Sergei Malafeev, Software Developer in Singapore, Singapore
Sergei Malafeev

Software Developer in Singapore, Singapore

Member since June 9, 2015
Sergei is an experienced full-stack Java developer with more than 10 years in the IT industry. He has strong Java programming skills and experience in different frameworks and databases. He develops back-end, front-end, and desktop applications. His skill set and disposition make him the perfect addition to any project.
Sergei is now available for hire

Portfolio

Experience

Location

Singapore, Singapore

Availability

Part-time

Preferred Environment

Git, Linux, IntelliJ IDEA

The most amazing...

...thing I've developed is a Twitter-like messaging application for internal usage.

Employment

  • Expert Back-end Java Developer

    2021 - 2022
    Canotic Inc. (via Toptal)
    • Divided Java REST service into two microservices to improve performance.
    • Migrated the database into two databases to be used by each microservice.
    • Created different performance and scalability optimizations such as introducing a message queue, adding a read-only database, and adding cache.
    Technologies: Java, Amazon Web Services (AWS), Docker, Gradle, AWS, Distributed Systems, Pub/Sub, Redshift, Amazon SQS, Redis, Spring, Spring Boot, gRPC, Hibernate, JPA, PostgreSQL, SaaS, Integration
  • Java Open-source Programming

    2017 - 2021
    LightStep Inc (via Toptal)
    • Developed open-source OpenTracing instrumentations for different programming languages and frameworks: Java, Scala, and Go.
    • Contributed to OpenTelemetry projects for Java: APIs and auto instrumentation.
    • Developed a Java agent for OpenTracing auto instrumentation.
    Technologies: Java, Scala, Apache Kafka, MongoDB, Apache Cassandra, Spring, RabbitMQ, JDBC, Akka, AWS SDK, Mockito, Functional Programming, TestNG, gRPC, Protobuf, Data Structures, Object-oriented Programming (OOP)
  • Java Developer

    2016 - 2021
    Sid's Software (via Toptal)
    • Developed a REST API for a medical questionnaire application using Spring Boot and MySQL and deployed it to AWS.
    • Developed an architecture of the application from scratch.
    • Supported deployment and maintenance of the application on AWS.
    Technologies: Amazon Web Services (AWS), Spring MVC, Hibernate, Java, Spring Boot, JPA, Redis, Freelance, Spring Security, SQL, Apache Tomcat, Git, Spring JDBC, JUnit, Spring Data JPA, REST APIs, AWS SDK, DB, Linux, Java Concurrency, AWS, MySQL, Back-end, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, Maven, DevOps, REST, Unit Testing, Spring, RESTful Development, RESTful APIs, Mockito, Data Structures, Object-oriented Programming (OOP), SaaS, Integration
  • Java Developer

    2018 - 2019
    Vizadata, LLC (via Toptal)
    • Developed a Java-based web application for a machine learning back end.
    • Troubleshot the application issues on AWS (EC2 configuration and Load Balancing).
    • Developed the front end of the application using Bootstrap and jQuery.
    Technologies: Amazon Web Services (AWS), Hibernate, JavaScript, Java, Spring Data, JPA, HTML5, Freelance, AWS S3, jQuery, CSS, SQL, Git, Spring JDBC, Spring Data JPA, Java EE, REST APIs, JEE, AWS SDK, DB, JSP, Linux, Java Concurrency, AWS, PostgreSQL, Back-end, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, Maven, DevOps, REST, Unit Testing, Spring, Full-stack, RESTful Development, RESTful APIs, Mockito, Data Structures, Object-oriented Programming (OOP)
  • Senior Java Developer

