About
Full-stack engineer and CTO. I ship web products end to end: product judgment, UI, APIs, data, and the production details that make software hold up for real users.
AI is part of that toolkit when it earns its place — agents, GraphRAG, coaching systems, Shopify sales over SMS/WhatsApp — not the only lens I use.
Through-line: clear scope, fast iteration, and software that ships. Based in Estonia and open to relocation.
Experience
Chief Technology Officer, Elite Skills
2025 - Present | Remote
Built eliteskills.co from scratch as CTO. AI-first platform where agents coach finance students for elite boutique internships and IB roles: technical prep, MD boardroom simulations, and recruiting tools.
- Shipped AI agent systems: coaching flows, interview boardroom agents, generative feedback loops
- Architected the full stack from zero: auth, content, AI integrations, realtime sessions
- Own technical direction end to end on a live product for top-tier recruiting
Co-Founder & Full-Stack Engineer, Sales-Reach
2025 - Present | Remote
AI sales-agent SaaS for Shopify merchants (MENA & EU). Branded personas text customers over SMS/WhatsApp after purchase or abandoned cart, run multi-turn sales conversations, and issue personalized discounts as a commission-based growth channel.
- Owned the operated SaaS layer end to end: internal admin/ops console, messaging infrastructure, billing, Shopify compliance, live demo, and in-browser agent QA (~105 commits)
- Built multi-tenant SMS/WhatsApp on a shared Twilio number pool, usage-based Shopify Billing API commissions, and Protected Customer Data / Toll-Free Verification compliance
- Co-founder owned the AI/persona core; I turned that core into a shippable multi-tenant business
Fullstack Software Developer, Wisehosting
Jan 2026 - Mar 2026 | Hybrid
Full-stack work on production hosting systems and customer-facing features in a fast product environment.
- Surfaced issues early and drove fixes that improved client experience
- Shipped production features with tight ownership in a small team
- Worked across the stack on systems used by paying customers
Software Engineer, RevoTech OÜ
2025 - 2026 | Estonia / Remote
Full-stack and product engineering across web and game systems (React, Node.js, Unity, Unreal), with an eye toward AI-capable product architecture.
- Built production web apps with React and Node.js
- Developed game systems in Unity and Unreal Engine
- Designed MongoDB schemas for multi-user apps
Lead Game Developer, Independent / Contract
2021 - 2023 | Remote
Led small teams on game prototypes and systems. Owned technical direction, task breakdown, and delivery timelines.
- Directed development on Unity and Unreal projects
- Managed team workflows and code review
- Balanced scope, quality, and shipping deadlines
Projects
Sales-Reach
AI sales-agent platform for Shopify merchants (MENA & EU). Branded personas (30+ across Arabic dialects, French, Italian, German, English) text customers over SMS/WhatsApp after purchase or abandoned cart. Multi-turn sales chats, objection handling, personalized discount codes. Commission-based growth channel, not a subscription tool.
Turned the AI/persona core into operated SaaS: admin, messaging, billing, Shopify compliance, live demo, in-browser agent QA.
Stack: TypeScript, Node.js, Fastify, MongoDB, Redis, Twilio, Shopify, OpenRouter, ElevenLabs
EliteSkills
AI-first career platform built around agents: coaching, career planning, learning paths, resume help, and actionable feedback. Generative AI is the product core, not a feature flag.
Agent-driven coaching platform shipped from zero as CTO.
Stack: AI Agents, React, Node.js, TypeScript, Generative AI
https://www.eliteskills.co/
BrainAOS
Self-learning company knowledge graph (Cortex KG) for teams and AI agents. Ingests docs, email, chat, and CRM. Answers with grounded citations. Ships as REST API, MCP server, CLI, and web app with hybrid search, GraphRAG, and connectors for Slack, Gmail, Jira, GitHub, and more.
Organizational memory for humans and agents. Cited answers, multi-tenant.
Stack: AI Agents, GraphRAG, MCP, Node.js, PostgreSQL, Redis
EliteSkills Interview
AI Senior MD boardroom agent that stress-tests interview answers in real time. Follow-up pressure modeled on elite boutique superdays, not a static chatbot script.
Live agent-led interview rehearsal with MD-style questioning.
Stack: AI Agents, Gemini AI, React, Node.js, WebSockets
https://www.eliteskills.co/
SalesBuddy
AI sales coaching where agent clients roleplay conversations, push objections, and give realtime feedback. Feels like a live call, not a quiz.
Sales rehearsal with AI clients and live coaching feedback.
Stack: AI Agents, Generative AI, React, Node.js, Realtime
Kettl
Marketplace for collecting and trading used cooking oil between restaurants and recyclers. Scheduling, transactions, and verified buyers.
Operational marketplace for sustainable waste collection.
Stack: React, Node.js, PostgreSQL, Marketplace
FAQ
Who is Reio Vendelin?
Reio Vendelin is a full-stack software developer and CTO based in Estonia. Reio builds web products end to end (React, Node.js, TypeScript, PostgreSQL, MongoDB) and production AI systems such as AI agents, GraphRAG, and Shopify sales-agent SaaS.
Looking for a software developer in Estonia?
Reio Vendelin is an Estonia-based full-stack software developer (tarkvaraarendaja) available for product, full-stack, and AI engineering work, remote or on-site, and open to relocation. Contact: Reio.vend@gmail.com.
What has Reio Vendelin built?
Sales-Reach, EliteSkills, BrainAOS, EliteSkills Interview, SalesBuddy, Kettl. Reio is CTO of Elite Skills and co-founder of Sales-Reach.
Which languages does Reio Vendelin work in?
English and Estonian.