Dean Rexines

• Solidity, Hardhat, React JS, Node JS, Tailwind CSS • Founded and built the Mash platform, a primary NFT marketplace (currently deployed on ETH/Polygon) & DAO for creators to facilitate cross-media artist collaboration, innovate the minting process by allowing users to create custom multimedia NFTs curated from original works, and fully-decentralize artist/fan community discovery • Architected and implemented entire full-stack NFT launch marketplace from scratch w/ full-service suite of gas-optimized Solidity contracts ERC721-C contracts to manage collaborative, cross-media NFT collections Perpetual, code-enforced royalties built directly into contract + interface support for popular secondary NFT marketplaces Payments contracts to escrow, manage, and facilitate payouts to artists from mint proceeds, split dynamically between collaborators Full-stack web application with sleek UI for artists to share their multimedia collaborative collections & allow end users to select their favorite works and remix them into a “Mashed” masterpiece Secure web3 client + web2 IPFS gateway to enable minting NFT’s & saving metadata on a decentralized network on the fly • Manage small team of engineers/designers and play instrumental role in running our DAO, including artist relations, funding, recruiting, and design

• Typescript • Implement essential features in core backend services including blockchain transactions API, complex token vesting algorithms, and seamlessly integrating web2 platform with web3 backend (smart contracts) • Build out core token vesting platform, including work on token distribution, airdrops, allocation vesting scheduling, and token deployment • Work on user-facing platform frontend, including various features and improvements on token vesting dashboards, vesting distribution customizations, and complex scheduling modules

• Solidity, Circom, Typescript • Implement first iterations of core platform, including smart contracts, ZK circuits, and architecture design, from idea stage as first engineering hire • Build out core smart contract protocol using Solidity to facilitate permissionless access to a modular, decentralized network of ZK Proof verification tools and application primitives for developers • Design, research, and implement suite of ZK circuits using Circom, SnarkJS, and ZKEmail to enable trustless, secure computation on email as a data source • Develop end-to-end MVP for Strobe’s first PoC use case, an on-chain prediction market using ZK-verified email alerts as an oracle for settlement source-of-truth

• Java, various AWS services, MySQL • Core developer on Amazon’s Multi Marketplace Advertising (MMA) global stack - scaling cross-marketplace advertising, launching new features for Amazon Sellers/Advertisers in worldwide marketplaces, and optimizing ad-serving algorithms Instrumental work designing and implementing various new advertising features across Amazon’s complex ad-serving stack, working with a team that supports worldwide feature support and data availability Lead engineering roles on launch initiatives of core advertising services in new marketplaces such as Brazil, Singapore, Turkey, and more • Extensive work designing and implementing from scratch various new advertising features and infrastructure scaling frameworks for Sponsored Products & Sponsored Brands (the curated banner and feed ads users worldwide are served dynamically while searching and scrolling on Amazon.com) Made mission-critical code contributions across various different Amazon internal codebases including ad-serving engines, ad-ranking algorithms, and ad aggregators Extensive experience implementing code to perform at global scale, analyzing and improving algorithmic efficiency, and optimizing and troubleshooting database operations/queries at this massive scale • Completely redesigned and re-implemented MMA’s core data models and wrote new internal API libraries for easier cross-team development, faster query speeds, and better runtime efficiency

• Python 3.7, Django, Docker, MySQL, Flask, AWS, SQLAlchemy, Celery, RabbitMQ • Extensive work on the core platform using Python 3.7, Django, MySQL, and Docker: rescheduling algorithm to generate suggestions via Celery tasks for optimal open appointment slots for patients based on complex criteria Work on suggestion generation and filtering logic of core rescheduling algorithm Build out conversational decision tree logic to automate interactions with patients to offer them appointment reschedule suggestions, reschedule patients based on their responses, and update external EHR systems accordingly Design and build internationalization framework to allow core conversational interface to support any language Incorporate support for Twilio SMS and voice calling, optimize 3rd party data processing and API push/pull interactions • Work on integration layer that interfaces with 3rd party EHR systems to efficiently pull and transform various hospital and patient data Create custom method for pulling millions of historical appointment records via Athena/Redox API’s to account for rate limiting, optimize batching for data wrangling and database writing, and merge records from different sources Build out pipelines to pre-process external data and map to internal processes • Create metrics infrastructure from the ground up Design and build metrics framework to scalably and efficiently generate a customizable metrics report and send in CSV format via email Write complex SQL queries (Django ORM) to generate over 50 unique, highly complex data points for important metrics for stakeholders • Create A/B testing framework from the ground up Work on A/B testing library (to be open-sourced!) to allow developers to easily create complex A/B testing features, and add these features to cohorts of patients and providers Design and build microservice application using Flask, Docker, and SQLAlchemy, and deploy on AWS, to allow for simple UX to create and manage A/B features

