diff --git a/Dockerfile b/Dockerfile
index abd2d5a..29890c9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -26,7 +26,9 @@ FROM node:22-bookworm-slim AS assets
 
 WORKDIR /app
 COPY package.json pnpm-lock.yaml ./
-RUN npm install -g pnpm && pnpm install --frozen-lockfile --ignore-scripts
+# Corepack ships with Node and activates the pnpm version pinned in
+# package.json's "packageManager" field — no npm bootstrap needed.
+RUN corepack enable && pnpm install --frozen-lockfile --ignore-scripts
 COPY . .
 COPY --from=builder /home/timetracker/app/ts/generated ./ts/generated
 RUN pnpm tailwindcss -i ./common/input.css -o ./games/static/base.css \
diff --git a/package.json b/package.json
index 7666c0d..a156fbc 100644
--- a/package.json
+++ b/package.json
@@ -1,4 +1,5 @@
 {
+  "packageManager": "pnpm@10.33.0",
   "devDependencies": {
     "@tailwindcss/forms": "^0.5.7",
     "@tailwindcss/typography": "^0.5.13",