I help businesses streamline their accounts payable and accounting processes with accuracy, efficiency, and attention to detail. With 6+ years of experience, I specialize in invoice processing, vendor management, account reconciliations, expense management, month-end close support, and financial reporting. I also implement and optimize accounting tools like Ramp to improve workflows, strengthen controls, and save valuable time.
I am an Experienced and results-driven Certified Billing and Coding Specialist(CBCS) and Credentialing Expert. I have a demonstrated ability to proficiently assign ICD-10, CPT, and HCPCS codes. I also understand the process of handling denials and working with insurance companies to resolve them. I have 15 years of experience in every facet of Medical Billing and Coding, including A/R and Revenue Cycle Management. I have handled the Credentialing for numerous practices and know the portals well and how to keep the process up to date and organized for each Provider. I have also furthered my education in the past few years, including HIPAA Certification in Mental Healthcare. I am and have always been dedicated to optimizing the reimbursement processes for healthcare providers with precision and efficiency.
Sergei T.
Full-Stack Developer | Web & Mobile Applications | React Native
San Francisco, California
$10/hr$10 per hour5.0 (7) 11 jobs $1K+ total earnings
Full-stack developer based in San Francisco (PST). I take founders from idea to a live, production app, fast, and with senior-level execution.
In the past year I've shipped 5 products end-to-end:
• ChekBack - a receipt-cashback app
• PhotoOffice - an AI passport-photo service
• ChessTourism - a chess-tournament platform
• Pluto - a field-service management system for home-service companies
• MotoSocial - a social network for motorcyclists
Each one went from concept to deployment, including auth, payments, integrations, and infrastructure.
Why clients work with me:
• US-based, real-time overlap with your business hours
• Native, clear English on calls and in writing
• Senior delivery - I ship working software, not just plans
• I stay with you until your app is published - I never leave you alone with your issues or concerns
• Warranty after delivery - if something breaks on my work, I fix it, no extra charge
Core stack: React, React Native, Next.js, TypeScript, Node.js, PostgreSQL.
Also: Python (FastAPI/Django), Expo, Redis, AWS/Hetzner/Cloudflare, CI/CD, REST & GraphQL, CRM and third-party integrations.
Best fit for: founders and startups who need an MVP or full product built right, the first time.
Send me your idea and I'll reply with a rough scope and timeline. No charge.
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