diff --git a/README.md b/README.md
index 6c13c20..a4002bb 100644
--- a/README.md
+++ b/README.md
@@ -1,8 +1,8 @@
 # frontend-svelte
 
-Copier template for a SvelteKit frontend, either as a `frontend/` part next to other parts or alone at the root of the project (`layout`): SvelteKit on Bun with Tailwind v4, ultracite (biome) and optional shadcn-svelte, served by a Bun server with SSR, as a static SPA behind `serve.ts`, or as a static SPA that the backend api serves from `frontend/build`.
+Copier template for a SvelteKit frontend, either as a `frontend/` part next to other parts or alone at the root of the project (`layout`): SvelteKit on Bun with Tailwind v4, ultracite (biome) or ESLint + Prettier (`linter`) and optional shadcn-svelte, served by a Bun server with SSR, as a static SPA behind `serve.ts`, or as a static SPA that the backend api serves from `frontend/build`.
 
-Ships `frontend/docker-compose.yml` with root-relative paths and profiles per service, `docker-compose.override.yml.example` (the `caddy` network aliases, copied by `make env`), a `Makefile` with `fmt`, `check`, `build` and `dev`, `.env.example`, `CLAUDE.md`, `.claude/rules` for Svelte and ultracite. The Svelte MCP server comes from `infra`. Applied on top of the `infra` template, `layout: parts` or `layout: single` respectively.
+Ships `frontend/docker-compose.yml` with root-relative paths and profiles per service, `docker-compose.override.yml.example` (the `caddy` network aliases, copied by `make env`), a `Makefile` with `fmt`, `check`, `build` and `dev`, `.env.example`, `CLAUDE.md`, `.claude/rules` for Svelte (and ultracite with biome). The image is built in stages: `.env` is in the build context, since `$env/static/*` are inlined at build time, and stays in the builder stage; the runtime image gets `build/` and production dependencies only. The Svelte MCP server comes from `infra`. Applied on top of the `infra` template, `layout: parts` or `layout: single` respectively.
 
 ```sh
 copier copy --trust -d project_name="My Thing" -d serve=bun <this-repo> <dest>
diff --git a/copier.yml b/copier.yml
index 9d8124b..11fd5c2 100644
--- a/copier.yml
+++ b/copier.yml
@@ -37,6 +37,14 @@ ui_library:
     shadcn-svelte: shadcn
   default: none
 
+linter:
+  type: str
+  help: Linter and formatter
+  choices:
+    Biome with the ultracite preset: biome
+    ESLint + Prettier (the sv create setup): eslint
+  default: biome
+
 install_deps:
   type: bool
   help: bun install after generation
@@ -58,4 +66,6 @@ prefix:
   default: "{{ 'frontend/' if layout == 'part' else '' }}"
 
 _tasks:
-  - "{% if _copier_operation == 'copy' and install_deps %}sh -c 'cd {{ part_dir }} && bun install'{% else %}true{% endif %}"
+  # prettier-plugin-tailwindcss and biome sort classes differently, the
+  # sources follow biome: an eslint project is formatted once, right away.
+  - "{% if _copier_operation == 'copy' and install_deps %}sh -c 'cd {{ part_dir }} && bun install{% if linter == 'eslint' %} && bun run fix{% endif %}'{% else %}true{% endif %}"
diff --git a/template/.claude/rules/ultracite.md b/template/.claude/rules/{% if linter == 'biome' %}ultracite.md{% endif %}
similarity index 100%
rename from template/.claude/rules/ultracite.md
rename to template/.claude/rules/{% if linter == 'biome' %}ultracite.md{% endif %}
diff --git a/template/.claude/settings.json.jinja b/template/.claude/settings.json.jinja
index c04b1b8..da0979e 100644
--- a/template/.claude/settings.json.jinja
+++ b/template/.claude/settings.json.jinja
@@ -4,7 +4,7 @@
       {
         "hooks": [
           {
-            "command": "{% if layout == 'part' %}cd frontend && {% endif %}bun run fix --skip=correctness/noUnusedImports",
+            "command": "{% if layout == 'part' %}cd frontend && {% endif %}bun run fix{% if linter == 'biome' %} --skip=correctness/noUnusedImports{% endif %}",
             "type": "command"
           }
         ],
diff --git a/template/{{ part_dir }}/.dockerignore b/template/{{ part_dir }}/.dockerignore
index 1048241..ed46f37 100644
--- a/template/{{ part_dir }}/.dockerignore	
+++ b/template/{{ part_dir }}/.dockerignore	
@@ -1,5 +1,7 @@
 node_modules
 .svelte-kit
 build
-.env
+# .env goes into the build: $env/static/public (and static/private) are
+# inlined at build time from it. It stays in the builder stage, the runtime
+# image gets build/ only. Local overrides (.env.local and the like) stay out.
