What Happens to Bad Records?

Poison Pill Isolation and Failure-Mode-Driven Architecture At intermediate, bad records go to a DLQ. The interviewer then asks: 'How do you architect the entire pipeline around failure modes?' The trap is treating error handling as an afterthought. The senior signal: 'Before I write the first line of transformation code, I enumerate the failure modes - schema drift, poison pills, volume spikes, upstream delays - and design a mitigation for each.' A poison pill is a record that doesn't just fail - it crashes the pipeline. Malformed JSON that causes a deserialization exception. A value that triggers an infinite loop. A record so large it OOMs the worker. The key difference from a normal bad record: poison pills block the pipeline from making progress on any other record. The interviewer want