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Verified Expert in Engineering
Software Developer
Riga, Latvia
Toptal member since February 4, 2022
Bio
Valts is a senior full-stack engineer with 20+ years of experience building production systems, from national ticketing and rail platforms to high-volume payments and IoT fleets. He specializes in AI and automation, including large language model (LLM) pipelines, structured output, multi-agent systems, Retrieval-augmented Generation (RAG), and data automation. Valts works across the stack, from React and Next.js to Node.js, TypeScript, back-end systems, and device protocols.
Portfolio
The Bold Collective LLC
HTML, JavaScript, PostgreSQL, Stripe, Node.js, Large Language Models (LLMs)...
Rustle Baby
Next.js, TypeScript, tRPC, Drizzle ORM, PostgreSQL, React, Tailwind CSS, Zod...
Mobilly
TypeScript, Node.js, Android, iOS, Cordova, Express.js, Firebase, React Native...
Experience
- JavaScript - 16 years
- Web Scraping - 7 years
- TypeScript - 7 years
- Node.js - 7 years
- React - 6 years
- Next.js - 3 years
- React Native - 3 years
- n8n - 2 years
Preferred Environment
WebStorm, OS X, NeoVim Text Editor
The most amazing...
...thing I've developed is a Latvian national vaccination registration portal with 1.5 million users in the first week. I worked as the lead front-end engineer.
Work Experience
AI Engineer, Content Automation Platform
2026 - PRESENT
The Bold Collective LLC
- Built the core AI engine for a real estate marketing platform that turns a single property listing into 60+ social media posts across 6 platforms, automating 6 weeks of content that agents previously created by hand.
- Automated the end-to-end publishing pipeline, moving posts from AI generation through an approval workflow to scheduled multi-platform posting without manual intervention.
- Rebuilt the agent dashboard in Next.js, delivering listings management, live performance stats, and one-click controls to pause, resume, and approve content.
Technologies: HTML, JavaScript, PostgreSQL, Stripe, Node.js, Large Language Models (LLMs), Automation, Agentic AI, n8n, Next.js, Software Architecture, Multi-tenant Architecture, Multi-tenant SaaS, SaaS, Analytics, Startups, Early-stage Startups, Caching, Third-party APIs, Third-party Integration, LLM Integration, Real-time Analytics, Data Visualization, Cloud Infrastructure, Social Media APIs, Full-stack, Full-stack Development, Architecture, APIs, Vercel, Supabase, OAuth, User Experience (UX), User Interface (UI), Docker, Integration, Workflow Automation, Workflow Automation & System Integration, AI Agents, Claude, Claude API, Claude Code, Software as a Service (SaaS), Python, Amazon Web Services (AWS), Webhooks, API Integration, AI Integration, Artificial Intelligence (AI), Claude Agent SDK, Model Context Protocol (MCP)
Full-stack Developer, Healthcare SaaS & Patient Data
2025 - PRESENT
Rustle Baby
- Built a multi-tenant SaaS platform for lactation consultants covering the full client lifecycle - public intake, scheduling, clinical notes, invoicing, and longitudinal child health tracking.
- Built an intake-to-client pipeline where a single public submission spins up linked client, child, and consultation records through a review queue, with soft-reject and full intake history.
- Engineered a consultation state machine running from scheduling through documentation to finalization, with multi-currency invoicing and self-hosted PDF rendering built into the workflow.
Technologies: Next.js, TypeScript, tRPC, Drizzle ORM, PostgreSQL, React, Tailwind CSS, Zod, Clerk, Software Architecture, Multi-tenant Architecture, Multi-tenant SaaS, SaaS, Startups, Early-stage Startups, Third-party APIs, Data Visualization, Full-stack, Full-stack Development, Architecture, APIs, Vercel, Agentic AI, OAuth, Data Security, eCommerce, UI Design, User Experience (UX), User Interface (UI), Integration, OAuth 2, Workflow Automation, AI Agents, Claude, Claude API, Claude Code, Software as a Service (SaaS), Finance, REST APIs, Authentication, Authorization, HIPAA, Core Web Vitals, Search Engine Optimization (SEO), Debugging, CRM, Auditing, Audits, Data Accuracy & Reporting
Senior Engineer | IoT Systems Engineer
2014 - PRESENT
Mobilly
- Led front-end engineering on Latvia's national vaccination registration portal, built in 3 weeks, with over 1 million active users in its 1st days.