• Python 3.7 and 2.7, RabbitMQ, Redis, Docker, and SQLAlchemy • Build a distributed microservice architecture from scratch, using Python 3.7 - Personally build the data access layer, to consume Rabbit events, fetch service-specific updates from database, transform data into custom format, and publish messages to Redis master/slave for access in microservice ecosystem - Personally build Rabbit protocol layer, to allow a microservice to consume and publish Rabbit messages, and interface with core layer of microservice to map messages to a handler to apply business logic - Work on core business functionality layer, abstracting protocol, messaging, and message routing, making it easy to build and deploy customized microservices and expose API’s publicly - Dockerize microservices and integrate with CI/CD pipeline - Work with small team on full system planning and design • Work on a FX/cryptocurrency trade settlement platform, that ingests trades in real time from a live FIX feed and validates, processes, and settles trades - Various business/infrastructure features, API’s, optimizations, unit/regression/component/BDD tests, etc. - Real-time, platform-wide updates on new trades, new money movements, etc. to provide users with real-time data for high-throughput trading and settlement • Performance test entire distributed digital settlement platform, diagnose scalability problems, and improve system throughput capacity in production by more than 10x, find root causes - Generate randomized trades at different trade frequencies and write real-time data collection and analysis scripts to diagnose system performance - Rebuild part of the system architecture (in Python), optimize database transactions, indexing, and scaling (Python, SQL, and AWS), and formulate and propose new technical strategies for the future • Build the notifications system that the whole platform uses for real-time updates - Core functionality, end-to-end testing pipeline, dockerization

• Build FMECA (Failure Mode, Effects, and Criticality Analysis), an internal application used to identify, analyze, and mitigate risks during system development which will increase launch and vehicle reliability, designed to identify actions which could eliminate or reduce the chance of the potential failures with severe consequences from occurring, and help engineering teams be more productive • Sole software engineer, from idea stage to delivering FMECA application into production for internal engineering teams • Worked with product managers and users (SpaceX Flight Reliability engineers) over course of development, for planning/coordination (JIRA), feedback, and feature discussion • Full-stack development (C# backend, AngularJS/HTML/CSS frontend, MSSQL database, testing, etc.)

• Putting brick-and-mortar businesses in the digital space • Enables secure user authentication and user profiles with search functionality for Customers to find local Businesses, view their menu, place an order, and pay in-app • Easy-to-use interface with sleek custom UX/UI design for Businesses to bring their inventory online in a meaningful way, and features to allow communication with Customers • Stand-alone server written in Ruby to seamlessly connect users to Stripe from iOS app and securely handle transactions • iOS app built with Swift, Firebase, Google Maps API, and Stripe API

• Creating a file management system from scratch, for integration into SiteCompli’s new Retail software, a compliance management product to be sold to real estate clients nationwide • Implementing and testing a file-chunking algorithm to allow uploading files of any size via secure cross-origin requests, that utilizes digital-signing • Using Python on backend and integrating Plupload API into front-end Javascript to build a client-side-to-AWS file upload • Improving and optimizing backend testing infrastructure and writing extensive API tests • Working with AWS S3, Sqlalchemy, Postgres, RethinkDB, and RabbitMQ

• Develop software in C# aggregating user activity within the firm, including output tasks and error reports, into a single application to enable a simple interface for querying relevant information (to be used as native software app by multiple teams within department upon leaving the firm after summer internship) • Create a web application in Java for querying real-time transaction data on company servers, integrating custom class libraries with existing ones, and displayed in XML in web browser over a secure network • Organize a document thoroughly explaining expansive Java applications and class libraries in an orderly way, enabling business analysts in firm to understand inner technical workings of the financial applications they use