<p>E-commerce platforms can utilize managed ecosystems to integrate diverse, often globally dispersed participants, including users, sellers, and intermediaries. As key ecosystem participants, search engines play a critical role in channeling user traffic across borders. Through algorithmic matching of user queries with relevant product offerings, search engines enable managed ecosystems to adapt to cross-border demand shifts. Using the Russia–Ukraine conflict as an exogenous shock, we employ a difference-in-differences (DiD) design to analyze changes in foreign user traffic to e-commerce platforms in neighboring and non-neighboring countries. We find that neighboring countries’ platforms received a notable increase in international user traffic following the geopolitical conflict. This effect was particularly pronounced for e-commerce platforms that effectively optimized product keywords to target user search queries. Specifically, platforms can increase niche focus by targeting unique keywords that competitors neglect, or increase mass appeal by targeting popular keywords to reach a broad audience. Our findings highlight cross-border user traffic as a distinct form of international involvement, enabling e-commerce platforms to engage foreign users in cyberspace before transactions occur. By examining the pre-transactional user acquisition processes, this study advances the international business literature by introducing cross-border user traffic in managed ecosystems as a key pathway for digital internationalization.</p>