Senior AI & Frontend EngineerKyiv, Ukraine

Leonid Kuznetsov

🤖 Senior engineer focused on AI agents, frontend architecture, and measurable product impact across enterprise SaaS, Web3, and media platforms.

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🍎 Why teams hire me at a glance.

✨ Eight high-signal business metrics: delivery, speed, AI impact, optimization, team leverage, problem solving, and scaling design.

🚀 Delivery Power

years shipping products

13+

From 0→1 launches to enterprise refactors across AI, SaaS, Web3, and media.

⚡ Performance Wins

frontend speed improvement

+35%

Measured gains from profiling, bundle optimization, rendering fixes, and caching strategy.

🧩 Plugin Systems

platform ecosystems

Built plugins for Figma, Adobe, Canva, VSCode, ChatGPT, WordPress, Google Chrome, Microsoft ecosystems, and browser environments.

👥 Team Multiplier

engineers led

Mentored teams, raised code quality, and improved delivery predictability in product-critical orgs.

🤖 AI Productization

faster AI feature rollout

Agentic workflows, prompts, and RAG pipelines accelerate production-ready AI delivery.

📈 Optimization Depth

latency and waste reduction

-40%

Profiling, rendering optimization, caching, and request batching cut runtime and network overhead.

🤝 Problem Resolution

critical blocker turnaround

<24h

Cross-team collaboration with product, design, and backend keeps delivery moving under pressure.

🏗️ Smart Architecture

capacity scaling potential

Modular systems and automation patterns increase product throughput without linear team growth.

🏢 Companies & Products

🔗 Direct links to the companies and product surfaces where I shipped features and led delivery. Each card shows role, timeline, and impact focus.

10+ Product EnvironmentsEnterprise + StartupB2B & Consumer

Writer

2023 - Present

Core AI writing suite

Senior AI & Frontend Engineer

Tools: AI Studio · Writer Agent · Writer App

Chrome ExtensionAI Product DeliveryTypeScriptReact

🤖 Built Writer Agent + AI Studio Platform

🌟 Crafted high-impact AI product experiences at the intersection of autonomous workflows, enterprise security, and performance-focused frontend architecture.

•🤖 Writer Agent: Developed core features to structure and manage autonomous AI workflows.
•🔗 Knowledge Graphs: Engineered OAuth apps to securely connect external data to AI models.
•📊 Analytics: Built the centralized reporting tool with frontend automation and server-side logic.
•🔐 Security & Access: Designed SSO, SCIM, and IdP provisioning from scratch with E2E testing.
•👥 Platform Architecture: Architected frontend systems for Users, Teams, Roles, and Billing infrastructure.
•⚡ Engineering: Drove refactoring and performance optimization across Writer App and Chrome extension integrations.

LottieFiles

2025 - 2026

Cross-platform Plugin Suite

Senior Plugins Engineer (Contract)

Tools: All Plugins · Plugin Figma · Plugin After Effects · Plugin Animate · Plugin Canva · Plugin ChatGPT · Plugin WordPress · Plugin VSCode

Plugin DevelopmentMulti-PlatformLottieFiles APILottie PlayerOAuth

🎬 Built Multi-Platform Plugin Development Systems

⚙️ Delivered production-ready plugin tooling with secure auth, conversion pipelines, and rendering optimization for large animation workloads.

•🧩 Built plugin systems across design, animation, CMS, and IDE ecosystems.
•🛡️ Implemented OAuth/token handling, secure storage, and host-specific permission flows.
•🔄 Delivered import/export workflows and robust file-conversion pipelines for animation formats.
•🚀 Integrated LottieFiles API + Lottie Player with strong memory, bundle, and caching optimization.

Zenseact (Volvo Cars)

2020 - 2023

Autonomous driving software

Senior Frontend Developer

ReactTypeScriptWebGLD3

🚗 Built Autopilot Vision Ops Dashboard

📡 Delivered interfaces for high-frequency autonomous telemetry with close backend and hardware integration.

•📈 Built dashboards for high-frequency autonomous telemetry and scenario debugging.
•🧠 Delivered real-time WebGL + D3 visual surfaces for engineering and validation teams.
•🔧 Aligned frontend workflows with backend and hardware testing pipelines.

