Kefeng is available for hire

Kefeng Zhang

Verified Expert in Engineering

Algorithms Developer

Location

London, United Kingdom

Toptal Member Since

May 16, 2021

Kefeng is a back-end Java developer with more than 13 years of development experience. He is a certified Java developer with in-depth knowledge and hands-on experience using mainstream technologies on the JVM technology stack. Kefeng has been working for many world's largest banks, providing solutions for their mission-critical projects. With a strong mathematical background, he has worked closely with quantitative analysts and provided reliable IT solutions for their complex problems.

Back-end Back-end Development Java Unit Testing Java Concurrency Hibernate Spring Oracle Relational Databases JMS REST APIs Java 8 Microservices Spring Boot Java 11

Portfolio

HSBC

Java 8, Python 3, Back-end, Spring Boot, Apache Airflow, Apache Kafka

Credit Suisse

Java 11, Java 8, Spring Boot, Hibernate, Back-end, Amazon Web Services (AWS)...

BlackRock

Java 8, JMS, Oracle Database, Spring, Back-end, Oracle, Relational Databases...

Experience

Algorithms - 20 years Back-end - 13 years Java - 13 years Relational Databases - 12 years Oracle - 12 years RESTful Services - 10 years Microservices - 6 years Spring Boot - 5 years

Availability

Part-time

Preferred Environment

Java, Spring Boot, Java Concurrency, Oracle Database, Microservices, Amazon Web Services (AWS), Relational Databases, RESTful Services, Algorithms, Financial Markets

The most amazing...

...thing I've developed is a fixed-income product pricing system that handles requests in single-digit milliseconds. Made from scratch to production in six months.

Work Experience

Senior Software Developer

2021 - PRESENT

HSBC

Developed HSBC's new risk calculation aggregation system.
Replaced HSBC's legacy equity risk calculation system.
Improved and refactored some vital parts of the new system to improve performance.

Technologies: Java 8, Python 3, Back-end, Spring Boot, Apache Airflow, Apache Kafka

Senior Software Developer

2020 - 2021

Credit Suisse

Contributed to Credit Suisse’s next-generation risk calculation platform.
Developed and maintained the compiler of Credit Suisse's risk modeling language.
Developed the field-level encryption functionality of Credit Suisse's data modeling language that allows users to define and encrypt certain risk model fields.

Technologies: Java 11, Java 8, Spring Boot, Hibernate, Back-end, Amazon Web Services (AWS), Algorithms

Java Consultant

2019 - 2020

BlackRock

Developed an event-driven reporting system for a fund trading and attribution system which handles more than 30 different time-critical reporting types and is fully configurable on the fly without service interruption.
Developed and maintained the transfer agent subsystem for BlackRock's proprietary Aladdin system.
Refactored many legacy systems into a microservice architecture.

Technologies: Java 8, JMS, Oracle Database, Spring, Back-end, Oracle, Relational Databases, Microservices, RESTful Services, REST APIs, Hibernate, Amazon Web Services (AWS), Algorithms

Java Consultant

2016 - 2018

Morgan Stanley

Developed the scenario calculation engine that applies regulatory scenarios on the entire credit product positions of the bank.
Built a regulatory stress tests reporting system. The results are processed and reported to all major regulatory bodies, including CCAR, PRA, FDSF, and EVE.
Acted as one of the two founding developers of the system and helped the team expand from two to seven developers.

Technologies: Java 8, Oracle Database, Back-end, Oracle, Relational Databases, Algorithms

Senior Developer

2014 - 2016

Nomura

Developed several major components of a fixed income trading platform that provides 50 different high-availability and distributed web services to upstream front office trading systems.
Developed a high-availability, real-time, and load-balanced analytics system that handles incoming analytics requests within single-digit milliseconds. Completely rewritten a legacy system from scratch on my own. Made into production in five months.
Developed a client clearing subsystem, which allows the bank to act as a clearing bank for clearing houses.

