An Apex Language developer designs, develops, and manages software applications using Salesforce's proprietary programming language, Apex. Their responsibilities include creating robust, scalable, secure applications to customize Salesforce.com applications, developing integrations with external systems, writing and maintaining code, and debugging software applications. They also work on implementing complex business processes using triggers, workflows, and visual force pages. They often collaborate with other developers, admins, and business analysts to understand requirements and deliver solutions. They also ensure code is optimized, well-documented, and adheres to best practices. Mastery of Apex language also involves keeping up with Salesforce updates and changes.