How do you plan for Christmas + Berlin Fashion Week + Black Friday peak in Germany?

Germany has the highest per-capita retail spending in EU during Christmas (Dec 1-24 hammer-window), bigger by per-capita than UK Boxing Day. Black Friday + Cyber Monday arrived in DE late but is now huge (~€5bn weekend). Berlin Fashion Week in January and July drives a Mitte / Kreuzberg DTC spike. Berlinale film festival in February adds a 10-day retail bump. We build a war-room: (1) synthetic load test at 25× baseline using k6 or JMeter two weeks before peak; (2) Redis cluster + Varnish FPC with smart-purge, never full flush; (3) queue-isolated checkout, checkout traffic on its own PHP-FPM pool so a catalogue spike can't starve Klarna confirmations; (4) Adyen / Stripe tokenisation for repeat buyers so card-form latency drops 80%; (5) read-replica MySQL for product browsing; (6) Cloudflare or Fastly in front of Magento. Karneval (Cologne / Düsseldorf, Feb) is lighter on Berlin, but Tag der Deutschen Einheit (Oct 3) does drive a retail bump.