What’s a “code debt” in email templates?

Code debt in email templates is the accumulation of unnecessary, outdated, or suboptimal code that makes templates harder to maintain and potentially worse-performing. It accrues naturally: old CSS hacks for clients that have since improved, styles for design elements that were removed but whose code wasn't, inline styles copy-pasted when they could be consolidated, and workarounds that were never cleaned up after the underlying problem was fixed.

Symptoms of code debt include: bloated file sizes (emails that should be 50KB are 150KB), maintenance difficulty (simple changes require touching code in multiple places), rendering unpredictability (nobody remembers why certain code exists, so nobody removes it), and slow production cycles (editing templates feels risky because the codebase is fragile). High debt also correlates with rendering bugs-complex, tangled code is more likely to break.

Address code debt through periodic refactoring: remove unused CSS, consolidate duplicate styles, delete commented-out code blocks, and simplify structures. Document what remains so future editors understand why specific code exists. Consider a full template rebuild when debt becomes unmanageable. Code debt is invisible until it causes problems, and by then, the cleanup is expensive. Small, regular investments in template hygiene prevent large future crises.