Alex Kosarevsky

Full-Stack / Product Analytics Engineer

Tech: Django, DRF, FastAPI, Celery, PyTest, React, Playwright, GCP, Neon (Postgres), RabbitMQ, Sentry, Amplitude, Cube Cloud, Metabase, Better Stack, LaunchDarkly, OpenTelemetry, GitHub Actions, CI/CD, Docker, Stripe, Stytch, GTM Responsibility: - Owned end-to-end growth analytics + product instrumentation: designed event taxonomy, implemented tracking, validated data quality, and delivered funnel + KPI dashboards for leadership (conversion, retention, LTV, cohort views) - Built and iterated funnels & experiments (A/B tests): defined hypotheses, implemented variants behind feature flags, analyzed drop-offs, and shipped improvements based on experiment results - Implemented a reliable event pipeline: deduplication, consistent naming, backfilling patterns, and monitoring to prevent broken/duplicate tracking. - Developed core frontend features in React, collaborating with product/ops to ship fast business features, use Figma with MCP a lot. - Created an anomaly detection & alerting system for product + data pipelines: detectors for event spikes/ drops, failures, duplicates integrated with monitoring systems and actionable alerts - Strengthened production reliability with Sentry + OpenTelemetry + Better Stack: tracing critical flows, improving error triage, and adding runbooks/alerts for recurring incidents. - Improved delivery speed and safety via CI/CD, automated testing (PyTest/Playwright), making releases repeatable and reducing regressions.

• Owned end-to-end growth analytics + product instrumentation: designed event taxonomy, implemented tracking, validated data quality, and delivered funnel + KPI dashboards for leadership (conversion, retention, LTV, cohort views)
• Built and iterated funnels & experiments (A/B tests): defined hypotheses, implemented variants behind feature flags, analyzed drop-offs, and shipped improvements based on experiment results
• Implemented a reliable event pipeline: deduplication, consistent naming, backfilling patterns, and monitoring to prevent broken/duplicate tracking
• Developed core frontend features in React, collaborating with product/ops to ship fast business features
• Created an anomaly detection & alerting system for product + data pipelines
• Strengthened production reliability with Sentry + OpenTelemetry + Better Stack
• Improved delivery speed and safety via CI/CD and automated testing

Senior Full Stack Developer

Under NDA Tech: django, DRF, Celery, Kafka,FastAPI, Web3, Tron API, AWS (EC2, S3, ECS, ECR, Amplify, Rabbit, Redis, Load Balancers), WebSockets - Built and maintained backend services for payments and financial operations using Django/DRF + FastAPI, focusing on correctness, traceability, and production stability. - Integrated multiple payment / banking providers (callbacks/webhooks, reconciliation, retries, idempotency, and failure handling), ensuring consistent state across distributed systems. - Implemented async processing with Celery + Kafka for high-volume event flows (transaction updates, notifications, settlement/reconciliation jobs) - Delivered real-time features with WebSockets (status updates, transaction state changes), designed for reliability under load. - Contributed to AWS infrastructure and deployments (ECS/ECR, EC2, S3, LB), improving operational readiness with monitoring, logs, and incident response practices. - Worked across Web3 integrations (including Tron API) and off-chain services, bridging blockchain events with internal accounting/business logic.

• Built and maintained backend services for payments and financial operations using Django/DRF + FastAPI
• Integrated multiple payment / banking providers with callbacks/webhooks, reconciliation, retries, idempotency, and failure handling
• Implemented async processing with Celery + Kafka for high-volume event flows
• Delivered real-time features with WebSockets designed for reliability under load
• Contributed to AWS infrastructure and deployments improving operational readiness
• Worked across Web3 integrations including Tron API and off-chain services

Senior Full Stack Developer

Tech: Python, Django, DRF, TypeScript, VueJS, REST API, GraphQL, PostgreSQL, Sentry, SnowFlake, Stripe, AWS, PyTest, Redis, Linters It’s startup in telemedicine and telehealth area, has deep integrations of Stripe, Segment, Snowflake, AWS (service is serverless) - saved 100000$/month for company migrating from Segment to own realisation - adapted main features of third-party service and implemented messaging as part of a system that improves interaction medical staff with clients - developed part of the system that improved moving a client along the treatment plan and tracking the status of patient’s progress - Build a RESTful API that enabled the integration of third-party services with web applications like Stripe, Aircall (for processing data about voice calls), Twilio (send email/SMS), GetLabs laboratory), Intercom (for support clients) - Implemented automated testing(pytest) using golden files which increased code coverage of important system parts - Implemented phone calls processing across Aircall API that increased call processing time by 3 times

• Saved 100000 USD/month for company migrating from Segment to own realisation
• Adapted main features of third-party service and implemented messaging as part of a system that improves interaction medical staff with clients
• Developed part of the system that improved moving a client along the treatment plan and tracking the status of patient’s progress
• Built a RESTful API that enabled the integration of third-party services with web applications
• Implemented automated testing using pytest with golden files which increased code coverage of important system parts
• Implemented phone calls processing across Aircall API that increased call processing time by 3 times

Team Lead of Software engineers

https://dimoapp.com/ -Improve the project’s architecture which increased readability, maintenance -Architect and implemented core functionality that allows increased profit by 30% -Reduce critical bugs by 50-60% -Redesign database layer. Queries became faster 2-3 times faster -Introduce ElasticSearch in the project -Wrote tests to 90% coverage (tests Unit tests, Selenium tests) -Created and implemented documentation on critical parts of the system

• Improved the project’s architecture which increased readability and maintenance
• Architected and implemented core functionality that increased profit by 30%
• Reduced critical bugs by 50-60%
• Redesigned database layer, making queries 2-3 times faster
• Introduced ElasticSearch in the project
• Wrote tests to 90% coverage
• Created and implemented documentation on critical parts of the system

Software Developer

Areas: Medicine, Fitness, Video stream, online shop, Monitoring of seismic activity of Panama Technology: Python, Django, Flask, MySQL, PostgreSQL, Celery, AWS, ElasticSearch, Ansible, Git, JS, Angular, React, D3.js, Leaflet.js