Available — 35 hours per week

Sergei Alekseev

Senior Backend & Agentic Engineer · 15+ years

Backend engineer with 15 years of experience building robust, high-performance applications. Practices agentic engineering — orchestrating AI coding agents for architecture, implementation, and code review while maintaining full human oversight.

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About

With 15 years of extensive experience in backend development and a versatile skill set that includes frontend capabilities, I specialize in creating robust, high-performance applications. My expertise spans Python, Java, AWS, Docker, and various modern web technologies. I excel in backend logic development, web scraping, REST API development, performance optimization, database management, and process automation. I am passionate about researching, debugging, and enhancing code to achieve optimal performance and maintainability. Currently based in Istanbul (GMT+3), I am available for up to 35 hours per week, providing high-quality work to help achieve your business goals.

15+

Years experience

35

Hours / week

Istanbul

Location

9 AM - 9 PM GMT+3

Working hours

Projects

15 projects

Agentic Engineering Workflow

Agentic Engineer

Claude CodeCursorMCP ServersGitHub CopilotOpenAI API+3

Backend Infrastructure Enhancement with AWS

Python Specialist

PythonAWS ServerlessLinux

CQRS & Event Sourcing with Kafka and Clojure (Proof of Concept)

Developer

Apache KafkaClojureSwagger

ElasticSearch Image Search & Metadata Generation Platform

Lead Developer & Consultant

PythonElasticSearchOpenAI APINginxJavaScript+4

Fintech Backend Development (Fair Play)

Senior Backend Developer

PythonDjangoDjango Rest FrameworkCeleryGoogle Cloud Platform+4

Financial Analytics Dashboard with Flask

Backend Developer

PythonFlaskPytestDockerDocker Compose+7

Named Entity Recognition Chrome Extension

Full Stack Developer

PythonFlaskHTMLCSSSpaCy+5

Parking Lot Management System

Java Developer & Mentor

JavaREST APIAngularJSSQL ServerGit

Performance Optimization for Options Backtesting Tool

Python Consultant

PythonPandasMatplotlibNumPy

SOAP API Integration with ManageEngine ServiceDesk Plus

Developer & Consultant

PythonSOAPREST APIManageEngine ServiceDesk Plus

Twilio & WebSocket Integration for Automated Call Management

Lead Developer

PythonFlaskSQLiteTwilioTwiML+8

Unpaid Music — Distribution Platform for AI-Generated Music

Solo Full-Stack Developer

Next.js 16React 19TypeScriptCSS ModulesSupabase+5

Credit Product Backend for Fintech Startup (Upwardli)

Python Backend Developer

PythonDockerPostgreSQLDjangoDjango Rest Framework+1

Vehicle Maintenance Reporting System

Full Stack Developer

PythonFlaskMongoDBMongooseReact.js+4

Vibehackers.io — Community Platform for AI-Assisted Developers

Lead Full-Stack Developer

Next.js 15React 19TypeScriptTailwind CSSSupabase+10

Skills

Languages

Python (Flask, Django, DRF, Requests, SQLAlchemy, BeautifulSoup, Pytest)Java (Core Java, Dropwizard, Hibernate, REST, JUnit, Maven)Clojure

Web

FlaskDjangoDjango Rest FrameworkVue.jsReact.jsAngularJSJavaScriptTypeScriptHTMLCSSBootstrapjQueryClojurescript

Databases

PostgreSQLMySQLSQLiteMongoDBRedisElasticSearchAWS DynamoDBSQL ServerBigQueryLanceDBVector Databases

DevOps & Cloud

DockerDocker ComposeKubernetesAWSGCPNginxApacheLinuxGit

APIs & Integrations

Twilio APIOpenAI APISOAPREST APIManageEngine ServiceDesk PlusShopifyAPIebaysdkParamiko

AI / ML

Semantic SearchLarge Language Models (LLMs)Retrieval-Augmented Generation (RAG)Model FinetuningPrompt Engineering

Agentic Engineering

Claude CodeCursorGitHub CopilotMCP ServersContext EngineeringSpec-Driven DevelopmentMulti-Agent OrchestrationAI Code Review

Areas of interest

Backend logic development · AI agents · LLM-based integrations · Web scraping · Web applications · REST API development · Performance optimization · Console utilities · Database applications · Data mining · Agentic Engineering