Senior Staff Engineer- Java & Kotlin

ApTask; Jersey City (NJ); Hybrid; USD 140,000 - 190,000; Full time

Job summary

ApTask is seeking a Senior Java/Kotlin Engineer to upgrade legacy trading systems to a cloud-native, event-driven architecture while ensuring high performance, data integrity, and stability in live environments.

The role requires hands-on Java and Kotlin development, experience with event-driven patterns, and strong TDD/CI/CD practices. The position operates in a hybrid model (3 days on-site) in a high-demand financial tech context.

Qualifications

• Bachelor's degree in Computer Science or related field.
• Strong Java expertise with Kotlin willingness to learn.
• Experience with event-driven messaging and distributed systems.
• Proficient in CI/CD and TDD practices.
• Ability to modernize legacy systems while maintaining production stability.

Responsibilities

• Develop and modernize enterprise trading systems using Java and Kotlin.
• Design event-driven applications using messaging and event-sourcing patterns.
• Implement TDD, automated testing, and CI/CD practices.
• Modernize legacy systems while ensuring zero-downtime releases.
• Collaborate with stakeholders and engineering teams to deliver scalable solutions.
• Leverage AI-assisted development tools for code analysis and testing.

Skills

Java

Kotlin

Event-driven

TDD

CI/CD

Production autonomy

Education

Bachelor's degree in Computer Science

Tools

Kafka

MongoDB

SQL Server

T-SQL

Kubernetes/OpenShift

OpenTelemetry

ELK

Grafana

Job description

We are seeking a Senior Java/Kotlin Engineer. The role involves upgrading legacy trading systems to event-driven, cloud-native architecture while ensuring high performance, data integrity, and stability in a live production environment.

Work Model: Hybrid (3 days/week on-site)

Tech Stack: Java & Kotlin (must-have)

Tech Stack: Java & Kotlin (must-have)

Key Responsibilities:

• Develop and modernize enterprise trading and post-trade systems using Java and Kotlin.
• Design event-driven applications using messaging and event-sourcing patterns.
• Implement Test-Driven Development (TDD), automated testing, and CI/CD practices.
• Modernize legacy systems while maintaining production stability and enabling zero-downtime releases.
• Collaborate with business stakeholders and engineering teams to deliver scalable solutions.
• Leverage AI-assisted development tools for code analysis, testing, and refactoring.

Required Qualifications:

• Strong Java expertise, with Kotlin experience or willingness to learn.
• Hands-on experience with event-driven architecture, messaging, and distributed systems.
• Strong TDD practices and experience with CI/CD and iterative delivery.
• Proven ability to modernize complex legacy systems and work independently in production environments.
• Bachelor's degree in Computer Science or a related field.

Preferred Skills:

• Experience in Prime Brokerage, Equity Swaps, or Cash Equities.
• Strong SQL Server, T-SQL, Kafka, and MongoDB skills.
• Familiarity with Kubernetes/OpenShift, cloud-native technologies, and monitoring tools such as OpenTelemetry, ELK, and Grafana.
• Knowledge of corporate actions, regulatory reporting, and risk/valuation systems.
• Experience using AI-assisted and agentic development tools.