Java API Developer

3Core Systems Inc.; Allentown (Lehigh County); Remote; USD 80,000 - 120,000; Full time

Job summary

3Core Systems Inc. is seeking 3-4 remote Java API developers to work primarily with the Micronaut framework. The role involves developing and optimizing APIs, requiring expertise in Java and a solid understanding of RESTful design. This is a 12-month contract position with opportunities for extension and quarterly travel to various locations.

Qualifications

• Proficient in Java API development with exposure to Micronaut or similar frameworks.
• Strong understanding of RESTful API design.
• Familiarity with debugging tools, mobile API security, and performance optimization.

Responsibilities

• Develop APIs using Java with a focus on RESTful design.
• Utilize Micronaut for optimized API performance.

Skills

Java API development

RESTful API design

Debugging tools

Mobile API security

Performance optimization

Tools

Micronaut Framework

Job description

Allentown, United States | Posted on 06/25/2025

Location: 90% Remote (quarterly travel - Louisville, KY; Allentown, PA; or Providence, RI)

Contract: 12 months (ability to extend)

Requirements:

• We need 3-4 native Java API developers. Here is what they are using: Micronaut Framework.
• I’m sure Java developers can learn Micronaut/Client's Java API framework. I was just calling out Micronaut as more of a nice-to-have skill.
• Proficient in Java API development with exposure to Micronaut or similar frameworks.
• Strong understanding of RESTful API design.
• Familiarity with debugging tools, mobile API security, and performance optimization.