What are some common challenges faced by contractual full stack Java developers when integrating with existing systems?

Contractual Full Stack Java Developers often encounter challenges when integrating new features with legacy systems, including inconsistent documentation, differing technology stacks, and limited access to internal resources. Navigating these issues requires strong problem-solving skills, effective communication with in-house teams, and the ability to quickly understand existing codebases. Working contractually also means managing time efficiently to meet project milestones despite these integration hurdles.