 .env.*
diff --git a/template/{{ part_dir }}/Makefile.jinja b/template/{{ part_dir }}/Makefile.jinja
index 724896d..8405f28 100644
--- a/template/{{ part_dir }}/Makefile.jinja	
+++ b/template/{{ part_dir }}/Makefile.jinja	
@@ -1,5 +1,5 @@
 COMPOSE := {% if layout == 'part' %}cd .. && {% endif %}docker compose
-{% if serve != 'api' %}IMAGE := {{ project_slug }}/frontend
+{% if serve != 'api' %}IMAGE := {{ project_slug | replace('_', '-') }}/frontend
 {% endif %}changed = ! git diff --quiet $(1) -- $(2) 2>/dev/null
 stamp = { git update-ref $(1) HEAD 2>/dev/null || true; }
 
diff --git a/template/{{ part_dir }}/docker-compose.yml.jinja b/template/{{ part_dir }}/docker-compose.yml.jinja
index c9a4675..4be1915 100644
--- a/template/{{ part_dir }}/docker-compose.yml.jinja	
+++ b/template/{{ part_dir }}/docker-compose.yml.jinja	
@@ -1,7 +1,7 @@
 services:
 {% if serve != 'api' %}  frontend:
     build: {{ part_dir }}
-    image: {{ project_slug }}/frontend
+    image: {{ project_slug | replace('_', '-') }}/frontend
     profiles: [frontend, services]
     restart: unless-stopped
     env_file:
diff --git a/template/{{ part_dir }}/package.json.jinja b/template/{{ part_dir }}/package.json.jinja
index a41a597..1d83f87 100644
--- a/template/{{ part_dir }}/package.json.jinja	
+++ b/template/{{ part_dir }}/package.json.jinja	
@@ -8,14 +8,18 @@
     "check": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json",
     "check:watch": "svelte-kit sync && svelte-check --tsconfig ./tsconfig.json --watch",
     "dev": "vite dev",
+{%- if linter == 'biome' %}
     "fix": "ultracite fix",
     "lint": "ultracite check",
+{%- else %}
+    "fix": "prettier --write . && eslint --fix .",
+    "lint": "prettier --check . && eslint .",
+{%- endif %}
     "prepare": "svelte-kit sync || echo ''",
     "preview": "vite preview"
   },
   "devDependencies": {
 {%- set deps = {
-  "@biomejs/biome": "2.5.13",
   "@sveltejs/kit": "^2.63.0",
   "@sveltejs/vite-plugin-svelte": "^7.1.2",
   "@tailwindcss/vite": "^4.3.0",
@@ -24,9 +28,23 @@
   "svelte-check": "^4.6.0",
   "tailwindcss": "^4.3.0",
   "typescript": "^6.0.3",
-  "ultracite": "7.12.0",
   "vite": "^8.0.16",
 } -%}
+{%- if linter == 'biome' %}{% set _ = deps.update({
+  "@biomejs/biome": "2.5.13",
+  "ultracite": "7.12.0",
+}) %}{% else %}{% set _ = deps.update({
+  "@eslint/compat": "^2.1.1",
+  "@eslint/js": "^10.0.1",
+  "eslint": "^10.12.0",
+  "eslint-config-prettier": "^10.1.8",
+  "eslint-plugin-svelte": "^3.23.0",
+  "globals": "^17.13.0",
+  "prettier": "^3.9.9",
+  "prettier-plugin-svelte": "^4.1.1",
+  "prettier-plugin-tailwindcss": "^0.8.1",
+  "typescript-eslint": "^8.71.1",
+}) %}{% endif -%}
 {%- if frontend_adapter == 'bun' %}{% set _ = deps.update({"svelte-adapter-bun": "^1.0.1"}) %}{% else %}{% set _ = deps.update({"@sveltejs/adapter-static": "^3.0.10"}) %}{% endif -%}
 {%- if ui_library == 'shadcn' %}{% set _ = deps.update({
   "@internationalized/date": "^3.12.0",
diff --git a/template/{{ part_dir }}/src/lib/index.ts b/template/{{ part_dir }}/src/lib/index.ts
deleted file mode 100644
index 7c43079..0000000
--- a/template/{{ part_dir }}/src/lib/index.ts	
+++ /dev/null
@@ -1,2 +0,0 @@
-// place files you want to import through the `$lib` alias in this folder.