Cato Networks

Contract

Network & Security Admin Panels

Frontend Developer (Contract)

Admin PanelsReactJavaScriptHTML/CSSGraphQLContract

Product: Network & Security Admin Panels

🛡️ Built Network Security Admin Console

🏗️ Led frontend delivery for enterprise control panels managing networks, people, companies, certificates, and security operations.

•🧱 Built new admin screens from scratch and shipped iterative upgrades across existing surfaces.
•🔍 Deep-dived legacy code independently to deliver quick fixes and harden infra-related components.
•✨ Proposed UX + backend interaction improvements for clearer, faster, and more reliable workflows.

MEGOGO

2017 - 2020

OTT streaming platform

Engineering Team Lead

Team LeadershipStreaming PlayerSmart TVPerformance

📺 Led Streaming Frontend Across 4 Platforms

🎯 Owned player and app delivery across web, Smart TV, mobile, and console for high-reliability broadcast scenarios.

•👥 Led a 20-engineer frontend organization across web and client platforms.
•🧭 Owned player and app delivery for web, Smart TV, mobile, and console surfaces.
•🚀 Improved release reliability for high-traffic live and VOD broadcasting.

IdeaSoft

2025

Uniswap v4 analytics platform

Senior Web3 Frontend Engineer

Tools: HookRank

ReactTypeScriptSubgraphUniswap v4

🧪 Built Uniswap v4 Hook Analytics

📊 Built React/TypeScript analytics experiences with subgraph-backed filtering and on-chain metadata exploration.

•🔬 Built analytics experiences for Uniswap v4 hook ecosystems.
•🗂️ Implemented subgraph-backed filtering and on-chain metadata exploration flows.
•⚡ Delivered responsive React/TypeScript data interfaces for protocol insights.

Unizen

2024

Cross-chain DEX aggregator

Web3 Frontend Engineer

WalletsDEXReactTypeScript

🌉 Built Cross-Chain Swap Interface

🔄 Implemented wallet connectivity and swap UX across chains for decentralized exchange workflows.

•👛 Implemented multi-chain wallet connectivity and swap interfaces.
•✨ Improved transaction UX for cross-chain asset exchange flows.
•✅ Delivered production-grade experiences for decentralized trading surfaces.

CTRL (formerly XDEFI)

2023 - 2024

Multichain wallet platform

Web3 Frontend Engineer

Browser ExtensionPolygonEthereumOptimismethers.jsweb3.jsNext.jsstyled-componentsReact

🪙 Built Multichain Wallet + NFT Crafting

⛓️ Built extension and NFT product flows across EVM chains with reliable wallet interactions and minting UX.

•🧩 Built a multichain wallet browser extension for secure cross-chain asset management.
•🎨 Built an NFT crafting platform on Polygon, Ethereum, and Optimism.
•🛠️ Shipped production surfaces using ethers.js, web3.js, Next.js, styled-components, and React.

OneArt

2023 - 2024

Multichain wallet extension

Full Stack Web3 Developer

Wallet ExtensionWeb3ReactTypeScript

🧠 Built Wallet Extension and Marketplace UX

💸 Built secure transaction flows and real-time balances for wallet and Web3 marketplace scenarios.

•🔐 Built wallet extension functionality with secure transaction handling.
•📡 Implemented real-time balances and marketplace-oriented interaction flows.
•🚀 Shipped product features across wallet and Web3 commerce use cases.

Vungle

2020 - 2021

In-app ads platform

Software Engineer

Ad PlatformAnalyticsReactTypeScript

📣 Built Scalable In-App Ad Tooling

📱 Developed features and architecture for ad tooling integrated with analytics and ML-informed workflows.

•🎮 Built scalable ad creation tooling for mobile game teams.
•📊 Shipped architecture improvements for analytics-aware campaign workflows.
•🧰 Improved reliability and maintainability across feature delivery paths.

🔌 Plugins & Integrations Experience

🧠 Deep hands-on delivery across plugin ecosystems and cross-product integrations used by product, operations, and engineering teams.

8+ Plugin EcosystemsOAuth + WebhooksAPI Reliability Patterns

🧩 Plugin Development

🚀 Built and shipped production plugins across multiple platforms.

