Replit deployment

Kotlin Compilation Error on Replit

Kotlin compilation fails with type or null safety errors. Build aborts before completion.

Kotlin's strict null safety and type system catch errors at compile time.

Error Messages You Might See

Type mismatch Un-nullable type is expected Unresolved reference
Type mismatchUn-nullable type is expectedUnresolved reference

Common Causes

  1. Nullable type not properly checked (lateinit without init)
  2. Type mismatch (String vs Int)
  3. Class or function not found
  4. Kotlin stdlib not in dependencies
  5. Plugin version incompatible with Kotlin version

How to Fix It

Check error message for line number and fix type/null issues. Ensure kotlin-stdlib in dependencies. Use lateinit var with caution. Check Kotlin version in gradle matches plugin. For Spring Boot, use kotlin-spring plugin for no-arg constructors. Use -Xjsr305=strict for strict null handling.

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Frequently Asked Questions

What's the easiest Kotlin issue to fix?

Type mismatches. Check the error line and adjust types to match

Do I need kotlin-spring plugin?

Yes, for Spring Data JPA entities without explicit no-arg constructors

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