Alex Gridnev, Developer in Limassol, Cyprus
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Alex Gridnev

Verified Expert  in Engineering

Software Engineer and Developer

Limassol, Cyprus
Toptal Member Since
October 25, 2022

Alex is a systems architect and software engineer with 11+ years of back-end and full-stack experience designing, implementing, and continuously deploying large-scale, low-latency projects capable of processing 100,000+ messages per second for platforms serving 500,000+ customers. Alex has launched revenue-generating products (up to several million dollars annually) from the ground up and helped a company get accepted into a top-tier startup accelerator in the US.


TypeScript, React, Cypress, HTML, CSS, SCSS, JavaScript, Kotlin, Amazon RDS...
Scala, TypeScript, Solidity, React, Amazon Web Services (AWS), Apache Cassandra...
FxPro Group
Java, Spring IoC, RESTful Microservices, Test-driven Development (TDD)...




Preferred Environment

IntelliJ IDEA, WebStorm, Java, TypeScript, Solidity, Scala, Kotlin, React, JavaScript

The most amazing...

...thing I've built is a distributed B2B Growegy platform from scratch—the company grew from 0 to 2,000 paying business customers and earned first revenue.

Work Experience

Software Architect

2020 - PRESENT
  • Created a distributed B2B Growegy platform (back and front end) from scratch, allowing the company to grow from 0 to 2,000 paying business customers and earn first revenue.
  • Slashed business customer onboarding time from 30 to 1 minute through an internal CRM and automated profile provisioning, resulting in a 50% reduction in the time spent by the customer support department on onboarding tasks.
  • Cut down QA verification time by 40% by ensuring end-to-end test coverage for both front- and back-end business scenarios and creating a subset of tests simulating real users' behavior in pre-production environments.
  • Led the system architecture and engineering processes, resulting in regular releases and predictable deployment of new features by defining the strategy with executives and executing the delivery.
Technologies: TypeScript, React, Cypress, HTML, CSS, SCSS, JavaScript, Kotlin, Amazon RDS, Amazon Simple Email Service (SES), Amazon Web Services (AWS), PostgreSQL, Terraform, Agile, Test-driven Development (TDD), IT Project Management, Scrum, Jira, Microservices

Back-end Scala Engineer

2018 - 2022
  • Created an architecture and led a B2B pivot, resulting in the company's new revenue stream that allowed business customers to organize online group fitness engagements for their employees during the COVID-19 pandemic.
  • Elevated user retention by 15% through the creation of a user achievement system. This strategic implementation, featuring personalized leaderboards and analytics showcasing individual progress, effectively incentivized consistent system usage.
  • Achieved a 20% acceleration in development speed by migrating from Cassandra DB to PostgreSQL. This optimization was realized by implementing diverse indexes, enabling the team to replace complex code with streamlined SQL queries.
  • Accelerated crucial business flows by 8-10x by introducing batch updates into the PostgreSQL DB and parallel processing in back-end services.
  • Delivered 100+ business features that increased customer satisfaction and retention by conceptualizing, implementing, and releasing them—many of which were based on my proposals.
Technologies: Scala, TypeScript, Solidity, React, Amazon Web Services (AWS), Apache Cassandra, Redis, Akka, Functional Programming, Test-driven Development (TDD), Scrum, Microservices, Relational Databases

Lead Full-stack Engineer

2014 - 2018
FxPro Group
  • Revolutionized system performance, reducing custom report generation time from 30-40 to 3-5 minutes—accomplished through a redesign and expanded scaling of the distributed system, empowering the biz dev to validate ideas with heightened efficiency.
  • Built the integration of an existing trading exchange platform with the Ethereum blockchain.
  • Achieved tens of thousands of annual savings by seamlessly transitioning trading exchange services from Oracle DB to PostgreSQL DB. Additionally, addressed missing functionality by implementing cost-effective, custom, in-house solutions.
Technologies: Java, Spring IoC, RESTful Microservices, Test-driven Development (TDD), TypeScript, JavaScript, React, Behavior-driven Development (BDD), Solidity, Ganache CLI

.NET Software Engineer

2012 - 2014
Spotware Systems
  • Reduced traffic between the front-end desktop app and the back-end server by 40% by migrating the front-end app from text to binary protocol using Google Protocol Buffers.
  • Increased customer revenue by 15% by developing and evolving an admin application for a trading platform that detected anomalies, helped prevent abuse, and adjusted system parameters based on market conditions.
  • Oversaw a testing and releasing process for applications.
Technologies: .NET, C#.NET, Windows Presentation Foundation (WPF), ASP.NET, Test-driven Development (TDD)

Growegy Web App
Web-based martech software as a service (SaaS), including project management and analytic tools. I created and delivered a Growegy web platform allowing the company to onboard first customers and get first revenue. Also, I defined architecture and engineering processes, worked with executives on a strategy, and executed its delivery. I managed a team of three to six members and supervised junior engineers. Finally, I implemented a front-end side from scratch and defined and implemented end-to-end testing approaches.

Messenger and Fitness App for Mobile Devices
Initially, it had been a secured messenger with Ethereum blockchain integration that was later forked and transformed into an online fitness mobile app, Tonus. I mostly worked on back-end and blockchain parts.

I led the development of many business features, including gathering requirements, defining the architecture, and releasing the product. While researching throughput issues, I discovered the suboptimal ones, speeding up the slowest user queries by eight to ten times. Finally, I finished a massive project migration from Cassandra to PostgreSQL with a team of three members. It simplified and helped a back-end team speed up their development process significantly.
2006 - 2011

Master's Degree in Informatics and Applied Mathematics

National University of Science and Technology MISiS - Moscow, Russia


Ethereum and Solidity: The Complete Developer's Guide



Advanced Solidity: Understanding and Optimizing Gas Costs



React, Node.js


IntelliJ IDEA, WebStorm, Amazon Simple Email Service (SES), Terraform, Ganache CLI, Ganache, Jira


Java, TypeScript, Scala, JavaScript, Solidity, Kotlin, HTML, CSS, SCSS, C#.NET


Relational Databases, PostgreSQL, Databases, Redis, Cassandra


Test-driven Development (TDD), Object-oriented Programming (OOP), Functional Programming, Behavior-driven Development (BDD), Agile, Scrum, Microservices


Akka, Spring IoC, Spring, Cypress, .NET, Windows Presentation Foundation (WPF), ASP.NET, Hardhat


Amazon Web Services (AWS)


App Infrastructure, IT Management, CTO, Algorithms, Data Structures, Amazon RDS, Apache Cassandra, RESTful Microservices, IT Project Management

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