Leroi

Leroi Anders [відкрити контакти](див. вище в блоці «контактна інформація»)
[відкрити контакти](див. вище в блоці «контактна інформація»)
Senior Software Engineer / Tech Lead [відкрити контакти](див. вище в блоці «контактна інформація») · github.com/leroyanders
AWS Serverless · Node.js · React Native · Next.js Kamianske, Ukraine · Remote (EU / US time zones)

PROFILE
Senior engineer with 7+ years of shipping production TypeScript end to end — from AWS serverless backends to
React Native mobile apps and Next.js web. Architected and maintain a 45-service serverless platform for a
creator-monetization product (auth, subscriptions, Stellar wallet, payments, search) together with its mobile and
web clients. Deep background in fintech and payments, event-driven design and monolith-to-microservices
migrations; hands-on tech lead for small teams. Optimises for reliability, delivery speed and maintainable code.
CORE EXPERTISE
Backend Node.js, TypeScript, NestJS, REST APIs, WebSockets, microservices, event-driven & async
workflows
Serverless & Cloud AWS Lambda, API Gateway, EventBridge, SQS, DynamoDB, RDS, OpenSearch, S3, Serverless
Framework, EKS, EC2, Docker, Kubernetes
Frontend & Mobile React Native (iOS & Android), Next.js, React, TypeScript-shared API contracts, i18n
Data & Analytics DynamoDB data modelling, ClickHouse (materialized views), OpenSearch, PostHog pipelines
Payments & Web3 Stellar SDK (account activation, signed XDR transactions), payment gateways, crypto payments,
high-throughput payment processing
AI-Assisted Dev ChatGPT, OpenAI Codex, GitHub Copilot, Claude Code, Cursor — AI-assisted coding, refactoring,
code review, test generation and documentation
Engineering Monorepos (Yarn workspaces, Nx), CI/CD automation, code review & SOLID, sprint planning,
technical leadership
EXPERIENCE

Mar 2025 — Present Senior Full-Stack Engineer · Cassator Corp.
Washington, D.C. SL8 — social & creator-monetization platform. Full-stack ownership across serverless backend,
Remote React Native app and Next.js web.
BACKEND · AWS SERVERLESS
Architected and maintain a TypeScript monorepo of 45 AWS serverless microservices —
auth, content, paid features, subscriptions, wallet, notifications, search — enabling cross-
service code reuse and faster feature delivery.
Built resilient REST APIs and event-driven workflows on Lambda, API Gateway, DynamoDB,
SQS, EventBridge, OpenSearch and RDS for high-concurrency traffic and reliable async
processing.
Designed a Stellar-based wallet and secure payment flows — account activation, signed
XDR transactions, payment-history APIs — enabling on-platform transactions with minimal
friction.
Raised deployment reliability and developer velocity with multi-stack Serverless Framework
configs and local service-invocation workflows in Yarn workspaces.
MOBILE · WEB
Built and shipped features in the React Native app (iOS & Android) — feeds, paid content,
subscriptions and wallet — consuming typed API contracts shared with the backend
monorepo.
Developed the Next.js web client for creator profiles and paid content, with server-side
rendering for performance and SEO.
Delivered internationalization in 18 languages across backend, mobile and web, and built an
analytics pipeline (DynamoDB → S3 → PostHog) that feeds product metrics into roadmap
decisions.

Stack: TypeScript, Node.js, AWS Lambda, API Gateway, DynamoDB, OpenSearch, RDS, SQS,
EventBridge, Serverless Framework, Stellar SDK, React Native, Next.js, React, PostHog

Jul 2024 — Jan 2025 Senior Node.js Engineer · ThriveState Square Real Estate
UAE · Remote Sole backend engineer — full ownership of backend architecture, delivery and production.
Refactored a core microservice and shipped a production WhatsApp messaging channel
(Baileys, WebSockets) for real-time client communication.
Built modular microservices with NestJS and Nx in a pod-based architecture to speed up
development and maximise code reuse.
Led production deployments and stabilisation; shaped the technical roadmap with product in
sprint planning.

Nov 2023 — Jun 2024 Senior Node.js Engineer · Webeffect / BSX
Israel · Remote Designed a high-throughput, fault-tolerant payment processing service for fintech and
blockchain integrations.
Built CI/CD pipelines and deployment automation for AWS EKS, cutting deploy time and
rollout errors.
Delivered AI-driven data-retrieval services and LinkedIn API integrations that automated
manual operations.

Apr 2023 — Oct 2023 Senior Node.js Engineer · SmartyAds
Ukraine Programmatic ad exchange — real-time bidding at high throughput.
Maintained ad-exchange bidding services with a focus on stability and throughput.
Accelerated analytics with ClickHouse materialized views and scheduled statistics-
aggregation jobs.
Implemented OpenRTB request/response validation for third-party bidders, reducing data
mismatches.

Aug 2022 — Apr 2023 Tech Lead / Senior Backend Engineer · Webeffect / BSX
Israel · Remote Led the engineering department through a monolith-to-microservices migration (Docker,
Nginx, AWS EC2).
Owned task allocation, code reviews and SOLID standards, improving code quality and
delivery predictability.
Integrated payment providers (Payfast, CryptoCoin) with secure, production-ready flows.

Feb 2021 — Jul 2022 Backend Engineer & Team Lead · LeadPanda
Dnipro, Ukraine Led a cross-functional team delivering high-conversion landing pages for Facebook &
Google Ads.
Built a CRM, click-tracking system and bot dialer to speed up campaign launches.

Nov 2019 — Mar 2021 Software Engineer · Wisitech InfoSolutions
USA · Remote Developed and maintained web applications and REST APIs on Node.js / Express for US-
based clients, with MySQL and MongoDB.
Built responsive React front-ends, integrated third-party and payment APIs, and worked
directly with clients on releases.

Mar 2016 — May 2021 Software Developer · Envato Market
Freelance · Remote Built and sold website templates, themes and plugins (JavaScript, jQuery, PHP, HTML/CSS);
delivered custom web projects end to end.

E D U C AT I O N L A N G U AG E S
Bachelor's degree 2023 English Professional working
Dniprodzerzhynsk State Technical University Ukrainian Native
Technical diploma, Radio Electronics 2015 Russian Native
Dnipro Applied College of Radio Electronics German Basic