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+# AGENTS.md
+
+## Project: Roux
+
+A personal/family recipe management site. See [README.org](./README.org) for full project description.
+
+### Key facts
+
+- **Backend**: Haskell + SQLite
+- **Frontend**: Static HTML + Pico CSS
+- **Recipe format**: Cooklang (https://cooklang.org/)
+- **Development**: Docker-based; nothing required locally except Docker
+- **Subprojects**:
+  - `cooklang-hs/` — Cooklang parser in Haskell
+  - `roux-server/` — Web server, file indexing, HTML rendering
+
+### Development environment
+
+All Haskell tooling runs via the `hs` wrapper script, which runs inside the
+[flipstone/haskell-tools](https://github.com/flipstone/haskell-tools) Docker
+image. Adopted from the pattern in the Atlas project.
+
+#### Setup
+
+1. Create the `hs` wrapper script in the project root:
+
+```bash
+cat > hs << 'SCRIPT'
+#!/usr/bin/env bash
+# Thin wrapper to run Haskell tooling (stack, hpack, fourmolu, hlint, ...)
+# inside the flipstone/haskell-tools Docker image. Usage: ./hs <cmd> [args]
+# e.g. ./hs stack build, ./hs stack test, ./hs hpack, ./hs fourmolu
+set -euo pipefail
+
+IMAGE="${HAWAT_HASKELL_TOOLS_IMAGE:-ghcr.io/flipstone/haskell-tools:debian-ghc-9.10.3-5d6640d}"
+PROJECT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+STACK_ROOT_HOST="${PROJECT_DIR}/.stack-root"
+
+mkdir -p "${STACK_ROOT_HOST}"
+
+exec docker run --rm -i $([ -t 0 ] && printf -- -t) \
+  -v "${PROJECT_DIR}:/work" \
+  -v "${STACK_ROOT_HOST}:/stack-root" \
+  -e STACK_ROOT=/stack-root \
+  -w /work \
+  "${IMAGE}" \
+  "$@"
+SCRIPT
+chmod +x hs
+```
+
+2. Create `.stack-root/` in the project root to persist GHC/cache across runs:
+
+```bash
+mkdir -p .stack-root
+```
+
+3. Initialize a Haskell project with `stack` or `hpack`:
+
+```bash
+./hs stack new cooklang-hs simple --dir cooklang-hs
+# or for an existing project:
+./hs stack build
+```
+
+#### Usage examples
+
+```bash
+./hs stack build              # Build all subprojects
+./hs stack test                # Run tests
+./hs stack ghci                # REPL
+./hs hpack                     # Regenerate .cabal from package.yaml
+./hs fourmolu -i **/*.hs       # Format Haskell sources
+./hs hlint src/                # Lint sources
+```
+
+#### Environment variables
+
+- `HAWAT_HASKELL_TOOLS_IMAGE` — override the Docker image tag (defaults to
+  `ghcr.io/flipstone/haskell-tools:debian-ghc-9.10.3-5d6640d`)
+
+### Agent conventions
+
+- Prefer the `hs` wrapper over local tooling — match the Docker-first dev environment.
+- Run `./hs stack build` and `./hs stack test` before marking work as complete.
+- When adding a new subproject (e.g. `roux-server`), initialize it with `./hs stack new`.
+- Use `hpack` (via `./hs hpack`) for package metadata in `package.yaml` format.
+- When agent-created files are owned by root, fix ownership with `sudo chown -R $(id -u):$(id -g) .`.
diff --git a/hs b/hs
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+++ b/hs
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+#!/usr/bin/env bash
+# Thin wrapper to run Haskell tooling (stack, hpack, fourmolu, hlint, ...)
+# inside the flipstone/haskell-tools Docker image. Usage: ./hs <cmd> [args]
+# e.g. ./hs stack build, ./hs stack test, ./hs hpack, ./hs fourmolu
+set -euo pipefail
+
+IMAGE="${HAWAT_HASKELL_TOOLS_IMAGE:-ghcr.io/flipstone/haskell-tools:debian-ghc-9.10.3-5d6640d}"
+PROJECT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+STACK_ROOT_HOST="${PROJECT_DIR}/.stack-root"
+
+mkdir -p "${STACK_ROOT_HOST}"
+
+exec docker run --rm -i $([ -t 0 ] && printf -- -t) \
+  -v "${PROJECT_DIR}:/work" \
+  -v "${STACK_ROOT_HOST}:/stack-root" \
+  -e STACK_ROOT=/stack-root \
+  -w /work \
+  "${IMAGE}" \
+  "$@"