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in the United States

I help businesses build, modernize, and automate web applications using Laravel, PHP, SQL databases, APIs, and modern frontend tools. I have 10+ years of experience developing business-critical applications, SaaS platforms, internal tools, reporting systems, and integrations for real operational workflows. My background includes enterprise software engineering, freelance product development, legacy system modernization, database design, API integrations, and production support. What I can help with: - Laravel, PHP, Livewire, Vue.js, React, Nuxt.js, TailwindCSS, and Bootstrap applications - REST and SOAP API integrations - SQL Server, MySQL, and PostgreSQL database design, queries, reports, and stored procedures - Business process automation and workflow tools - SaaS application development and maintenance - Payment, billing, Shopify, Square, and Cash App integrations - Legacy application modernization - Production troubleshooting, performance improvements, and reliability fixes - Python automation and data transformation - OAuth, SSO/SAML, Laravel Passport, AWS, Git, CI/CD, and Agile workflows Recent project experience includes: - TogetherPay: Shared billing platform with Square and Cash App integrations, real-time billing cycles, Flutter mobile app, and Laravel backend - Djib-Payroll: AI-powered payroll and HR management platform - SmartyReport: Shopify analytics and reporting tool for e-commerce businesses - Intellink: Community platform for healthcare policy professionals - V-Carte: Digital business card and online service platform - BuildWithAbdallah: Technical education platform covering Laravel, Python, AI, APIs, cloud tools, and software architecture I am comfortable working with both technical and non-technical stakeholders. I can take unclear requirements, understand the business process, design the right technical solution, and deliver reliable software that is maintainable after launch. If you need a developer who can build new features, improve existing systems, connect third-party services, clean up database issues, or automate manual work, I can help.

Most HubSpot work stalls at the same place: the drag-and-drop editor runs out of road, and there's no developer around to take it further. That's usually when I get the call. I'm a HubSpot developer and technical consultant with hundreds of clients served. Clients tend to keep me on the bench. A good chunk of my contracts are second and third jobs with the same people. The difference is that I'm a software engineer who works in HubSpot, not a portal configurator. I write HubL, JavaScript, and Python. I build custom objects, real API integrations, and dynamic sites off HubDB. When HubSpot genuinely can't do something, I build the thing next to it that can. One client brought me in to build an application portal for their AI startup from scratch in Django: 169 hours, shipped, five stars, "a spectacular engineer." What I get hired for: - HubSpot CMS builds: custom themes, modules, HubDB-driven pages, landing pages, email templates - Sales and lifecycle process: lead, deal, onboarding, and support pipelines, built properly and automated - Integrations and automation: Zapier, Make, n8n, or custom API work when the no-code tools hit their limit - Portal audits and cleanup: you inherited a mess from the last agency and need someone to find out what's actually running - Custom apps: Python/Django and Next.js builds that extend past HubSpot's edges - SaaS product operations: standing up product teams and repeatable process for founders scaling past ad hoc Recent feedback: "his HubSpot development work was top-tier." "An awesome HubSpot expert who really knows his stuff." "My second time hiring Jonathan." How I work: you tell me what's broken or what you're trying to build, and I tell you what it'll actually take, including when the answer is "that's simpler than you think" or "HubSpot is the wrong tool for this." I'd rather lose the contract than sell you six weeks of work you don't need. Send me a message or book a consultation. Bring specifics.

Build production-ready AI agents, RAGs with LangChain + GPT for SaaS companies. Cut dev time 50% and scale to tens of thousands of users. Recent client feedback: “Zak was awesome! He delivered exactly what I asked faster than I expected! He is extremely knowledgeable” I don’t just write code, I solve business problems. Whether you need an AI agent handling customer inquiries 24/7, a custom workflow that eliminates manual tasks, or a scalable web application, I deliver solutions that save time and generate ROI. What I specialize in: 🤖 AI Agents & Automation by • Custom ChatGPT/Claude integrations • Workflow automation (Zapier / n8n alternatives) • Data processing pipelines • Lead generation bots ⚡ Modern Full-Stack Development Turning AI-generated prototypes into real applications - Yes, Vibe coding got you 80% there in 2 hours, but now you need the other 20% that actually matters: security, authentication, error handling, database design, and deployment that doesn’t crash at 3am • Next.js 14+ with App Router • React/TypeScript applications • Node.js/Python APIs • Real-time applications (WebRTC, WebSockets) ☁️ Cloud & Infrastructure • AWS serverless architecture • Database optimization (PostgreSQL, DynamoDB) • API design and integration • Performance optimization My approach: Fixed-price or hourly projects with clear deliverables. You get working software, not just hours logged. I handle the technical complexity so you can focus on growing your business. Ready to automate your next bottleneck or build something that scales? Let’s talk.

