A small bug in Knight Capital's trading system led to a $440 million loss in just 45 minutes, nearly bankrupting the company.The domino effect in software development can cause cascading issues, affecting entire applications.Startup survival can be threatened by website crashes, payment bugs, and data corruption leading to lost customers, revenue, and trust.The hidden killer for startups is the cascade of events triggered by a single bug, such as customer complaints, bad reviews, and employee departures.Common triggers for the domino effect include minor changes leading to unexpected consequences and rushed feature deployments without proper testing.Red flags for CTOs, founders, and developers can help spot potential domino risks before they escalate.The startup survival kit includes rules like the 10-Minute Rule, Blast Radius Check, and avoiding deployments on Fridays.Developers can use tools like dependency mapping, considering 'What If' scenarios, and ensuring rollback plans are in place before deployment.Quick domino stoppers like circuit breakers, gradual rollouts, and effective monitoring can help prevent cascading failures.Netflix's approach to chaos engineering, circuit breakers, and gradual rollouts exemplifies strategies to avoid domino disasters.