- Built the core engine for a national rail ticketing system, handling complex fare calculations and real-time seat inventory.
- Engineered the back-end data flows for high-volume EV charging transactions over the Open Charge Point Protocol (OCPP).
- Built and optimized data ingestion pipelines for a fleet of IoT devices - LPR cameras, entry/exit barriers, and LED displays.
- Built and maintained one of the most popular city-service payment apps in Latvia, used daily across the country.
Technologies: TypeScript, Node.js, Android, iOS, Cordova, Express.js, Firebase, React Native, Front-end, Open Charge Point Protocol (OCPP), FFmpeg, Puppeteer, Automation, React, Internet of Things (IoT), Next.js, Full-stack Development, Software Architecture, Data Pipelines, Data Engineering, Caching, Third-party APIs, Third-party Integration, Real-time Systems, Real-time Data, Real-time Analytics, Video Processing, Cloud Infrastructure, Full-stack, Architecture, APIs, Agentic AI, Web Development, OAuth, Data Security, eCommerce, UI Design, User Experience (UX), User Interface (UI), Mobile, Docker, Integration, OAuth 2, Workflow Automation & System Integration, Software as a Service (SaaS), Finance, Computer Vision, REST APIs, Performance, Privacy, Security, Mapbox, Git, Amazon Web Services (AWS), Authentication, Authorization, Webhooks, Fastify, Core Web Vitals, Search Engine Optimization (SEO), SEO Tools, A/B Testing, Google Analytics 4 (GA4), NestJS, MongoDB Atlas, API Integration, Debugging, Optimization, CMS, Auditing, Audits, Data Accuracy & Reporting, AI Integration, Artificial Intelligence (AI), Claude Agent SDK, Model Context Protocol (MCP), Make.com
Full-stack AI Engineer, Edtech Platform
2025 - 2026
Codename Design Inc.
- Designed and built an AI-driven learning platform that auto-generates interactive educational content for children.
- Built a system that turns structured scenes, rules, and success criteria into dynamic, prompt-engineered AI instructional scripts.
- Delivered end-to-end pipelines spanning content generation, interaction logic, and post-session analysis for iterative improvement.
Technologies: React, CSS, TypeScript, Next.js, Tailwind CSS, JavaScript, Turbo, PostgreSQL, Prisma, LangChain, Langfuse, Large Language Models (LLMs), Airtable, Software Architecture, SaaS, Analytics, Startups, LLM Integration, Full-stack, Full-stack Development, Architecture, Vercel, Agentic AI, UI Design, User Experience (UX), Docker, Integration, OAuth 2, AI Agents, Claude, Claude API, Claude Code, Software as a Service (SaaS), REST APIs, Performance, Privacy, Security, Git, Authentication, Authorization, Webhooks, Core Web Vitals, Search Engine Optimization (SEO), SEO Tools, A/B Testing, Google Analytics 4 (GA4), NestJS, MongoDB Atlas, API Integration, Debugging, Optimization, CMS, AI Integration, Artificial Intelligence (AI)
LinkedIn Automation Developer
2024 - 2025
Tarka Ventures, Inc.
- Designed and built an AI-assisted LinkedIn inbox automation platform for customer engagement, lead qualification, and outbound response.
- Built message ingestion and processing pipelines that analyze inbound conversations, connection requests, and engagement signals at scale.
- Engineered resilient automation that operated reliably against a frequently changing, heavily protected third-party platform.
Technologies: Linkedln, Robotic Process Automation (RPA), Node.js, PostgreSQL, React, LinkedIn API, LinkedIn Ads, LinkedIn Marketing, LinkedIn Connect, Web Scraping, Puppeteer, Prompt Engineering, Large Language Models (LLMs), Next.js, SaaS, Analytics, Startups, Early-stage Startups, Data Pipelines, Data Engineering, Third-party APIs, Third-party Integration, LLM Integration, Social Media APIs, APIs, Scraping, Agentic AI, OAuth, Integration, OAuth 2, Workflow Automation, Workflow Automation & System Integration, Git, CRM, Make.com
Automation Engineer | Data Scraper
2023 - 2024
Supply Modeling Agency
- Built an automated Twitter/X engagement and content scheduling system supporting high-volume, multi-account operations.
