William is available for hire
Hire WilliamWilliam Riancho
Verified Expert in Engineering
Blockchain and Full-stack Developer
Paris, France
Toptal member since November 3, 2022
Bio
William is a full-stack software engineer specializing in blockchain application development. He works with products from the design phase to development and deployment into production. He has led teams of engineers and graphic designers, developed mobile apps for iOS and Android, established cloud architectures, worked with regulators to create MiFID-compliant systems, built eCommerce funnels for five countries, and conducted A/B testing.
Portfolio
21.co
TypeScript, React, Ethereum, Blockchain, Solidity, Full-stack, Smart Contracts...
CloseCross
Kotlin, TypeScript, React, C, Full-stack, REST APIs, Amazon Web Services (AWS)...
Jeffrey
React Native, TypeScript, Full-stack, GraphQL, REST APIs, Microservices...
Experience
- C++ - 12 years
- Linux - 12 years
- Kubernetes - 4 years
- TypeScript - 4 years
- Blockchain - 4 years
- React - 4 years
- Ethereum - 3 years
- Rust - 1 year
Availability
Part-time
Preferred Environment
Kubernetes, Linux, TypeScript, Rust, Ethereum
The most amazing...
...product I've developed is the world's first MIFID-regulated blockchain-based non-custodial derivatives platform.
Work Experience
Senior Full-stack Engineer
2021 - 2022
21.co
- Created the data engineering department to centralize and streamline all data needs across the company.
- Led a team of developers working on innovative blockchain products.
- Conducted research and development on blockchain products.
Technologies: TypeScript, React, Ethereum, Blockchain, Solidity, Full-stack, Smart Contracts, Ethereum Smart Contracts, Web3.js, REST APIs, GraphQL, Amazon Web Services (AWS), Microservices, Software Architecture, Technical Leadership
Senior Full-stack Engineer
2019 - 2021
CloseCross
- Developed the world's first MIFID-regulated blockchain-based non-custodial derivatives platform.
- Established the cloud architecture of an application across multiple data centers.
- Reported to a CTO as the technical leader of the development team.
Technologies: Kotlin, TypeScript, React, C, Full-stack, REST APIs, Amazon Web Services (AWS), Kubernetes, Smart Contracts, Web3.js, Solidity, Microservices, Software Architecture, Technical Leadership
Chief Technical Officer
2018 - 2019
Jeffrey
- Designed and developed a mobile app for iOS and Android.
- Led a team of engineers and graphic designers to design a mobile application.
- Established the cloud and front-end architectures of the application.
Technologies: React Native, TypeScript, Full-stack, GraphQL, REST APIs, Microservices, Google Cloud, PostgreSQL, Software Architecture, Technical Leadership
Senior Full-stack Engineer
2016 - 2018
Bloomon
- Developed an eCommerce funnel using React and Laravel for five countries and conducted A/B testing.
- Managed a team of developers using the Agile methodology.
- Contributed to the company's ERP built on top of Laravel.
Technologies: React, Laravel, Amazon Web Services (AWS), Technical Leadership, Software Architecture
Senior Full-stack Engineer
2015 - 2016
Nanocloud
- Developed an entire product to access a virtualized Microsoft Windows environment in a browser (Xen, Go, C, C++, Node.js, Ember.js, WinAPI, and WebRTC).
- Led research and development on low latency remote desktop access technology using WebRTC.
- Contributed to the design and development of the product.
- Handled the deployment of the solution on customer's infrastructure across multiple data centers.
Technologies: C++, Go, Windows, WebRTC, Software Architecture, Technical Leadership
Full-stack Engineer
2015 - 2015
Linkurious
- Contributed to the web application enabling customers to interact with various types of graph-oriented databases such as Neo4j.
- Designed and developed the application audit system from scratch.
- Led the research and development of the multi-database support of the application.
Technologies: Neo4j, Node.js
Full-stack Engineer
2011 - 2015
OP1C
- Led the development of 100+ applications for brand social marketing on top of Facebook, Instagram, and Twitter.
- Spearheaded the research and development of interactive applications for brand marketing.
- Led the design and migration of the cloud infrastructure.
- Managed and mentored software engineering interns.
Technologies: PHP, JavaScript, Ember.js, Software Architecture
Teaching Assistant
2010 - 2012
EPITECH
- Involved in the school organization including student supervision.
- Led the development of internal tools and project evaluations.
- Contributed to the school's network infrastructure deployment and management.
Technologies: C, C++
Experience
Jeffrey Mobile App
A React Native-based mobile app developed for iOS and Android that integrates a chat system facilitating communication between customers and service providers. The application integrated a payment system and a back office for the operations team.
CloseCross
The product implemented a patented technology that defines a derivative trading platform on top of the Ethereum blockchain. We developed a receipt exchange protocol based on state channels to tackle this challenge.
These receipts are signed by both the server and user with their cryptographic keys so that it can be verified that both parties have intentionally taken part in the transaction.
We also worked closely with the Malta Financial Services Authority (MFSA) to ensure the application complied with the Markets in Financial Instruments Directive (MiFID) of the European Union.
These receipts are signed by both the server and user with their cryptographic keys so that it can be verified that both parties have intentionally taken part in the transaction.
We also worked closely with the Malta Financial Services Authority (MFSA) to ensure the application complied with the Markets in Financial Instruments Directive (MiFID) of the European Union.
Education
2010 - 2016
Master's Degree in Computer Science
The Paris Graduate School of Digital Innovation (EPITECH) - Paris, France
Certifications
NOVEMBER 2022 - PRESENT
LFS158x: Introduction to Kubernetes
edX
AUGUST 2021 - PRESENT
PH125.3x: Data Science: Probability
edX
JUNE 2021 - PRESENT
PH125.2x: Data Science: Visualization
edX
Skills
Libraries/APIs
React, WebRTC, Node.js, REST APIs, Web3.js
Languages
TypeScript, Rust, C, C++, Kotlin, Go, PHP, JavaScript, Python, Solidity, GraphQL
Platforms
Blockchain, Ethereum, Kubernetes, Linux, Amazon Web Services (AWS), Windows
Frameworks
React Native, Laravel, Ember.js
Paradigms
Microservices, DevOps
Storage
Neo4j, Google Cloud, PostgreSQL
Other
Data Science, Probability Theory, Full-stack, Smart Contracts, Ethereum Smart Contracts, Software Architecture, Technical Leadership
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hours—not weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.
Top talent is in high demand.
Start hiring