Sergei Malafeev, Developer in Moscow, Russia
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Sergei Malafeev

Verified Expert  in Engineering

Software Developer

Location
Moscow, Russia
Toptal Member Since
June 9, 2015

Sergei is an experienced full-stack Java developer with over ten 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. He worked with large code bases and solved performance and scaling issues. His skill set and disposition make him the perfect addition to any project.

DebuggingBack-endJavaSwingJava ConcurrencyLinuxObject-oriented Programming (OOP)SpringJakarta Server Pages (JSP)Apache MavenUnit TestingJUnitRelational DatabasesDatabasesJEEJavaFX

Portfolio

In Class Today, Inc
Java, SQL, Amazon Web Services (AWS), GraphQL, React, PostgreSQL, Databases
Canotic Inc.
Java, Amazon Web Services (AWS), Docker, Gradle, Distributed Systems, Pub/Sub...
LightStep Inc (via Toptal)
Java, Scala, Apache Kafka, MongoDB, Apache Cassandra, Spring, RabbitMQ, JDBC...

Experience

Java - 12 yearsJava Concurrency - 12 yearsJavaScript - 8 yearsJAX-RS - 6 yearsSpring MVC - 6 yearsHibernate - 6 yearsSpring Boot - 6 yearsJPA - 6 years

Availability

Full-time

Preferred Environment

Git, IntelliJ IDEA, MacOS

The most amazing...

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

Work Experience

Senior Full-stack Developer

2022 - 2022
In Class Today, Inc
  • Implemented back-end features related to data aggregation, search, and presentation.
  • Worked within an existing codebase and established a tech stack.
  • Delivered a feature roadmap for July 2022 and beyond.
Technologies: Java, SQL, Amazon Web Services (AWS), GraphQL, React, PostgreSQL, Databases

Expert Back-end Java Developer

2021 - 2022
Canotic Inc.
  • 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 a cache.
  • Developed interaction with a machine learning engine from the Java back end.
Technologies: Java, Amazon Web Services (AWS), Docker, Gradle, Distributed Systems, Pub/Sub, Redshift, Amazon Simple Queue Service (SQS), Redis, Spring, Spring Boot, gRPC, Hibernate, JPA, PostgreSQL, SaaS, Integration, Relational Databases, Integration Testing, Java 11, GitOps, Machine Learning, Databases

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), Relational Databases, Databases

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, Freelancing, Spring Security, SQL, Apache Tomcat, Git, Spring JDBC, JUnit, Spring Data JPA, REST APIs, AWS SDK, DB, Linux, Java Concurrency, MySQL, Back-end, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, Apache Maven, DevOps, REST, Unit Testing, Spring, RESTful Development, Mockito, Data Structures, Object-oriented Programming (OOP), SaaS, Integration, Relational Databases, Integration Testing, Databases

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, Freelancing, Amazon S3 (AWS S3), jQuery, CSS, SQL, Git, Spring JDBC, Spring Data JPA, Java EE, REST APIs, JEE, AWS SDK, DB, Jakarta Server Pages (JSP), Linux, Java Concurrency, PostgreSQL, Back-end, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, Apache Maven, DevOps, REST, Unit Testing, Spring, Full-stack, RESTful Development, Mockito, Data Structures, Object-oriented Programming (OOP), Relational Databases, Integration Testing, Machine Learning, Databases

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, Freelancing, Agile Software Development, Git, JUnit, Subversion (SVN), AWS SDK, Linux, Java Concurrency, Back-end, Concurrent Programming, IntelliJ IDEA, APIs, Debugging, Apache Maven, Unit Testing, Jira, Mockito, Data Structures, Object-oriented Programming (OOP), Relational Databases, Integration Testing

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, Freelancing, SQL, Git, Spring JDBC, XML, JUnit, Spring Data JPA, DB, Swing, Linux, Java Concurrency, Spring, JavaFX, Concurrent Programming, IntelliJ IDEA, JDBC, Debugging, Apache Maven, Unit Testing, Mockito, Data Structures, Object-oriented Programming (OOP), Relational Databases

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, Freelancing, MongoDB, Amazon DynamoDB, Amazon S3 (AWS S3), JMS, NoSQL, SQL, Git, Spring JDBC, SOAP, AWS SDK, DB, Linux, Java Concurrency, IBM Db2, Oracle, PostgreSQL, Microsoft SQL Server, MySQL, RabbitMQ, Spring, Back-end, REST APIs, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, Oracle Database, XML, Apache Maven, REST, Unit Testing, RESTful Development, Data Structures, Object-oriented Programming (OOP), Relational Databases, Databases

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, Jakarta Server Pages (JSP), Linux, Java Concurrency, MySQL, Cassandra, RabbitMQ, JAX-RS, Spring, Back-end, Microservices, HTML, Concurrent Programming, IntelliJ IDEA, JDBC, APIs, Debugging, QA Automation, Apache Maven, REST, Unit Testing, Full-stack, RESTful Development, Jira, ActiveMQ, TestNG, Servlet, Apache CXF, Data Structures, Object-oriented Programming (OOP), Relational Databases, Integration Testing, Databases

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, Apache Maven, REST, Unit Testing, Full-stack, RESTful Development, Jira, PrimeFaces, Servlet, JSF, Data Structures, Object-oriented Programming (OOP), Relational Databases, Databases

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, Apache Maven, Unit Testing, Data Structures, Object-oriented Programming (OOP)

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.

Languages

Java, HTML, SQL, HTML5, Java 11, Python 3, Kotlin, CSS, Python, Groovy, Scala, JavaScript, XML, Go, GraphQL

Frameworks

Spring, Jakarta Server Pages (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

Apache Maven, Jira, Java Concurrency, Subversion (SVN), Servlet, IntelliJ IDEA, RabbitMQ, Git, AWS SDK, Apache Tomcat, ActiveMQ, Gradle, Jetty, Amazon Simple Queue Service (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, Kubernetes, MacOS

Storage

Spring Data JPA, DB, MySQL, Spring Data, Relational Databases, Databases, Redis, Amazon S3 (AWS S3), Amazon DynamoDB, NoSQL, MongoDB, Cassandra, PostgreSQL, Microsoft SQL Server, IBM Db2, Hazelcast, Memcached, Redshift

Other

Back-end, APIs, Debugging, Freelancing, Data Structures, Integration Testing, Full-stack, Spring Cloud, SOAP, SaaS, Integration, Apache Cassandra, QA Automation, Distributed Systems, Pub/Sub, GitOps, Machine Learning

2000 - 2006

Master's Degree in Physics

Nizhny Novgorod State University - Nizhny Novgorod, Russia

NOVEMBER 2020 - PRESENT

Kotlin for Java Developers

Coursera

JUNE 2020 - JUNE 2023

AWS Certified Cloud Practitioner

Amazon Web Services (AWS)

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