Rade Santrac Senior Full-Stack Developer · AI Engineer · Shopify Expert
I help founders and businesses ship MVPs that actually launch, from idea to production in weeks, not months. My focus is AI-powered products, custom SaaS, mobile apps, and complex e-commerce builds where speed and architectural judgment both matter.
Profile
Over 15+ years I've built and shipped end-to-end products across the full stack, and lately, a lot of AI-powered systems: LLM integrations (OpenAI, Anthropic, open models), RAG pipelines, AI agents, structured outputs, and prompt engineering with evals. Currently expanding into fine-tuning.
I build automation & agent workflows (custom AI automations, browser-use agents, and end-to-end pipelines that replace manual ops work) and mobile & SaaS MVPs with React Native (Expo), Next.js dashboards, FastAPI/Node backends, payments, and the unglamorous infrastructure that makes products reliable.
I have an electronics background, so I take on MVPs that span software and hardware like IoT, Bluetooth, display systems, embedded integrations. And on Shopify I've spent nearly a decade: theme development, Liquid, custom apps, performance optimization, complex storefront logic. If it can be done on Shopify, I've probably done it.
I give honest scope assessments before quoting, write clean handoff documentation, and stay reachable during the build. Strong bias toward shipping.
Strengths
Rade Santrac
Availability & location
Skills
The stack I reach for most. I adopt whatever the project actually needs - language is rarely the bottleneck.
AI / ML
Frontend
Backend
Data / Vector
Cloud / Infra
E-commerce
On languages & frameworks: after 15+ years, language is less of an obstacle than most assume. Picking up a new or rarely-used framework is, realistically, a matter of a day at most before I'm productive in it. I optimize for the right tool for the job, not for staying inside a comfort zone.
Projects
A few recent builds. Most client repositories are private under confidentiality, so the public surface is intentionally minimal.
Xposto - AI-powered X publishing platform
Not just a "post generator" - a content ingestion + semantic transformation + autonomous publishing system. Built on a Node.js/Express monolith with a SQLite data layer and a server-rendered, tier-aware dashboard.
- Document pipeline: PDF/DOC/DOCX → text extraction → semantic micro-units → generated posts/threads, with usage tracking that prevents repetitive output.
- Automated RSS/URL pipeline: feed autodiscovery, tier-based polling cadence, dedupe with stable keys, contextual summarization, single or thread modes with quality thresholds.
- Native media + link publishing via the X media API, including auto-extraction of featured images (og:image / twitter:image / JSON-LD) and temp-storage cleanup.
- Scheduling engine with day/time windows, timezone constraints, retries, status transitions, and persistent posting logs.
More on architecture & product logic
- Cron-driven background workers: post publishing (every second), feed ingestion (interval by tier), hourly maintenance cleanup.
- Realtime dashboard updates over an SSE stream for live post/status changes.
- Tier-gated end-to-end (UI + backend): source count, polling interval, post/thread limits, style access, with a unified daily quota across document and feed generation.
- Reliability: defensive dedupe, retry logic with terminal failure states, validated live scheduling/posting/attachment lifecycle.
Page Speed Group - performance platform & ROI engine
Founder and full-stack developer - built the entire product, from the marketing site to the performance-modeling engine behind it, and I deliver the technical optimization work for clients.
- Website Performance ROI Calculator: enter a URL, get a dollar figure for the revenue a store is losing to slow load times.
- Orchestrates lab results + Core Web Vitals, estimated traffic, and AOV in real time through a custom revenue-impact model built around LCP improvement with diminishing returns baked in.
- Validated the model against Google's "Think with Google" performance-to-revenue calculator to keep it anchored to Google's own modeling.
- Client engineering: reworking the critical rendering path, inlining critical CSS, safely deferring render-blocking JS across theme + app stack, validated against field/CrUX data.
Ryder Diamonds - Shopify store, ground-up build
Full-stack developer for a complete Shopify eCommerce store built from the ground up: custom theme architecture, frontend development, backend integrations, and performance optimization, a scalable, conversion-focused shopping experience.
- Custom theme development, responsive UI/UX, product/collection architecture, and reusable components.
- Third-party API integrations, payment gateway setup, cart/checkout optimization, and automation of store operations.
- Worked with Shopify APIs, webhooks, metafields, and custom sections; optimized site speed, SEO structure, and mobile performance for conversion.
Experience
Help founders launch MVPs fast, AI-powered products, custom SaaS, mobile apps, automation systems, and complex e-commerce. LLM integrations, RAG, AI agents, React Native, Next.js dashboards, FastAPI/Node backends, payments, and scalable cloud infrastructure, plus software+hardware MVPs (IoT, Bluetooth, embedded, displays). Nearly a decade of expert-level Shopify. Strong focus on shipping reliable products.
Founded and led an early-stage digital agency focused on advanced web application development. As Project Manager and Lead Developer, directed architecture and delivery of complex web solutions for international clients, scalable multi-tenant systems, custom CMS platforms, payment gateway integrations, and high-performance web apps. An early adopter of emerging technologies, ahead of mainstream adoption.
Education
Electrotechnical High School "Nikola Tesla"
Track record
Contact
Tell me what you're trying to ship. Happy to give a quick read on the right approach before you commit.