Back End Developer (Java)

HashOptima; Hong Kong; On-site; HKD 420,000 - 780,000; Full time

Job summary

HashOptima seeks a Backend Java/Python Developer to join its core team in Hong Kong. You will work on greenfield projects for large-scale trading and quotation systems, handling the full software development life cycle from requirements to deployment.

You will deliver low-latency, high-throughput production code and collaborate with Research/Quant to improve pricing and hedging models, while mentoring juniors and optimizing infrastructure for scale and reliability.

Qualifications

• 2+ years in full lifecycle Java/Python app development.
• Strong problem solving and ownership mindset.
• Solid knowledge of software design, architecture and systems integration.
• Experience with multi-threading, event processing and REST APIs.
• Hands-on with Spring/Spring Boot, MyBatis, MySQL, Redis and Kafka.
• Proficient Python for trading, hedging and risk management systems.
• Experience in high availability, high throughput, low latency environments.
• Familiar with AI coding agents and agent-driven workflows is a plus.

Responsibilities

• Participate in all stages of the software development life cycle.
• Deliver high-quality production code for low-latency trading systems.
• Collaborate with Research/Quant to enhance trading models (pricing/hedging).
• Liaise with trading and product teams to develop trading products.
• Improve trading system infra to handle large-scale quotes and orders.
• Implement risk management and position-monitoring tools.
• Identify bottlenecks and drive root-cause fixes.
• Mentor juniors and lead design/code reviews.
• Be available during flexible hours for production emergencies.
• Leverage AI coding agents to plan, design, test and review code.

Skills

Java

Python

Full lifecycle

Low latency

High throughput

Problem solving

Ownership mindset

Design patterns

Multi-threading

REST

Spring / Spring Boot

MyBatis

MySQL

Redis

Kafka

Cloud deployment

AI coding agents

Education

Bachelor's degree in CS/Engineering/Math

Tools

Claude Code

Cursor

Copilot

Jira

Confluence

GitHub

Job description

About company: https://www.hashoptima.com/

We are looking for a Backend Java/Python Developer to join our core development team. The successful candidate will participate in greenfield projects building large-scale trading and quotation systems. Daily tasks include, but are not limited to:

Responsibilities

• Engage in all stages of the software development life cycle: establishing requirements, designing, writing code, testing, and deployment.
• Deliver high-quality production code for low-latency, high-throughput trading systems.
• Collaborate with the Research/Quant team to build and enhance trading and quotation models (e.g. pricing, hedging, delta-residual models).
• Liaise with the trading and product teams to develop new trading products and improve existing ones.
• Establish and improve trading system infrastructure to handle large-scale positions, quotes, and orders.
• Implement and improve risk management and position-monitoring tools.
• Identify system bottlenecks and bugs and drive solutions to root causes.
• Mentor junior developers and lead design and code reviews.
• Be available during flexible hours to address production emergencies.
• Leverage AI coding agents (e.g. Claude Code) as a core part of the daily workflow — including project planning and Jira/ticket management, generating and reviewing technical designs, writing and refactoring production code, authoring and automating tests, and performing code/security reviews. Candidates are expected to be proficient in prompting, orchestrating, and validating agent output, and to continuously improve team-level agent tooling (skills, hooks, MCP integrations, CI automations).

Requirements

• 2+ years of experience in the full lifecycle of Java/Python application development.
• Excellent problem-solving capabilities and strong ownership mindset.
• Strong understanding of software design, architecture, development, and system integration.
• Solid knowledge of event processing models, multi-threading, enterprise integration patterns, web services, and REST.
• Solid knowledge of backend technologies such as Spring / Spring Boot, MyBatis, MySQL, Redis, Kafka, and cloud-native deployment.
• Working proficiency in Python, with hands-on experience building trading, hedging, and risk management systems.
• Experience with high availability, high throughput, low latency systems.
• Hands-on experience using AI coding agents (Claude Code, Cursor, Copilot, or similar) to ship production code. Familiarity with agent-driven workflows — writing CLAUDE.md / rules files, building custom skills or slash commands, integrating MCP servers (Jira/Confluence/GitHub), and designing prompts and review loops that keep agent output reliable — is strongly preferred.
• Experience with algorithmic trading systems, investment banks, hedge funds, trading firms, brokerages, or crypto exchanges is a plus.
• Understanding of derivatives products such as options (pricing, Greeks, hedging) is a plus.
• Flexibility with location, with preference for candidates in Asian time zones.
• A degree in Computer Science, Engineering, Mathematics, or a related field is preferred.
• Contributions to internal developer tooling, agent skills, or AI-assisted engineering productivity is a plus.