Available for new projects

Crafting fluid mobile
experiences

Specialized in React Native and Expo. I build performant, cross-platform applications with pixel-perfect design and native-like feel.

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Hello there! 👋

Alex Dev

🔔

50+

Projects

Exp

Recent Activity

🚀

Launched New App

2 days ago

📝

Wrote Blog Post

1 week ago

💻

Merged PR #42

2 weeks ago

Download My Resume

Get a comprehensive overview of my experience, skills, and achievements in PDF format.

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TECHNOLOGIES I USE

React Native

JavaScript

Python

ReScript

TypeScript

MongoDB

MySQL

PostgreSQL

SQL

CodePush

Docker

Fastlane

GitHub Actions

GitLab CI

Google Play

Grafana

Linux

Mobile CI/CD & Delivery

Open Telemetry

TestFlight

Apollo

Django

Electron

GraphQL

NextJS

Node.Js

React

Relay

Effect TS

FP-TS

Mobx

Reanimated

Redux

Clojure

OCaml

Nginx

Featured Projects

A selection of mobile applications built for performance and user experience.

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A comprehensive mobile CRM and marketing dashboard designed for business owners to manage their digital presence on the go. The app integrates real-time advertising performance tracking, lead management, and AI-driven reputation monitoring. Key Features: Real-time Analytics: Interactive performance charts for tracking leads, traffic, and impressions. Lead Management: Instant notifications and automated response tools to boost conversion rates. Reputation Control: Unified feed for monitoring and responding to customer reviews across multiple platforms. Multi-account Support: Seamless switching between different business locations or client profiles.

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A high-load companion app for Princess Cruises passengers, serving as the digital core of the MedallionClass experience. It leverages BLE (Bluetooth Low Energy) to transform the smartphone into a room key, a ship-wide navigator, and a touchless payment tool. Key Features: OceanReady: Streamlined digital check-in and document verification process. OceanCompass: Interactive deck plans with real-time wayfinding and "shipmate" location tracking. OceanNow: On-demand food and beverage delivery to any location on the ship via precise geolocation. JourneyView: Personalized activity timeline and excursion booking system.

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Writing

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Feb 08, 2026

Building osury: Bridging the Gap Between OpenAPI, Type-Safe ReScript, and TypeScript

When you build a frontend in ReScript that consumes a REST API described by an OpenAPI specification, you face a fundamental problem: how do you keep your types in sync with the backend? You can write them by hand, but that is tedious, error-prone, and silently breaks whenever the API changes. You can use an existing codegen tool, but none of them target ReScript — and even fewer generate runtime validation schemas alongside static types.

Jan 16, 2026

Lexer: Breaking Code Into Tokens | Compiler Series Part 2

This is part 2 of my compiler series. If you missed it, <a href="https://coreofkeen.com/blog/why-i-built-a-compiler-for-a-space-game-stationeers-ic10/">part 1 covers why I built a compiler for a video game</a>. Every compiler starts the same way: staring at a wall of text and trying to make sense of it. When you write `let temp = 500`, you see three distinct things — a keyword, a variable name, and a number. But the compiler just sees 14 characters....

Jan 08, 2026

Why I Built a Compiler for a Space Game | Compiler Series Part 1

Most developers treat compilers as black boxes. I was the same — until Stationeers, a space survival game with its own assembly language, pushed me to build one. After hitting the limits of IC10's 16 registers and 128 lines, I created a compiler that translates ReScript into optimized assembly. This is part 1 of a series covering lexers, parsers, register allocation, and the bug that inverted all my conditionals.

Experience

Frontend Architect

at Nyle

2025 — Present

Architecture & Migration. Designed the target architecture Components → Hooks → RTK Query → Effect Services → ReScript Core and executed the migration without halting feature development — through parallel coexistence of legacy and new code. Completed 4 of 6 migration phases, including the pilot (What-If FSM) and 8 domain modules.

Domain Modeling. Developed a domain-variant architecture in ReScript: replaced nullable fields with discriminated union types (Snapshot, WhatIf, PeriodCompare, Timeline, WhatIfTimeline), eliminating an entire class of bugs at the type level — "make illegal states unrepresentable."

