initialization in custom location
+   - Supports `MARIADB_COPY_DATA_DIR_SOURCE` for pre-filling data
+   - Includes `FORCE_MYSQL_UPGRADE` flag for forcing upgrades
+
+3. **seed.sh** - Three-phase database seeding script:
+   - **Phase 1**: Import SQL dump into temporary container and extract database files
+   - **Phase 2**: Build new image with extracted database files using `docker buildx`
+   - **Phase 3**: Verify database exists in the new image
+   - Supports multi-platform builds (linux/amd64, linux/arm64)
+   - Uses `docker buildx` to push directly to registry during build
+
+### Important Patterns
+
+- Database files must be in `/home/db-data` (not `/var/lib/mysql`)
+- Upstream base image version follows [uselagoon/mariadb-drupal tags](https://hub.docker.com/r/uselagoon/mariadb-drupal/tags)
+- The entrypoint script is minimally modified for easy upstream updates
+- Containers typically run as user `1000` (not `mysql`) in production
+
+## Development Commands
+
+### Testing
+
+Run all BATS tests:
+```bash
+npm --prefix tests/bats ci
+tests/bats/node_modules/.bin/bats tests/bats
+```
+
+Run specific BATS test file:
+```bash
+tests/bats/node_modules/.bin/bats tests/bats/image.bats --tap
+tests/bats/node_modules/.bin/bats tests/bats/seed.bats --tap
+```
+
+Run Goss tests (structural tests):
+```bash
+docker build -t testorg/testimage:test-tag .
+GOSS_FILES_PATH=tests/dgoss dgoss run -i testorg/testimage:test-tag
+```
+
+### Linting
+
+Lint shell scripts:
+```bash
+shfmt -i 2 -ci -s -d seed.sh tests/bats/*.bash tests/bats/*.bats
+shellcheck seed.sh tests/bats/*.bash tests/bats/*.bats
+```
+
+### Building and Seeding
+
+Build image locally:
+```bash
+docker build -t drevops/mariadb-drupal-data:local .
+```
+
+Seed image with database (single platform):
+```bash
+./seed.sh path/to/db.sql myorg/myimage:latest
+```
+
+Seed image with database (multi-platform):
+```bash
+DESTINATION_PLATFORMS=linux/amd64,linux/arm64 ./seed.sh path/to/db.sql myorg/myimage:latest
+```
+
+Use custom base image:
+```bash
+BASE_IMAGE=drevops/mariadb-drupal-data:canary ./seed.sh path/to/db.sql myorg/myimage:latest
+```
+
+### Platform-specific Testing
+
+Test for ARM64:
+```bash
+BUILDX_PLATFORMS=linux/arm64 DOCKER_DEFAULT_PLATFORM=linux/arm64 tests/bats/node_modules/.bin/bats tests/bats/image.bats
+```
+
+## CI/CD
+
+- Uses CircleCI with `drevops/ci-runner:25.9.0` image
+- Publishes to DockerHub:
+  - `main` branch → `canary` tag
+  - Git tags → versioned tag + `latest`
+  - Feature branches → `feature-branch-name` tag (but renovate branches are skipped)
+- Multi-platform builds: `linux/amd64,linux/arm64`
+- Code coverage uploaded to Codecov via kcov
+
+## Important Notes
+
+- Always test changes by committing first (BATS tests copy code from last commit)
+- The entrypoint script should remain minimally modified for easy upstream syncing
+- When updating base image version, follow upstream versioning
+- seed.sh requires being logged into Docker registry (it pushes during buildx)
+- Tests always run for linux/amd64 unless explicitly configured otherwise