Len K.

I was building websites for two decades before Claude. Now, AI has equipped me with superpowers. I can ship faster (& cheaper) while still ensuring the app remains secure, versatile, and not supported by spaghetti code.

I've scaled web apps to 300k users, navigated SEC enforcement, and built $10M/yr revenue engines. I specialize in product + software to design, build and ship robust platforms that drive real users and revenue.

Why am I on Upwork?
I’ve spent the last 10+ years building cutting edge products in web3 and fintech. Now, I am leveraging Upwork to expand my footprint and partner with founders in new verticals and industries. My goal is to deliver agency-grade results without the agency bloat.

Why work with me?
Many developers will build exactly what you ask for, even if there is a better, faster, or more profitable way to do it. My approach is different. While you know your business, I know the technology. I use my experience to take the lead on development, offering suggestions and improvements that you may not have thought of.

Recent Highlights:

AdminRx - Multi-tenant SaaS that enables 1-Click launch of Telehealth clinics for GLP1/Peptide treatments. Many integrations for payments (Stripe Connect), affiliates (Fanbasis), EHR and E-Prescribing, HIPAA compliance, GoHighLevel and FB Pixel tracking/webhooks, custom doc signing, and DNS deployment. Powering over 25 live clinics.

DrySupplies - AI driven marketing automation for equipment rental business. Agents monitor real-time weather data to identify severe weather and flood zones, which dynamically triggers localized Google and Facebook ad campaigns and content generation.

G2 Venture Partners - Replaced $15,000/year Affinity subscription with custom API & MPC server for relationship scoring and historical interaction context from millions of internal emails and calendar events across the entire organization.

MyWatchLLC - Custom AI enabled business intelligence tools (monitoring, analysis, ideas, sales). Aggregating millions of monthly watch listings and sales data across several sources for price analysis and trends.

View more highlights on my portfolio website:
🔗 lk-dev•com

Tech Stack:
Frontend: Next.js, React, Vue, TypeScript, Tailwind CSS, Playwright
Backend & DB: Node.js, Nest.js, Express, SQL/NoSQL, Prisma, Supabase, AWS/GCP
Creative Tech: Framer, Three.js, React Three Fiber (R3F), P5.js, Canvas, Generative Art Identity & Payments: Clerk, JWT, OAuth, Stripe Connect (High-conversion checkouts) Web3: Bitcoin, Ordinals, Taproot, EVM, ETH, SOL, NFT, DeFi, GameFi, embedded wallets