FSM (Finite State Machines). Designed and implemented an FSM for What-If functionality (3 states, 4 actions, 18 slider parameters) following the Elm pattern: pure transitions in ReScript + a command interpreter in TypeScript with dependency injection via Effect.

Stack Integration. Wired together ReScript (domain logic, Sury validation), Effect (HTTP, DI, typed errors), RTK Query (cache & orchestration), and React 18 (useSyncExternalStore) into a unified pipeline with strict layer boundaries.

Documentation & Processes. Built a comprehensive architectural documentation system: ARCHITECTURE.md as single source of truth (600+ lines), an ADR process (4 decisions documented), enforcement rules for code review, a TDD workflow, and code generation skills for new services.

Senior React Native Developer

at Mercury Development, LLC

2024 — 2025

Core Development & Accessibility. Led the development of an innovative React Native application, ensuring full compliance with accessibility standards to provide a seamless experience for users with disabilities across pre-cruise planning, in-cruise services, and excursion management.

Architectural Migration. Spearheaded the transition of a mature, large-scale mobile application from legacy data-fetching patterns to a modern GraphQL (Relay) architecture.

Backend Collaboration. Acted as a bridge between mobile and backend teams to negotiate API contracts, design schemas, and ensure seamless feature alignment.

Infrastructure & DevOps. Established a robust development environment by configuring automated code generation and optimizing CI/CD pipelines specifically for React Native.

Technical Leadership. Integrated the Relay client into the core infrastructure and mentored the team on GraphQL best practices and efficient state management.

Lead React Native Developer

at TSS Paratransit

2023 — 2024

Cross-Platform Mobile Application Development using React Native for Ride Booking Platform Tailored for People with Disabilities

Led the development of a cross-platform mobile application using React Native, specifically designed to cater to the unique needs of people with disabilities.

Architected and implemented the business logic using ReScript, leveraging pure functions and nested finite state machines to ensure robust and maintainable code. The logic was compiled into a TypeScript library, allowing the UI team to work seamlessly without requiring specialized knowledge of ReScript.

Developed a monorepo architecture from scratch, ensuring scalability, maintainability, and alignment with business requirements.

Configured and managed a dedicated macOS server for building and deploying the application to both the App Store and Google Play Store, ensuring a smooth and efficient release process.

Automated the build and deployment process using Fastlane, establishing a reliable CI/CD pipeline that streamlined development and reduced time-to-market.

Company Team Lead

at Distillery

2020 — 2022

Evaluate quotas and conduct interviews. I am in charge of team coordination and communication with the client. I take part in distributing tasks and making technical specifications for specialists. Also, I am directly involved in developing application architecture and completing tasks.
I'm working with a client from the USA (B2B CRM California) for 3 years. We successfully delivered and maintained 2 cross-platform mobile applications.
Technical stack:
React Native / GraphQL

Senior React Native Developer

at Distillery

2019 — 2022

Senior React Native Developer

Frontend Developer

at GMCS

2019 — 2019

Creating an interface for an internal project of a company partner. React / Typescript / Mobx. Frontend development from scratch

Frontend React Developer

at Storiqa Marketplace DBA Storiqa Global Trades Inc.

2018 — 2019

Responsibilities:
MVP Mobile application development (marketplace, web3, React Native)
Development of a web application (marketplace, React)

Frontend React Developer

at Kaspersky

2017 — 2017

Develop an interface for a corporate product using Electron (javaScript)

React Native Developer

at Architech NYC

2016 — 2017

Development of a service for standartisation and automation of the documentation of educational processes in US educational institutions. Frontend development for a financial mobile application in React Native. Development of a mobile application for a US logistics company using React Native + Mobx + TypeScript.

CTO

at Forward 70

2013 — 2016

As an individual entrepreneur, I was working with clients, requirements, the development team, and coding. During these 3 years, we created more than 30 sites and five marketplaces. We built our CRM system and one iOS application. Our company also provided SEO services for various clients.