What are common architecture anti-patterns?

Catch these early:

• Adding expensive technology without a measured bottleneck or a trained owner
• Direct client access to privileged database tables, or exposed storage buckets
• Unbounded list responses and full-table scans on every homepage refresh
• Long database transactions holding locks while calling external APIs
• Retry loops without deadlines, idempotency or backoff
• Ignoring CI because the runner broke, or running migrations out of order
• Several people or agents editing the same migration, state machine or production branch
• Calling it done because unit tests pass while authorization, recovery and peak traffic are untested
• A very fast app that gets the money wrong — operational correctness comes first