Position: Node.js Developer
Category: Node.js
English level: upper
Years of experience: 8


Experienced software developer with information security and DevOps skills. Experience in design and development from desktop applications to large client-server distributed systems. Expertise in asynchronous and concurrent programming. Profiling and application optimization skills. Able to work independently as well as work in a team.

History:
Senior Software Engineer at Tatum (Feb 22 - Feb 23)

Worked on a Tatum blockchain integration platform:
1. Covered 40% of the API with e2e tests (~23000 tests). 
2. Reduced API request execution time by 21% by optimizing NestJS injections
3. Refactored legacy code from Tatum SDK v1
4. Participated in the development of blockchain indexers with ERC20/721/1155 transaction detection and calculation of actual balances
5. Implemented API for smart contract calls on evm-based blockchains and Solana

Technology Stack:
TypeScript, JavaScript, NodeJS
NestJS, Jest, Nx
MongoDB Atlas, Vault, Redis
Google Spanner, BigQuery, Pub/Sub
Blockchains: BTC, ETH, SOL, POLYGON, CELO...

Senior Java/Kotlin Developer at FinTech Startup (Jan 21 - Feb 22)
Involved in the development of several cryptocurrency projects:
1. Platform for OTC trading
2. Service for accepting and processing payments in cryptocurrency for third-party merchants

Technology Stack:
Kotlin,  Spring (Boot, Security, Data, Cache, AMQP, OAuth, WebFlux, Test)
GraphQL, REST, gRPC
PostgreSQL, Redis, HashiCorp Vault
RabbitMQ
Gradle, GitLab CI, GCP
Docker, Testcontainers
Blockchains: Bitcoin, ETH, Tron, BSC

Senior Java Developer at MCLab (Jan 14 - Dec 20)
Worked at various Minecraft server projects

1. Built an ecosystem for entire game server, the in-game economy, social services such as friend list, parties and guilds, various cross-server integrations and more
2. Developed a sharding system for players, which made it possible to serve an unlimited number of players simultaneously instead of ~ 120 per server
3. Deployed self-hosted Kubernetes to provide horizontal scalability of game servers depending on the current load
Increased the performance of the original game core by ~ 35% by optimizing hot methods
4. Developed the entire backend for the website integrated with the external payment system

Technology Stack:
Core: Java 8, Netty, JDBC
SQL: PostgreSQL
NoSQL: Redis, MongoDB
Microservices: Spring (Boot, Security, Data, Cache, State Machine, JWT)
Docker, Kubernetes, Agones
Maven, Gradle, GitLab CI
Libraries: Guava, Caffeine, Gson, HikariCP