    2018 - 2019
    Harman International - DV (via Toptal)
    • Developed a back end for Bitbucket and Bamboo plugins.
    • Dove deeply into the source code of Atlassian products.
    • Implemented robust solution to concurrently run Git commands in Java processes.
    Technologies: Amazon Web Services (AWS), Java, Freelance, Agile Software Development, Git, JUnit, Subversion (SVN), AWS SDK, Linux, Java Concurrency, AWS, Back-end, Concurrent Programming, IntelliJ IDEA, APIs, Debugging, Maven, Unit Testing, Jira, Mockito, Data Structures, Object-oriented Programming (OOP)
  • Java Developer

    2016 - 2018
    Quantum Trade Solutions (via Toptal)
    • Developed a trading journal desktop application based on JavaFX.
    • Developed an open-source JavaFX component library.
    • Analyzed the user's workflows to implement application features.
    Technologies: Hibernate, Java, Spring Data, JPA, Freelance, SQL, Git, Spring JDBC, XML, JUnit, Spring Data JPA, DB, Swing, Linux, Java Concurrency, Spring, JavaFX, Concurrent Programming, IntelliJ IDEA, JDBC, Debugging, Maven, Unit Testing, Mockito, Data Structures, Object-oriented Programming (OOP)
  • Java Developer

    2015 - 2016
    VineLight (via Toptal)
    • Developed a common REST interface for four databases.
    • Developed a procedure for an application auto-upgrade.
    • Developed a watcher for changes in the MS SQL database.
    • Added the application integration with AWS DynamoDB and S3.
    Technologies: Amazon Web Services (AWS), Spring MVC, Hibernate, JavaScript, Java, Spring Boot, Freelance, MongoDB, AWS DynamoDB, AWS S3, JMS, NoSQL, SQL, Git, Spring JDBC, SOAP, AWS SDK, DB, Linux, Java Concurrency, IBM Db2, Oracle, PostgreSQL, Microsoft SQL Server, MySQL, AWS, RabbitMQ, Spring, Back-end, REST APIs, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, Oracle Database, XML transformation, XML, Maven, REST, Unit Testing, RESTful APIs, RESTful Development, Data Structures, Object-oriented Programming (OOP)
  • Senior Java Developer

    2013 - 2016
    IPsoft
    • Developed a REST API based on JAX-RS specification.
    • Developed front-end features based on the Ext JS framework.
    • Developed a Twitter-like messaging application for the company usage.
    • Developed an HTML5 terminal to connect to remote hosts.
    • Developed a distributed, microservices-based, multi-task application for people management, data processing, monitoring, etc.
    Technologies: Spring MVC, Hibernate, JavaScript, Java, Spring Boot, JPA, Jetty, HTML5, Spring Integration, Ext JS, Spring Security, jQuery, JMS, NoSQL, Python, CSS, Agile Software Development, Python 3, SQL, Apache Tomcat, Git, Spring JDBC, JUnit, Docker, Spring Data JPA, REST APIs, Hazelcast, DB, JSP, Linux, Java Concurrency, MySQL, Cassandra, RabbitMQ, JAX-RS, Spring, Back-end, Microservices, HTML, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, QA Automation, Maven, REST, Unit Testing, Full-stack, RESTful Development, RESTful APIs, Jira, ActiveMQ, TestNG, Servlet, Apache CXF, Data Structures, Object-oriented Programming (OOP)
  • Software Developer

    2011 - 2013
    TomTom
    • Developed monitoring and administration tools for QuickBuild, Perforce, and Protex.
    • Developed an Eclipse plugin for importing projects and IDE customization.
    • Developed a pipeline plugin for QuickBuild, a continuous integration tool.
    • Migrated Java-based projects to Scala using the Play framework.
    • Migrated the build system from Ant to Maven for the entire department.
    Technologies: Spring MVC, Hibernate, JavaScript, Java, Play 2, HTML5, Groovy, jQuery, JMS, NoSQL, Python, CSS, Agile Software Development, Python 3, Apache Tomcat, Spring JDBC, Java EE, REST APIs, JEE, DB, Swing, Linux, Java Concurrency, Scala, Spring, Back-end, HTML, Concurrent Programming, JDBC, APIs, Debugging, Maven, REST, Unit Testing, Full-stack, RESTful Development, RESTful APIs, Jira, PrimeFaces, Servlet, JSF, Data Structures, Object-oriented Programming (OOP)
  • Software Developer