-// biome-ignore-all lint/suspicious/noEmptySource: temporary
diff --git a/template/{{ part_dir }}/src/lib/index.ts.jinja b/template/{{ part_dir }}/src/lib/index.ts.jinja
new file mode 100644
index 0000000..5830bbc
--- /dev/null
+++ b/template/{{ part_dir }}/src/lib/index.ts.jinja	
@@ -0,0 +1,3 @@
+// place files you want to import through the `$lib` alias in this folder.
+{% if linter == 'biome' %}// biome-ignore-all lint/suspicious/noEmptySource: temporary
+{% endif %}
\ No newline at end of file
diff --git a/template/{{ part_dir }}/svelte.config.js.jinja b/template/{{ part_dir }}/svelte.config.js.jinja
index 94f7031..4fa3b8c 100644
--- a/template/{{ part_dir }}/svelte.config.js.jinja	
+++ b/template/{{ part_dir }}/svelte.config.js.jinja	
@@ -5,8 +5,8 @@ import adapter from "svelte-adapter-bun";
 const config = {
   compilerOptions: {
     runes: ({ filename }) =>
-      // biome-ignore lint/performance/useTopLevelRegex: svelte default behaviour
-      filename.split(/[/\\]/).includes("node_modules") ? undefined : true,
+{% if linter == 'biome' %}      // biome-ignore lint/performance/useTopLevelRegex: svelte default behaviour
+{% endif %}      filename.split(/[/\\]/).includes("node_modules") ? undefined : true,
   },
   kit: {
     adapter: adapter(),
diff --git a/template/{{ part_dir }}/{% if layout == 'root' %}README.md{% endif %}.jinja b/template/{{ part_dir }}/{% if layout == 'root' %}README.md{% endif %}.jinja
index ba8d1a5..82b771f 100644
--- a/template/{{ part_dir }}/{% if layout == 'root' %}README.md{% endif %}.jinja	
+++ b/template/{{ part_dir }}/{% if layout == 'root' %}README.md{% endif %}.jinja	
@@ -11,4 +11,6 @@ make recreate
 
 To deploy, `git pull && make deploy`. It runs `make pre-deploy`, which rebuilds the image only when something in the repository changed, then `docker compose up -d`. A deploy system with its own `up` step calls `make pre-deploy` before it and `make post-deploy` after. What was built is remembered as `refs/deploy/*` in the clone.
 
+In the fleet, production is deployed from `infra/komodo` instead (git mode of Komodo, see `docs/architecture.md` there): Komodo clones this repo, and a layer plus `deploy.sh` in the stack's directory tag images by the hash of what they bake in and write `.env` from sops. The repo only has to stay a plain recipe: images built from `build:` in compose, `caddy/site.caddy`. `make deploy` and `refs/deploy/*` are for a checkout deployed by hand.
+
 `make dev` runs the Vite dev server on the host, `make fmt` formats, `make check` runs svelte-check and the linter.
diff --git a/template/{{ part_dir }}/biome.jsonc.jinja b/template/{{ part_dir }}/{% if linter == 'biome' %}biome.jsonc{% endif %}.jinja
similarity index 100%
rename from template/{{ part_dir }}/biome.jsonc.jinja
rename to template/{{ part_dir }}/{% if linter == 'biome' %}biome.jsonc{% endif %}.jinja
diff --git a/template/{{ part_dir }}/{% if linter == 'eslint' %}.prettierignore{% endif %} b/template/{{ part_dir }}/{% if linter == 'eslint' %}.prettierignore{% endif %}
new file mode 100644
index 0000000..7a657b0
--- /dev/null
+++ b/template/{{ part_dir }}/{% if linter == 'eslint' %}.prettierignore{% endif %}	
@@ -0,0 +1,14 @@
+# Package managers
+package-lock.json
+pnpm-lock.yaml
+yarn.lock
+bun.lock
+bun.lockb
+
+# Written by copier and the infra template, not by hand
+.copier/
+*.md
+renovate.jsonc
+
+# Miscellaneous
+/static/
diff --git a/template/{{ part_dir }}/{% if linter == 'eslint' %}.prettierrc{% endif %} b/template/{{ part_dir }}/{% if linter == 'eslint' %}.prettierrc{% endif %}
new file mode 100644
index 0000000..15188a8
--- /dev/null
+++ b/template/{{ part_dir }}/{% if linter == 'eslint' %}.prettierrc{% endif %}	
