diff --git a/README.md b/README.md
index a3e0fb5..47ec118 100644
--- a/README.md
+++ b/README.md
@@ -1,10 +1,10 @@
 # infra
 
-Copier template for the root of a project: `docker-compose.yml` that includes every part, a `Makefile` that drives compose and delegates `fmt`, `check` and `build` to parts, `.env.example`, `.gitignore`, `CLAUDE.md` and pre-commit hooks.
+Copier template for the root of a project. With `layout: parts` it ships a `docker-compose.yml` that includes every part, a `Makefile` that drives compose and delegates `fmt`, `check` and `build` to parts, and an `.env.example` whose `COMPOSE_FILE` adds each part's `docker-compose.local.yml`. With `layout: single` a part template renders straight into the root and infra ships only `.gitignore`, `CLAUDE.md` and pre-commit hooks.
 
 A part is a directory with:
 
-- `docker-compose.yml` with root-relative paths, plus `docker-compose.local.yml` and `docker-compose.prod.yml` selected by `COMPOSE_ENV`
+- `docker-compose.yml` with root-relative paths, plus `docker-compose.local.yml` and `docker-compose.prod.yml` picked through `COMPOSE_FILE` in the root `.env`
 - `Makefile` with `fmt`, `check` and `build` targets
 - `.env.example` appended to the root `.env` by `make env`
 - `CLAUDE.md` with the part's checking commands
@@ -12,6 +12,6 @@ A part is a directory with:
 Application services carry the `services` profile, databases and other infrastructure carry `external`.
 
 ```sh
-copier copy --trust -d 'parts=["backend","frontend"]' <this-repo> <dest>
+copier copy --trust -d layout=parts -d 'parts=["backend","frontend"]' <this-repo> <dest>
 copier update -a .copier/infra.yml
 ```
diff --git a/copier.yml b/copier.yml
index 0a9ac7d..958fb6d 100644
--- a/copier.yml
+++ b/copier.yml
@@ -4,9 +4,18 @@ _answers_file: .copier/infra.yml
 _envops:
   keep_trailing_newline: true
 
+layout:
+  type: str
+  help: Where the code lives
+  choices:
+    Parts in their own directories: parts
+    A single part at the root: single
+  default: parts
+
 parts:
   type: str
   multiselect: true
+  when: "{{ layout == 'parts' }}"
   help: Parts that live in their own directory with a docker-compose.yml and a Makefile
   choices:
     backend: backend
diff --git a/template/.env.example b/template/.env.example
deleted file mode 100644
index 2bcba39..0000000
--- a/template/.env.example
+++ /dev/null
@@ -1 +0,0 @@
-COMPOSE_ENV=local
diff --git a/template/.gitignore b/template/.gitignore
deleted file mode 100644
index 817009b..0000000
--- a/template/.gitignore
+++ /dev/null
@@ -1,6 +0,0 @@
-.env
-.env.*
-!.env.example
-docker-compose.override.yml
-.DS_Store
-.idea
diff --git a/template/.gitignore.jinja b/template/.gitignore.jinja
new file mode 100644
index 0000000..2ea4c36
--- /dev/null
+++ b/template/.gitignore.jinja
@@ -0,0 +1,16 @@
+.env
+.env.*
+!.env.example
+docker-compose.override.yml
+.DS_Store
+.idea
+{% if layout == 'single' %}.venv/
+__pycache__/
+*.pyc
+.ruff_cache/
+.pytest_cache/
+sessions/*.session*
+node_modules/
+.svelte-kit/
+/build/
+{% endif %}
diff --git a/template/.pre-commit-config.yaml.jinja b/template/.pre-commit-config.yaml.jinja
index e1b7c44..eef3b45 100644
--- a/template/.pre-commit-config.yaml.jinja
+++ b/template/.pre-commit-config.yaml.jinja
@@ -1,7 +1,17 @@
 repos:
   - repo: local
-    hooks:{% if not parts %} []{% endif %}
-{% for part in parts %}      - id: {{ part }}-fmt
+    hooks:{% if layout == 'parts' and not parts %} []{% endif %}
+{% if layout == 'single' %}      - id: fmt
+        name: fmt
+        entry: make fmt
+        language: system
+        pass_filenames: false
+      - id: check
+        name: check
+        entry: make check
+        language: system
+        pass_filenames: false
+{% endif %}{% for part in parts %}      - id: {{ part }}-fmt
         name: {{ part }} fmt
         entry: make -C {{ part }} fmt
         language: system
diff --git a/template/docker-compose.yml.jinja b/template/docker-compose.yml.jinja
deleted file mode 100644
index cc92863..0000000
--- a/template/docker-compose.yml.jinja
+++ /dev/null
@@ -1,7 +0,0 @@
-{% if parts %}include:
-{% for part in parts %}  - path:
-      - {{ part }}/docker-compose.yml
-      - {{ part }}/docker-compose.${COMPOSE_ENV:-local}.yml
-    project_directory: .
-{% endfor %}{% else %}services: {}
-{% endif %}
diff --git a/template/{% if layout == 'parts' %}.env.example{% endif %}.jinja b/template/{% if layout == 'parts' %}.env.example{% endif %}.jinja
new file mode 100644
index 0000000..919d6e4
--- /dev/null
+++ b/template/{% if layout == 'parts' %}.env.example{% endif %}.jinja	
@@ -0,0 +1,2 @@
+{% if parts %}COMPOSE_FILE=docker-compose.yml{% for part in parts %}:{{ part }}/docker-compose.local.yml{% endfor %}
+{% endif %}
diff --git a/template/Makefile b/template/{% if layout == 'parts' %}Makefile{% endif %}
similarity index 100%
rename from template/Makefile
rename to template/{% if layout == 'parts' %}Makefile{% endif %}
diff --git a/template/{% if layout == 'parts' %}docker-compose.yml{% endif %}.jinja b/template/{% if layout == 'parts' %}docker-compose.yml{% endif %}.jinja
new file mode 100644
index 0000000..322a6ce
--- /dev/null
+++ b/template/{% if layout == 'parts' %}docker-compose.yml{% endif %}.jinja	
@@ -0,0 +1,5 @@
+{% if parts %}include:
+{% for part in parts %}  - path: {{ part }}/docker-compose.yml
+    project_directory: .
+{% endfor %}{% else %}services: {}
+{% endif %}