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EXPLORE
4.2
4.2
100%
$35 USD / Hour
・
Japan (12:40 PM)
・
Joined on September 11, 2025
$35 USD / Hour
・
7+ years as a Full-Stack & AI Engineer building scalable web apps, AI-driven systems, and high-volume data pipelines for startups and businesses. Core Expertise AI / ML: LLMs (OpenAI), NLP, recommendation systems, predictive analytics, RAG (Weaviate), TensorFlow, PyTorch Backend: Python (FastAPI, Django), Node.js, Ruby on Rails, Laravel (PHP) Frontend: React, Next.js, TypeScript Data Scraping: Large-scale scraping, anti-bot handling, automation, ETL pipelines Cloud & DevOps: AWS, GCP, Docker, Kubernetes, CI/CD CMS: Wordpress, E-commerce SEO: Google, AI search engine I deliver production-ready solutions, not just codeclean architecture, scalable APIs, and automation that saves time and money. MVPs Production Fast communication Long-term, reliable delivery If you need AI, scraping, or a full-stack system done rightlets build it.
Ryusei is a great developer and has excellent tech skills. He delivered the job on less than half time. Good understanding and smooth communication with a nice professional behavior. Highly recommended A++ Thanks.
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I would highly recommend Ryusei to anyone looking for reliable and skilled support, and I look forward to working with them again in the future.
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They did an excellent job, incredibly fast and good code quality!
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Brandon W.
$30 USD
Assisted me with AI optimization, very informative and knowledgeable.
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Experience
AI & Full Stack Engineer
Jun, 2023 - Apr, 2025
•
1 year, 10 months
Infobox
Jun, 2023 - Apr, 2025
•
1 year, 10 months
• Implemented data preprocessing techniques to improve model accuracy and efficiency. • Prototyped potential solutions using rapid experimentation methodologies, accelerating product development timelines. • Optimized data processing pipelines for efficient handling of large datasets, resulting in reduced training time. • Collaborated with data engineers to ensure seamless integration of ML/AI models into existing data pipelines, automating decision-making processes.
Tokyo, Japan
Jun, 2023 - Apr, 2025
•
1 year, 10 months
Web3 & Full Stack Engineer
May, 2021 - Apr, 2023
•
1 year, 10 months
80&Co
May, 2021 - Apr, 2023
•
1 year, 10 months
• Collaborated with front-end developers to design and implement user interfaces for DApps. • Analyzed large datasets to identify trends and patterns in customer behaviors so improved data prediction by 5%. • Improved data collection methods by designing surveys, polls and other instruments. • Self-motivated, with a strong sense of personal responsibility.
Tokyo, Japan
May, 2021 - Apr, 2023
•
1 year, 10 months
Junior Backend Engineer
Sep, 2019 - May, 2021
•
1 year, 8 months
Re.inc
Sep, 2019 - May, 2021
•
1 year, 8 months
• Developed robust web applications using JavaScript, Ruby on Rails, and React to enhance user experience. • Implemented CI/CD pipelines using tools like Jenkins, accelerating deployment cycles for faster product releases. • Understood full technology stack and underlying applications, services and databases, resulting in optimal program performance. • Streamlined development processes with the implementation of Agile methodologies and best practices.
Tokyo, Japan
Sep, 2019 - May, 2021
•
1 year, 8 months
Education
Osaka Prefecture University
2016 - 2019
•
3 years
Bachelor of Architecture
Japan
2016 - 2019
•
3 years
Verifications
On time
100%
On budget
100%
Accept rate
100%
Repeat hire rate
50%
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