- Engineered scalable data pipelines to extract, normalize, and store large volumes of interaction data for downstream analysis.
- Applied AI to classify and structure raw social data into clean, actionable datasets for intelligence use cases.
Technologies: Node.js, TypeScript, Web Scraping, Puppeteer, React, Analytics, Startups, Early-stage Startups, Data Pipelines, Data Engineering, Real-time Data, Social Media APIs, Scraping, Agentic AI, Workflow Automation, Workflow Automation & System Integration, Python
Automation Engineer, Scraping & Desktop Apps
2023 - 2024
Ryze Management Limited
- Built a cloud-based system that scrapes Reddit at scale and posts automatically across many accounts.
- Developed an Electron desktop application that generates AI-assisted content for posts.
- Managed posting schedules and the desktop tool through the Airtable API and workflow automation.
- Built the underlying Reddit data-scraping foundation and internal task-scheduling tooling for the project.
Technologies: Automation, Node.js, Proxies, Scraping, Electron, Web Scraping, Puppeteer, Airtable, Startups, Early-stage Startups, Data Pipelines, LLM Integration, Cloud Infrastructure, Social Media APIs, Agentic AI, Workflow Automation, Python
Android Developer
2013 - 2014
BuzzTale
- Refactored a live Android application onto a modern stack, architecture, and current best practices.
- Ran the application live at multiple real-time social events with many concurrent users.
- Set up automated build and deployment processes for the app's front-end stack.
Technologies: Android, Java, Real-time Systems, Mobile
Game Developer | Designer
2010 - 2011
Amber Games
- Led front-end development on 8VegaPoker, a large-scale social poker game played across social networks.
- Launched a social farming game across more than five social networks, reaching a broad audience.
- Profiled and resolved performance bottlenecks across multiple in-house games to keep them smooth at scale.
- Contributed to game design documents and pitches for new in-house titles.
Technologies: Front-end, Web Development, Web Design, Performance
Social Game Developer, Full-stack
2009 - 2010
Africa Speles
- Designed and built the 1st social game in Latvia, reaching 200,000 active users in its first quarter.
- Developed a popular friend-quiz game on the Hungarian social network, Iwiw.hu.
- Prototyped multiple 3D Flash social games, exploring new mechanics and formats.
Technologies: JavaScript, CSS, HTML, Front-end, Startups, Full-stack, Full-stack Development, Web Development, Web Design
Full-stack Developer, Ticketing & Payments Systems
2007 - 2009
Bezrindas
- Built the 1st and most popular ticketing system in Latvia, selling public transport and event tickets.
- Designed a ticketing and scanner system for live events of over 10,000 attendees at Arena Riga.
- Built a local payments system and owned its security and financial flows end-to-end.
Technologies: JavaScript, CSS, .NET, HTML, Front-end, Software Architecture, Real-time Systems, Full-stack, Full-stack Development, Architecture, Web Development, Data Security, eCommerce, Web Design, Finance, Performance, Privacy, Security
Full-stack Developer, Vehicle Tracking Integrations
2005 - 2006
Mapon
- Integrated the web front-end with vehicle (auto-park) tracking hardware—an early step into IoT and device integration.
- Built multiple in-house tools and internal systems across the full web stack.
- Established the full-stack web development foundation for a 20+ year engineering career; this was my 1st role.
Technologies: JavaScript, CSS, HTML, Front-end, Third-party Integration, Full-stack, Full-stack Development, APIs, Integration, REST APIs
Experience
National Vaccination Registration Portal
It was a joint effort between multiple organizations, and I was lucky enough to have the chance to work on the project as the lead front-end engineer.
The project was completed in three weeks and had more than one million active users in the first few days.
The project was completed in three weeks and had more than one million active users in the first few days.
AI-driven Children's Learning Platform
I helped design and build an AI-driven learning platform that automatically generates interactive educational content for children. The core of the system lets you define structured scenes, rules, and success criteria, which are then prompt-engineered into dynamic, AI-generated instructional scripts, so new lessons can be produced without hand-authoring every step. I worked across the full stack and contributed to end-to-end pipelines covering content generation, interaction logic, and post-session analysis, which fed back into improving future sessions. The stack was Next.js, React, TypeScript, and Tailwind on the front end, with PostgreSQL and Prisma for data, and LangChain plus Langfuse for large language model (LLM) orchestration and observability. My focus was reliable, structured LLM output and making the generated content consistent and safe enough to put in front of kids.
