Sean Shillo, Full-stack Architect and Developer in New York, NY, United States
Sean Shillo

Full-stack Architect and Developer in New York, NY, United States

Member since May 20, 2020
Sean is a senior full-stack developer and architect who has delivered many web and mobile projects, including ones that needed to be robust enough to process heavy data workloads. He's worked with several front-end and back-end frameworks, including Python, Ruby, JavaScript, TypeScript, Rails, Django, Node.js, and PostgreSQL. Sean's performed both as an individual and as a manager, and he's capable of contributing quickly with little guidance as well as advising on best practices.
Sean is now available for hire


  • Ikasi
    Amazon Web Services (AWS), Scikit-learn, Pandas, PostgreSQL, Jenkins...
  • Crabel Capital Management
    JavaScript, TypeScript, React, Node.js, Material-UI, Vue, APIs, Architecture...
  • Adaptly
    React, Amazon Web Services (AWS), PostgreSQL, Scala, Clojure, AWS...



New York, NY, United States



Preferred Environment

GitHub, Trello, Asana, Slack, Visual Studio Code, Vim Text Editor, Ubuntu, MacOS

The most amazing...

...platform I've developed is Adaptly, a social media ad platform that grew to $60 million in revenue and has 100 employees.


  • CTO | Co-founder

    2015 - PRESENT
    • Architected and built a data science platform that allowed the easy deployment of machine learning models and could be integrated with dashboards. Worked with a product manager, designer, and two developers to accomplish this.
    • Developed a platform using Docker, Django, and PostgreSQL on the back end. The front end consisted of Angular and TypeScript.
    • Set up a Kubernetes infrastructure on AWS using Terraform, Jenkins, RDS, Kops, EFS, and Jenkins.
    • Led weekly sprint planning meetings with all the tasks stored in Asana.
    • Managed two developers, conducted regular one-on-ones, and performed code reviews.
    Technologies: Amazon Web Services (AWS), Scikit-learn, Pandas, PostgreSQL, Jenkins, Kubernetes, AWS, Angular, TypeScript, Django, Python, APIs, Architecture, DB, DevOps, Back-end, Google Cloud Platform (GCP), Technical Leadership, REST APIs
  • Full-stack Developer

    2020 - 2022
    Crabel Capital Management
    • Developed a React app that allowed the internal team to queue multiple changes to manage financial accounts for different dates. Wrote stored procedures in SQL server so that the front end could fetch data using the company's custom back-end service.
    • Set up event monitoring for Node.js applications using LogicMonitor. A groovy script was created for the LogicMonitor that would hit internal APIs to get status information and then store that information and create alarms.
    • Maintained multiple React and Vue.js projects, including updating libraries, upgrading interactions with back-end services, and adding new features.
    Technologies: JavaScript, TypeScript, React, Node.js, Material-UI, Vue, APIs, Architecture, DB, DevOps, Back-end
  • Vice President of Engineering

    2011 - 2015
    • Engaged as the first developer at Adaptly, an early-stage startup, when the company consisted of five employees. Promoted to team lead and then VP of engineering as the company grew.
    • Architected and helped build out the Adaptly product while working with the product and key stakeholders. Adaptly grew to over 100 employees and $60 million in revenue during this time.
    • Scaled PostgreSQL to be able to handle a high workload that had initially started crashing the original single server.
    • Developed a platform that quickly responded to changes in the Facebook Ads API through which the platform allowed clients to deploy their ads.
    • Managed a team of 12 developers, conducted one-on-ones, and oversaw the hiring process.
    Technologies: React, Amazon Web Services (AWS), PostgreSQL, Scala, Clojure, AWS, Backbone.js, Ruby on Rails (RoR), Ruby, APIs, Architecture, DB, DevOps, Back-end, Google Cloud Platform (GCP), Technical Leadership, REST APIs
  • Senior Developer

    2010 - 2011
    • Collaborated with a team of eight on a redesign of the website and WordPress upgrade.
    • Developed and customized WordPress plugins needed for the new website.
    • Tracked bugs and features using Jira while working in sprints.
    Technologies: MySQL, JavaScript, PHP, WordPress, APIs, Back-end
  • Developer

    2009 - 2010
    • Developed the iOS applications and back-ends in PHP for a mobile consulting company.
    • Created a system on Android and PHP that allowed delivery drivers to update the statuses of packages.
    • Built NYCMate, an application that provided subway maps of New York City and the ability to find subways needed to reach your destination; this was before Google Maps had this functionality.
    Technologies: CakePHP, MySQL, Android, iOS


  • NFT Trading Bot

    The bot buys NFTs that it finds underpriced and resells them for a higher price. The project consisted of a few pieces.