    2008 - 2011
    Intel
    • Developed a software update manager for applications on Linux.
    • Developed a graphical tool for cluster monitoring.
    • Developed tools for Intel® MPI configuration and task execution.
    Technologies: Java, Python, Python 3, XML, SOAP, Subversion (SVN), DB, Swing, Linux, Java Concurrency, Concurrent Programming, Debugging, QA Automation, Maven, Unit Testing, Data Structures, Object-oriented Programming (OOP)

Experience

  • OpenTelemetry for Java
    https://github.com/open-telemetry

    Contributed to different projects of OpenTelemetry for Java, like:
    • APIs.
    • Auto Instrumentation.
    • Customised vendor Java agent for OpenTelemetry auto instrumentation.

    Participated in weekly OpenTelemetry auto instrumentation meetings to discuss different aspects of project development.

  • OpenTracing Instrumentations
    https://github.com/opentracing-contrib

    Developed open-source OpenTracing instrumentations for different programming languages and frameworks:
    • Java: JMS, Kafka, Mongo, Cassandra, RabbitMQ, JDBC, and RxJava.
    • Scala: Akka and Finagle.
    • Go: AWS SDK.

    Also took an active part in the development of SpecialAgent, a Java agent for automatic instrumentation of applications.

  • SSH client
    https://github.com/malafeev/JFTClient

    Developed a graphical SSH client for Linux and OS X operating systems. Initially, the client was based on Swing but then ported to JavaFX and Spring. I also added a remote terminal to run commands on a remote host.

Skills

  • Languages

    Java, HTML, SQL, HTML5, Python 3, Kotlin, CSS, Python, Groovy, Scala, JavaScript, XML, Go
  • Frameworks

    Spring, JSP, JUnit, Hibernate, Spring JDBC, Swing, Mockito, JPA, Spring Boot, Spring MVC, Spring Integration, TestNG, Spring Security, Ext JS, Spock Framework, Angular, gRPC, Play 2, AngularJS, PrimeFaces, JSF, Apache CXF, Akka
  • Libraries/APIs

    REST APIs, JAX-RS, JDBC, RxJava, JMS, jQuery, React, Protobuf
  • Tools

    Maven, Jira, Java Concurrency, Subversion (SVN), Servlet, IntelliJ IDEA, RabbitMQ, Git, AWS SDK, Apache Tomcat, ActiveMQ, Gradle, Jetty, Amazon SQS
  • Paradigms

    REST, Unit Testing, RESTful Development, Concurrent Programming, Object-oriented Programming (OOP), Microservices, DevOps, Agile Software Development, Functional Programming
  • Platforms

    Docker, JEE, Java EE, JavaFX, Linux, Amazon Web Services (AWS), Oracle, Oracle Database, Apache Kafka
  • Storage

    Spring Data JPA, DB, Spring Data, Redis, MySQL, AWS S3, AWS DynamoDB, NoSQL, MongoDB, Cassandra, PostgreSQL, Microsoft SQL Server, IBM Db2, Hazelcast, Memcached, Redshift
  • Other

    Back-end, APIs, Debugging, RESTful APIs, Freelance, Data Structures, AWS, Full-stack, Spring Cloud, SOAP, SaaS, Integration, Apache Cassandra, XML transformation, QA Automation, Distributed Systems, Pub/Sub

Education

  • Master's Degree in Physics
    2000 - 2006
    Nizhniy Novgorod State University - Nizhniy Novgorod, Russia

Certifications

  • Kotlin for Java Developers
    NOVEMBER 2020 - PRESENT
    Coursera
  • AWS Certified Cloud Practitioner
    JUNE 2020 - JUNE 2023
    Amazon Web Services (AWS)

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