@@ -0,0 +1,6 @@
+{
+  "trailingComma": "es5",
+  "plugins": ["prettier-plugin-svelte", "prettier-plugin-tailwindcss"],
+  "overrides": [{ "files": "*.svelte", "options": { "parser": "svelte" } }],
+  "tailwindStylesheet": "./src/routes/layout.css"
+}
diff --git a/template/{{ part_dir }}/{% if linter == 'eslint' %}eslint.config.js{% endif %}.jinja b/template/{{ part_dir }}/{% if linter == 'eslint' %}eslint.config.js{% endif %}.jinja
new file mode 100644
index 0000000..049832f
--- /dev/null
+++ b/template/{{ part_dir }}/{% if linter == 'eslint' %}eslint.config.js{% endif %}.jinja	
@@ -0,0 +1,49 @@
+import { fileURLToPath } from "node:url";
+import { includeIgnoreFile } from "@eslint/compat";
+import js from "@eslint/js";
+import prettier from "eslint-config-prettier";
+import svelte from "eslint-plugin-svelte";
+import { defineConfig } from "eslint/config";
+import globals from "globals";
+import ts from "typescript-eslint";
+import svelteConfig from "./svelte.config.js";
+
+const gitignorePath = fileURLToPath(new URL("./.gitignore", import.meta.url));
+
+export default defineConfig(
+  includeIgnoreFile(gitignorePath),
+  js.configs.recommended,
+  ...ts.configs.recommended,
+  ...svelte.configs.recommended,
+  prettier,
+  ...svelte.configs.prettier,
+  {
+    languageOptions: { globals: { ...globals.browser, ...globals.node } },
+    rules: {
+      // typescript-eslint recommends against no-undef on TypeScript projects:
+      // https://typescript-eslint.io/troubleshooting/faqs/eslint/#i-get-errors-from-the-no-undef-rule-about-global-variables-not-being-defined-even-though-there-are-no-typescript-errors
+      "no-undef": "off",
+    },
+  },
+{%- if ui_library == 'shadcn' %}
+  {
+    // shadcn-svelte primitives are copied in and changed upstream only.
+    files: ["src/lib/components/ui/**"],
+    rules: {
+      "@typescript-eslint/no-explicit-any": "off",
+      "svelte/no-navigation-without-resolve": "off",
+    },
+  },
+{%- endif %}
+  {
+    files: ["**/*.svelte", "**/*.svelte.ts", "**/*.svelte.js"],
+    languageOptions: {
+      parserOptions: {
+        extraFileExtensions: [".svelte"],
+        parser: ts.parser,
+        projectService: true,
+        svelteConfig,
+      },
+    },
+  }
+);
diff --git a/template/{{ part_dir }}/{% if serve != 'api' %}Dockerfile{% endif %}.jinja b/template/{{ part_dir }}/{% if serve != 'api' %}Dockerfile{% endif %}.jinja
index 96377a5..c2512dc 100644
--- a/template/{{ part_dir }}/{% if serve != 'api' %}Dockerfile{% endif %}.jinja	
+++ b/template/{{ part_dir }}/{% if serve != 'api' %}Dockerfile{% endif %}.jinja	
@@ -1,20 +1,44 @@
 {% if frontend_adapter == 'bun' -%}
-FROM oven/bun:alpine
+FROM oven/bun:alpine AS deps
 
 ENV TERM=xterm-256color
 ENV COLORTERM=truecolor
+ENV BUN_INSTALL_CACHE_DIR=/bun-cache
 
 WORKDIR /app
 
 COPY package.json bun.lock* ./
 
-RUN bun install --frozen-lockfile
+RUN --mount=type=cache,target=/bun-cache bun install --frozen-lockfile
+
+
+# .env is in the context ($env/static/* are inlined at build) and stays in
+# this stage: the runtime image below gets build/ and production deps only.
+FROM deps AS builder
 
 COPY . .
 
 RUN bun --bun svelte-kit sync
 RUN bun --bun run build
 
+
+FROM oven/bun:alpine AS runtime
+
+ENV NODE_ENV=production
+# The cache mount only holds files; without the variable bun caches into
+# ~/.bun inside the image.
+ENV BUN_INSTALL_CACHE_DIR=/bun-cache
+
+WORKDIR /app
+
+COPY package.json bun.lock* ./
+
+RUN --mount=type=cache,target=/bun-cache bun install --frozen-lockfile --production
+
+COPY --from=builder /app/build ./build
+
+EXPOSE 3000
+
 ENTRYPOINT ["bun"]
 CMD ["build/index.js"]
 {%- else -%}