    Smart Contract
    • A proxy contract has been created to allow for easy upgradeability.
    • Role-based authentication is used so multiple accounts can interact with the contract
    • Sends and receives ERC20 and ERC 721 tokens
    • Interacts with contracts from NFT marketplaces to buy and sell NFS
    • Deployed using Hardhat

    Custom Harmony Node
    • The bot searches for opportunities on the Harmony blockchain.
    • The Harmony blockchain was forked, along with go-libp2p, which is used for networking. Heavy modifications were made so that the bot could listen to transactions in the mempool and submit the buy transactions in the same block.
    • The custom node is deployed to multiple servers worldwide to reduce latency.

    Searcher and Prediction
    • The custom Harmony node uses precomputed price predictions based on different traits of NFTs.
    • A Python application pulls data directly from the blockchain and the graph APIs, floor prices are computed, as well as a predictive model. These prices are then stored in Redis, which the custom node can access.

  • Ikasi

    The platform helps data scientists quickly develop and deploy machine learning models for predicting user behavior. The system also allows data scientists to build dashboards quickly.

    I developed the back end with Django and PostgreSQL, and the front end was built with Angular and TypeScript. Currently, it is running on Kubernetes on AWS.

  • Adaptly

    The front end was built on Backbone.js, and the back end was built on Ruby on Rails, Clojure, Scala, and PostgreSQL, along with featuring multiple services.

    I was the first software developer at the company and later became the VP of engineering as the company grew to millions in revenue and over 100 employees. I architected the entire platform, developed it, managed the engineering team, and worked with Product to bring requested features to life.

  • Arbitrage Bot

    The arbitrage bot found arbitrage opportunities across Curve, Balancer, and Uniswap and used Aave flash loans if possible.

    The smart contract code to perform the arbitrage was written in assembly to reduce gas costs.

    The bot was deployed on Ethereum, and a modified Geth node was used to allow the bot to listen for transactions in the mempool and submit arbitrage transactions in the same block.

  • Web3 Escrow Site

    The site allows the sale of locked tokens for the NFT game The front end is written in React, web3.js. A user can transfer his tokens to the escrow contract and set a price for which they can be bought. If someone buys the escrowed tokens, they are transferred to the buyer's wallet, and the purchase tokens are transferred to the seller's wallet.

  • Orica V2 Token

    Created the ERC20 Token with the following properties:
    • It had a configurable percentage that was taken from all token transfers and rewarded to all token holders. This was implemented using reflection, as implementing this with a loop would be unfeasible because of gas constraints.
    • It had a configurable percentage that was taken from all token transfers and deposited into a Uniswap type liquidity pool.
    • It allowed for addresses to be blacklisted, ownership to be transferred, and tokens to be burned.
    • The project was set up using Hardhat. Extensive tests were written and the Uniswap features were tested using a mainnet fork.
    • The project was configured to be deployable to Polygon Testnet and Mainnet


  • Languages

    Python, Ruby, JavaScript, TypeScript, Clojure, Scala, CSS, PHP, HTML, SQL, Solidity, Go, Rust
  • Frameworks

    Ruby on Rails (RoR), Django, Angular, Bootstrap, Flask, Jest, Spark, CakePHP, Play, Material-UI
  • Libraries/APIs

    React, Facebook API, Backbone.js, Pandas, Scikit-learn, jQuery, Node.js, Sidekiq, REST APIs, TensorFlow, PyTorch, Vue, Web3.js
  • Tools

    Jenkins, Jupyter, Apache JMeter, Jira, Terraform, Chef, Vim Text Editor, Slack, Asana, Trello, GitHub
  • Paradigms

    Agile, Test-driven Development (TDD), DevOps
  • Platforms

    Kubernetes, iOS, Ubuntu, Docker, Amazon Web Services (AWS), Blockchain, Ethereum, Blockchain Platforms, WordPress, Android, Google Cloud Platform (GCP), MacOS, Visual Studio Code
  • Storage

    PostgreSQL, MySQL, MongoDB, Redis, DB, Elasticsearch
  • Other

    AWS, Back-end, Leadership, Team Leadership, Crypto, Bitcoin, Smart Contracts, Non-fungible Tokens (NFT), Cryptocurrency, Ethereum Smart Contracts, APIs, Architecture, Technical Leadership


  • Bachelor's Degree in Computer Science, Computer Engineering
    2002 - 2007
    University of California, Davis - Davis, CA, United States


  • Sample-based Learning Methods
    MAY 2020 - PRESENT
  • Fundamentals of Reinforcement Learning
    MAY 2020 - PRESENT

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