How a delivery app survives failure
Event sourcing stores every change as an immutable log, so a service can rebuild its state after a crash. When one order spans several services, the saga pattern undoes the finished steps if a later step fails.
lo prathi change ni oka la store chestharu. Anduke crash ayina taruvatha kuda service thana state ni malli build cheskogaladu. Oka order chala services meedha nadisthe, tarvatha step fail ayinappudu aipoyina steps ni undo chesthundi.