Design a real-time chat application like Slack or WhatsApp — Delivery Hero interview
Reported in Delivery Hero European engineering loops. Mid-to-senior design spanning WebSockets, message storage, and presence.
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Reported in Delivery Hero European engineering loops. Mid-to-senior design spanning WebSockets, message storage, and presence.
Reported in Delivery Hero European engineering loops. Caching patterns for system design and backend performance tuning.
Reported in Delivery Hero European engineering loops. Infrastructure design question covering L4/L7 balancers and health checks.
Reported in Delivery Hero European engineering loops. Senior system design combining sharding, eviction, consistency, and observability.
Reported in Delivery Hero European engineering loops. System design problem testing reliability, fan-out, and channel abstraction.
Reported in Delivery Hero European engineering loops. System design interview around indexing, ranking, and freshness.
Reported in Delivery Hero European engineering loops. Critical design topic focused on correctness under retries and failures.
Reported in Delivery Hero European engineering loops. Observability architecture interview question for platform roles.
Reported in Delivery Hero European engineering loops. System design exercise emphasizing control plane and low-latency reads.
Reported in Delivery Hero European engineering loops. System design topic around edge caching, invalidation, and latency.
Reported in Delivery Hero European engineering loops. Object model design for template rendering and channel-specific formatting.
Reported in Delivery Hero European engineering loops. Frequently asked at European fintechs dealing with PSD2 and AML controls.
Reported in Delivery Hero European engineering loops. Often appears in enterprise and platform interviews at EU cloud and SaaS companies.