About John Keizer | Contra John Keizer

John Keizer

John Keizer

⭐️⭐️⭐️⭐️⭐️ Top 10% Mobile | Web | AI Engineer: High Quality

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Sunnyvale, USA

Work Posts About

Sunnyvale, USA

Meet John

I’m an experienced software developer with over 14 years of hands-on experience in C#, JavaScript, Python, C++, Go, PHP, and Java, delivering scalable and high-performance applications across diverse industries. Since 2018, I’ve specialized as an AI/ML Engineer with deep expertise in Large Language Models (LLMs) and Generative AI, building production-ready systems that automate workflows and drive

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Rate

$75 - $100/hr

Skills and tools

Mobile Engineer Web Developer Fullstack Engineer Backend Engineer UI Designer Flutter Developer Frontend Engineer Data Engineer Web Designer Dot Net Backend Developer

Visual Studio Code

Details

Sunnyvale, USA

(GMT-8) Pacific Standard Time (PST), ±3 hours

Professional Working Proficiency in English

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For companies

For companies Manage team projects Share hiring workspace Post jobs Discover contractors Sign contracts Approve invoices Global payments & tax compliance

Use Cases

For companies For freelancers For partners For agencies For VCs

Resources

Challenges Partnerships Advertising Creative Human Data Human Creativity Benchmark Creative Arena Project-based hiring calculator Guide to flexible hiring Guide for agencies Creator tools awards Customer stories Blog FAQs for freelancers FAQs for companies Referrals

Hire Freelancers

Explore all Top independents Design Engineering Marketing Music & audio Social media Video & animation Product Business consulting & HR Other

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