Technologies: Java 8, Oracle Database, Microservices, Back-end, Oracle, Relational Databases, RESTful Services, REST APIs, Algorithms

Software Developer

2012 - 2014

Mimecast

Developed a big data archiving engine that supports data warehousing for user data stored on Dropbox and Box.
Participated in developing Mimecast's cloud-based data management engine, including Mimecast Personal Portal and Mimecast Large Data Transfer products.
Contributed to Mimecast's internal SDK development and external service API development.

Technologies: PostgreSQL, Microservices, Back-end, Relational Databases, Algorithms

Software Developer

2010 - 2011

Trafigura

Developed Trafigura’s in-house commodity trade capture system. The application server provides various services, including trade capturing, document generating (using Thunderhead), authentication (using LDAP), and reference data.
Served as the lead developer and service owner of the integration layer that seamlessly bridges the document store of the application server and the Alfresco content management system.
Developed the front end UI of the trade capture system using C# and WPF.

Technologies: Oracle Database, JMS, Back-end, Oracle, Relational Databases, REST APIs, RESTful Services, Hibernate, Algorithms

Software Design Engineer

2009 - 2010

Imagination Technologies

Developed and maintained the driver for the PowerVR graphics core, which provides hardware implementation of OpenGL ES.
Developed and maintained the driver for the PowerVR graphics core to provide a hardware implementation of OpenGL VG.
Served as the key developer and capability owner of the Symbian platform driver for the PowerVR graphics core.

Technologies: C++, Symbian, ARM Assembler

Technical Consultant

2007 - 2009

Symbian

Developed multimedia service components of Symbian OS, such as graphics engine, a phone camera driver, audio service, and video compressing service.
Provided technical consultancy services to engineers from the world-leading mobile phone manufacturers and help them integrate new devices with Symbian OS.
Released critical middleware integration to Symbian OS's global clients.

Technologies: C++, Symbian

Experience

Fixed Income Product Analytics System

A strategic analytic platform for bonds and derivative products pricing. Worked closely with the quantitative team of a bank and successfully delivered the service to production from scratch in six months. The service provides real-time, load-balanced, and high-availability quantitative analytic service for a wide range of downstream banking systems.

Regulatory Scenario Stress Testing System

A highly computation-intensive regulatory scenario calculation system is used for conducting various regulatory stress tests for single-name, basket, and index credit products of a bank.

The results are processed and reported to all major regulatory bodies, including CCAR (US), PRA (UK), FDSF (UK), and EVE (US). Worked closely with the risk management team and risk quant to understand their requirements and provide solutions in a timely fashion.

Transfer Agent for Fund Trading System

A transfer agent is a key component of a fund trading system. It allows unification and real time allocation of a fund. Unification is a vital step of fund trading. It allows a fund to be divided into small units and attribute to each fund owner. The transfer agent system I worked on effectively achieves this. It allowed my client to save millions of pounds in fees paid to a third-party transfer agent service provider.

Skills

Languages

Java, Java 8, Java 11, Python 3

Frameworks

Spring Boot, Hibernate, Spring

Libraries/APIs

JMS, REST APIs

Tools

IntelliJ IDEA, Java Concurrency, Apache Airflow

Paradigms

Microservices, Design Patterns, Unit Testing

Platforms

Oracle Database, JVM, Oracle, Linux, Amazon Web Services (AWS), Apache Kafka

Storage

Relational Databases, PostgreSQL

Other

Back-end, Back-end Development, Integration Testing, RESTful Services, Mathematical Programming, Financial Engineering, Fixed Income, Risk Models, Algorithms, Financial Markets, Quantitative Finance, Virtual Machines

Education

2002 - 2006

Ph.D. Degree in Computer Science

Robert Gordon University - Aberdeen, UK

2001 - 2002

Master's Degree in Advanced Computing

University of Bristol - Bristol, UK

1997 - 2001

Bachelor's Degree in Management Engineering

Sichuan University - Chengdu, China

Certifications

FEBRUARY 2021 - PRESENT

Oracle Database SQL Certified Associate

Oracle

APRIL 2015 - PRESENT

The CFA Institute Investment Foundations Certificate

CFA Institute

NOVEMBER 2009 - PRESENT

Sun Certified Java Programmer

Sun Microsystems

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