William Wolff
Verified Expert in Engineering
Full-stack Developer
William has over eight years of experience as a senior software engineer, architect, and consultant. He builds full-stack applications from scratch and solutions that integrate with existing services and infrastructure. For the past three years, William has been deeply involved in building cutting-edge blockchain solutions ranging from NFT platforms over transaction batching to dApp development. He has worked with startups and leading players in the industry like Input Output and more.
Portfolio
Experience
Availability
Preferred Environment
Ubuntu, JVM, Vert.x, TypeScript, Cardano, UTXO, React, Docker, Blockchain, ELK (Elastic Stack)
The most amazing...
...I've built is a lossless staking lottery dApp using Cardano's smart contract language Plutus. Players play for each player's principle's yield.
Work Experience
Stake Pool Operator | IT Infrastructure Specialist
Berlin Pool
- Ran and maintained stake pool for PoS blockchain Cardano with multiple, geographically distributed, fail-safe, redundant server setups.
- Used Terraform for provisioning and Ansible for configuring servers and private networks, security, and hardening while adhering to the IaC principles.
- Followed best practices for secure, automated server provisioning, which included air-gapped environments and key and certificate management.
- Gained experience in Docker container management and Docker Compose for custom images.
Senior Solutions Architect
IOHK
- Created a solution design for the NFT platform to support lending and borrowing for real estate, raising investments from crypto markets.
- Supported design for decentralized identity (DID) and verified credential (VC) solution, Atala PRISM.
- Presented Cardano's extended unspent transaction output (eUTXO) model to the AWS team for integration.
- Supported the pioneering of verified NFTs for preventing possible copies of existing non-fungible tokens for major brands.
Lead Engineer and CTO
MDL Mobility Data Lab
- Developed a JVM back-end service for IoT devices, such as screens and displays mounted on top of cars used for car sharing.
- Built the React front end that displayed real-time advertising streamed from the back end.
- Maintained configuration and deployment of IoT devices via Docker, Ansible, and Terraform.
Senior Software Engineer and Software Architect
Deloitte
- Led a team of 12 engineers. Oversaw and planned development cycles, roadmap, and tasks via Jira.
- Developed and architected automated migration and runtime for interpreted language to Java 8 for a major insurance company.
- Created a 3-step migration process for the software stack and conducted E2E testing in a native environment.
CTO | Co-Founder
CityXcape
- Developed an iOS mobile app, web app, and back end for a social network app allowing players to join virtual scavenger hunts to explore cities and collect digital items (stamps) by verifying locations posted by others.
- Built different back-end versions with Ruby on Rails and later used Django.
- Developed architecture, backup system, and integrated Uber's H3 geospatial hexagon-based grid for mobile for a different map experience.
- Managed up to four engineers while also supporting development.
- Created design artifacts for visual content within the app and a web front end. Everything from icons to logos and group emblems for different city tribes.
Experience
JVM Vert.x-based PoW blockchain
https://github.com/will991/vertx-pow-blockchainCardano Blockchain REST API
https://github.com/adagate-io/adagate-apiCityXcape
UTXO NFT Maker
Skills
Languages
Java, HTML, CSS, Swift, JavaScript, TypeScript, Python, Bash Script, Haskell, GraphQL
Frameworks
Vert.x, JUnit, Spring, Django, Ruby on Rails 5, Spring Boot, gRPC
Paradigms
REST, Responsive Layout, Responsive Web Design (RWD)
Platforms
Blockchain, Ubuntu, Cardano, iOS, Blockchain Platforms, Docker, JVM, Firebase, Amazon Web Services (AWS), Amazon EC2, AWS Lambda, Mapbox, Ethereum
Other
Non-fungible Tokens (NFT), Cryptocurrency, Blockchain & Cryptocurrency, Full-stack, UTXO, APIs, Integration, API Integration, Smart Contracts, Responsive UI, Decentralized Finance (DeFi), Bots, Decentralized Exchanges (DEXs), Decentralized Systems, Decentralization, Plutus, Software Development, Software Architecture, Business to Business (B2B), Entrepreneurship, EUTxO, Google Cloud Functions, Cloud Storage, Firebase Hosting, Firebase Cloud Functions, Uber H3, Geospatial Analytics, Mapbox SDK, Trading, IPFS
Libraries/APIs
React, Lombok, REST APIs, JSON-RPC, PostgREST, Firebase Web SDK, Firebase iOS SDK, Node.js, Mapbox iOS SDK
Tools
Apache Maven, Terraform, Ansible, ELK (Elastic Stack), Logstash, Firebase Cloud Messaging (FCM), Xcode, Firebase Analytics, Firebase Authentication, GIS
Storage
PostgreSQL, Elasticsearch, Cloud Firestore, Firebase Realtime Database, Amazon DynamoDB, Amazon S3 (AWS S3)
Education
Master's Degree in International Business
Hult International Business School - San Francisco, CA, USA
Bachelor of Science Degree in Applied Computer Science
Duale Hochschule Baden-Württemberg (DHBW) - Stuttgart, Germany
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