# commercewerk > commercewerk develops Shopware extensions and custom integrations. Post-Purchase Upsell & Cross-Sell (PPU) is a Shopware 6 extension designed to increase order value with relevant offers after checkout. Accepted products join the existing order. ## PPU: English - [PPU guide](https://commercewerk.de/llms/post-purchase-upsell.en.md): Benefits, use cases and product requirements. - [PPU product page](https://commercewerk.de/en/post-purchase-upsell-shopware): Screenshots, demo and Shopware Store. - [Campaigns](https://commercewerk.de/en/docs/shopware/post-purchase-upsell/campaigns): Cross-sellings, Dynamic Product Groups, fixed products and discounts. - [Payment support](https://commercewerk.de/en/docs/shopware/post-purchase-upsell/payment-methods-and-failure-cases): Supported payment methods, conditions and exclusions. - [Analytics](https://commercewerk.de/en/docs/shopware/post-purchase-upsell/analytics): Actual offer results and revenue-potential estimates. - [ERP integration](https://commercewerk.de/en/docs/shopware/post-purchase-upsell/erp-export): Import orders after offer processing; requirements and limits. - [Compatibility](https://commercewerk.de/en/docs/shopware/post-purchase-upsell/compatibility-and-integration): Current Shopware, PHP and SwagPayPal requirements. - [Changelog](https://commercewerk.de/en/docs/shopware/post-purchase-upsell/changelog): Releases and changes. ## PPU: Deutsch - [PPU-Überblick](https://commercewerk.de/llms/post-purchase-upsell.de.md): Vorteile, Anwendungsfälle und Voraussetzungen. - [PPU-Produktseite](https://commercewerk.de/post-purchase-upsell-shopware): Screenshots, Demo und Shopware Store. - [Kampagnen](https://commercewerk.de/docs/shopware/post-purchase-upsell/campaigns): Cross-Sellings, dynamische Produktgruppen, feste Produkte und Rabatte. - [Zahlungsarten](https://commercewerk.de/docs/shopware/post-purchase-upsell/payment-methods-and-failure-cases): Unterstützte Zahlungsarten, Voraussetzungen und Ausschlüsse. - [Analyse](https://commercewerk.de/docs/shopware/post-purchase-upsell/analytics): Tatsächliche Angebotsergebnisse und Schätzungen zum Umsatzpotenzial. - [ERP-Integration](https://commercewerk.de/docs/shopware/post-purchase-upsell/erp-export): Bestellungen nach der Angebotsverarbeitung importieren; Voraussetzungen und Grenzen. - [Kompatibilität](https://commercewerk.de/docs/shopware/post-purchase-upsell/compatibility-and-integration): Aktuelle Anforderungen an Shopware, PHP und SwagPayPal. - [Changelog](https://commercewerk.de/docs/shopware/post-purchase-upsell/changelog): Veröffentlichungen und Änderungen. ## Optional - [QuickAuth documentation (English)](https://commercewerk.de/en/docs/shopware/quick-auth): Login using email or SMS codes. - [commercewerk (English)](https://commercewerk.de/en): Company and services. - [QuickAuth documentation (German)](https://commercewerk.de/docs/shopware/quick-auth): German setup and usage guide. - [commercewerk (German)](https://commercewerk.de/): Company and services in German.