LottieFiles PluginsFigmaAdobe After EffectsAdobe AnimateCanvaChatGPTWordPressVSCodeMicrosoft Add-insBrowser/Chrome Extensions

References: LottieFiles Plugins · Figma · Adobe After Effects · Adobe Animate · Canva · ChatGPT · WordPress · VSCode · Microsoft Add-ins · Browser/Chrome Extensions

[+]🧭 Browser extensions, especially Chrome extensions for product workflows and enterprise users.

[+]🎨 Figma plugins for design-to-product pipelines and creative tooling.

[+]🧱 Adobe plugins for panel workflows, asset automation, and creator productivity.

[+]🏢 Microsoft ecosystem plugins and add-ins (Office/Teams-oriented workflows).

[+]🌐 Google ecosystem integrations and plugin-style tooling across product suites.

[+]✨ And more.

🔗 Service Integrations

⚙️ Integration work between SaaS systems and internal product workflows.

Platforms

SlackJiraGitHubGitLabLinearMicrosoft productsZoom

References: Slack · Jira · GitHub · GitLab · Linear · Microsoft products · Zoom

[+]🔐 OAuth and auth flows with secure token handling and permission scopes.

[+]🪝 Webhooks and event-driven sync between systems with idempotent processing.

[+]⏱️ API rate-limit handling, retry strategy, backoff, and resilient job execution.

[+]🧭 Data mapping and conflict resolution across different schemas and sources of truth.

⚙️ Performance / Refactoring / Optimization

🛠️ Practical engineering approach for making products faster, easier to evolve, and more reliable in production.

ProfilingModular RefactoringObservability

🔬 Profiling & Performance Debugging

[+]Use React Profiler and browser Performance tools to isolate render bottlenecks and expensive update paths.

[+]Trace memory leaks with heap snapshots, detached DOM checks, and lifecycle cleanup validation.

🧩 Refactoring Strategy

[+]Modularize domain logic to reduce coupling and make high-change areas easier to ship safely.

[+]Reduce complexity with typed boundaries, clearer ownership, and incremental migration plans.

⚡ Optimization Techniques

[+]Improve rendering with targeted memoization, lazy loading, and stable state boundaries.

[+]Reduce bundle/runtime cost with code splitting, caching strategy, request batching, and payload trimming.

🛡️ Reliability Improvements

[+]Strengthen error handling and fallback paths for partial failures in critical user flows.

[+]Add observability via structured logs, metrics, and actionable alerts tied to product outcomes.

🚀 My Projects

🧪 Personal products I built to solve practical user problems.

Product ThinkingFast ExecutionUser Value Focus

JsonResu.me

📄 Tool that helps users create an ideal resume in 3 clicks with fast, structured, and practical output.

Live: https://www.jsonresu.me/

[+]⚡ Resume creation flow optimized for speed and clarity.

[+]🎯 Focused on practical output quality for real hiring use-cases.

🤖 AI Implementation Depth

🌟 Build AI features that actually ship in production, while keeping engineering quality, maintainability, and business outcomes in focus.

Agentic WorkflowsRAG + PromptingTypeScript + Python

🧠 AI Capabilities for Product Teams

🤖 Agentic systems, orchestration, retrieval, and product-focused AI integration.

[+]🤖 Design and ship agentic workflows for production tasks with orchestration, guardrails, and failure handling.

[+]🧠 Build prompt and RAG flows that stay grounded and useful in real product contexts.

[+]🛠️ Implement AI features in TypeScript + Python services and integrate them into existing SaaS products.

[+]🧩 Use subagents, rules, hooks, and tool routing for maintainable multi-step automation.

[+]📈 Apply AI to bots, chats, support workflows, and internal process automation with measurable outcomes.

💻 Core Engineering Stack

TypeScriptReactJavaScriptHTMLCSSCI/CDDockerGitHub CLI

🧰 Applied AI stack when needed: prompt engineering, RAG, LangChain, agent orchestration, and Python services.

📉 Support workload reduction potential

20-45%

Assistant and RAG flows can deflect repetitive support and operations requests.

🔎 Knowledge retrieval speed

Up to 70%

Contextual retrieval and synthesis reduce average time-to-answer for users and teams.

⚙️ Process automation potential

30-60%

Agentic orchestration can automate triage, enrichment, and repeatable workflows.

🚀 Feature delivery acceleration

25-40%

AI-assisted engineering and tooling can shorten implementation cycles.

📌 Outcome ranges are scenario-based and depend on baseline process, product maturity, and data quality.