The 1st Social Game in Latvia
I designed and built the 1st social game in Latvia, which reached 200,000 active users in its first quarter. As a front-end and full-stack developer, I owned the gameplay client and the integration with the social network platform it ran on, building for fast growth and a large concurrent audience from day one. I also developed a popular friend-quiz game on the Hungarian social network Iwiw.hu and prototyped several 3D Flash social games while exploring new mechanics and formats. This was early, high-traffic social gaming, long before it was a mature field. It taught me how to ship engaging, performant front-end experiences that scale to hundreds of thousands of users on the web.
Lactation Consultation Management Platform
https://rustle.babyI built a multi-tenant SaaS platform for lactation consultants that covers the whole client lifecycle - public intake, scheduling, clinical notes, invoicing, and long-term child health tracking - replacing the usual mix of spreadsheets, paper notes, and manual invoices. A single public intake form spins up linked client, child, and consultation records through a review queue, and each consultation moves through a state machine from scheduling to documentation to finalization, with multi-currency invoicing and self-hosted PDF generation built into that flow. Consultants assemble recommendation summaries from a hierarchical library of reusable clinical snippets, and weight and feeding data are tracked over time as growth and percentile charts. I also built a full audit trail with before-and-after snapshots of every client portal action, a JSONB-backed tagging system, and trilingual support in Latvian, English, and German. The whole thing is type-safe from the Postgres schema to the UI via tRPC, with per-consultant data isolation.
Skills
Libraries/APIs
Node.js, React, Puppeteer, LinkedIn API, Playwright, REST APIs, Zod, Social Media APIs, Claude API, Zoho API, FFmpeg, Stripe, QuickBooks API
Tools
n8n, Drizzle ORM, Claude, Claude Code, Git, Turbo, Prisma, MongoDB Atlas, Claude Agent SDK
Languages
JavaScript, TypeScript, CSS, HTML, Java, Python, Kotlin
Frameworks
React Native, Next.js, Express.js, Tailwind CSS, Electron, OAuth 2, NestJS, .NET, tRPC, Fastify
Paradigms
Automation, Real-time Systems, UI Design, Search Engine Optimization (SEO), Model Context Protocol (MCP)
Platforms
Linkedln, Vercel, Clerk, Android, Firebase, Zoho CRM, Langfuse, Mobile, Docker, Amazon Web Services (AWS), iOS, Shopify, Mapbox, Telnyx, Twilio, GoHighLevel
Storage
PostgreSQL, Data Pipelines
Industry Expertise
Web Design
Other
Cordova, Front-end, Zoho Books, Proxies, Scraping, Web Scraping, Airtable, Full-stack, Architecture, Supabase, Prompt Engineering, Large Language Models (LLMs), Internet of Things (IoT), Agentic AI, Full-stack Development, Mobile-first Design, APIs, SaaS, Third-party APIs, Web Development, Integration, Workflow Automation, Workflow Automation & System Integration, AI Agents, Software as a Service (SaaS), Performance, Authentication, Webhooks, API Integration, Debugging, AI Integration, Artificial Intelligence (AI), Styled-components, Open Charge Point Protocol (OCPP), Zoho, t3, LinkedIn Ads, LinkedIn Connect, Subscriptions, LangChain, RAG Systems, Software Architecture, Multi-tenant Architecture, Multi-tenant SaaS, Analytics, Startups, Early-stage Startups, Data Engineering, Caching, Third-party Integration, LLM Integration, Real-time Data, Data Visualization, Cloud Infrastructure, OAuth, Data Security, eCommerce, User Experience (UX), User Interface (UI), Finance, Privacy, Security, Authorization, Core Web Vitals, A/B Testing, Optimization, CRM, CMS, Auditing, Audits, Data Accuracy & Reporting, Make.com, Robotic Process Automation (RPA), LinkedIn Marketing, NeoVim Text Editor, Video Processing, Real-time Analytics, Maps, Computer Vision, HIPAA, SEO Tools, Google Analytics 4 (GA4)
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