Pell Software is a 100% US-based software development specialist based in Denver, Colorado focused on partnership and reliable, long-term support. About Us: • 100% US-based — Full-time staff, never outsourced • Prebuilt software templates — Save time & money • 70+ Perfect 5-Star Reviews! — Service-oriented approach • Long-term Partnership Focused — Collaborate directly with software engineers ———————————————————— What We Do: • API Integrations • Custom web programming • AI Development, AI-First Software Development • HIPAA compliant software & integrations • Web portals • Work management systems • Business portals & utilities • Middleware systems • eCommerce solutions • PWAs & desktop apps ———————————————————— Our Tech Stacks: • Microsoft: .NET Core, C#, VB, WebForms, MVC, Razor Pages, Blazor, Azure, MSSQL, Visual Studio, TypeScript • LAMP/WAMP: PHP, MySQL, Linux, Apache • Frontend: Vue, Angular, React, Boostrap • Ruby: Rails, Postgres • Other: git, Jira, Confluence, HTML, Javascript, jQuery, Claude Code, AI Software Development ———————————————————— Platforms & APIs: Authorize.NET, SagePay, MINDBODY Online, Brantree, PayPal, Amazon Pay, Fedex, UPS, FreightQuote, QuickBooks Online, QuickBooks Enterprise, Sage 100, Sage 300, Sage Cloud, Sage Intacct, Acumatica, ClubOS, Active Campaign, SharpSpring, Facebook, Google, FirstData, Counterpoint, Moneris Payments, Braintree, PaceJet, TaxJar, Avalara, Amazon, Facebook, Google, QuickBooks Online, MINDBODY Online, Active Campaign, SharpSpring, QuickBooks Commerce, Counterpoint, UPS, FedEx. ———————————————————— Pell Software, LLC *Check out our reviews online!*

Bachelor of Engineering (B.Eng.) | Yuriy Fedkovych Chernivtsi National University, Ukraine I’m a .NET developer specializing in building reliable, production‑ready systems for e‑commerce, logistics, and workflow automation. I focus on backend engineering, API integrations, and deterministic data pipelines that keep operations stable and predictable. I build Windows services, DevExpress‑based desktop applications, API integrations, and SQL‑driven ingestion engines using C#, .NET, and SQL Server. My work includes deep integrations with Amazon SP‑API, Amazon Ads‑API, and other retail platform APIs, enabling automated workflows, real‑time data synchronization, and operational visibility across systems. I design systems that reduce manual work, improve operational reliability, and ensure data flows correctly between platforms. My approach is practical, engineering‑driven, and focused on long‑term maintainability — building solutions that behave consistently in real production environments.

If your app is broken, behind schedule, or stuck with bugs you can't diagnose, I can help. I specialize in taking AI-built and half-finished apps the last mile: fixing, hardening, auditing, and shipping them to production. I've been building production software for 35+ years, including a decade as CTO and then Chief Product Officer at a fintech platform, where transaction correctness, data isolation, and security were non-negotiable. I still sit in that seat today as a fractional CTO for founders, guiding teams from idea through MVP launch. I've led architecture, run engineering teams, and shipped systems that had to hold up under real operational stakes. I build with AI tooling every day, including Claude and the Anthropic API, and I run my own business operations on an automated AI-agent pipeline I built. That's why my delivery timelines run ahead of standard estimates, and why I know exactly where AI-generated codebases skip guardrails and where they hold up. My recent production work centers on React, Next.js, TypeScript, Supabase (Postgres, Auth, RLS), Node.js, and Stripe. Recent engagements include pre-launch SaaS architecture audits, Supabase RLS and API security reviews, rescuing AI-generated MVPs (Lovable, v0, and similar) into production, and LLM feature integrations. Common engagements: - Pre-launch architecture and security audits, with a written findings and remediation report (Supabase RLS is a specialty) - Stabilizing and finishing AI-built or half-built MVPs - API integrations that fail, timeout, or return incorrect data - Auth, webhooks, and data sync issues - React rendering, state, and performance problems - Node.js / Express backend errors and crashes - LLM features: chat, scoring, extraction, and agent workflows I also work with Web3 systems when a project calls for it, including Ethereum and Solana smart contracts, token integrations, and wallet-based workflows. I'm available for short-term fixes, audits, and ongoing support. If you're not sure what you need yet, start with an audit: you'll get a written findings and remediation report you can act on with or without me.