Michael Kowalski
Verified Expert in Engineering
Software Developer
Brisbane, Queensland, Australia
Toptal member since May 3, 2021
Michael has an exceptional background in finance, business, and software. He is a certified SuperForecaster and MBA with knowledge of machine learning. At Credit Suisse, he produced $24 million in profit using bespoke software tools to identify statistical arbitrage transactions in the sovereign bonds of 20 countries and built a yield curve-based pricing model for Australian Bank Hybrid Bonds. Michael has industry experience in finance, energy, telecommunications, and publishing.
Portfolio
Experience
- Finance - 15 years
- Node.js - 9 years
- Machine Learning - 9 years
- Git - 9 years
- Python - 7 years
- React - 7 years
- TypeScript - 5 years
- Swift - 3 years
Availability
Preferred Environment
Python, React, Swift, GraphQL, TypeScript, Test-driven Development (TDD), Algorithms, Fintech, Financial Software, Git
The most amazing...
...product I have developed is a portfolio management tool tailored to very specific metrics that was relied on daily for several years.
Work Experience
Developer
Roaring Deep Pty Ltd
- Developed multiple mobile apps and websites across different projects and clients.
- Wrote a business plan and a mobile app specification (including backend stack and database schema) for a consumer fintech idea.
- Automated production of GraphQL API documentation for a large B2B commerce company.
Portfolio Manager
Cashwerkz Limited
- Created algorithms to mimic the performance of popular actively-managed bond funds by analyzing historic fund and index returns.
- Developed a yield curve-based pricing model in JavaScript and Node.js for Australian Bank hybrid bonds.
- Built a budget reporting and forecasting tool to track business progress in weekly meetings.
Developer
Bolder Group Pty, Ltd.
- Refactored client code of the Two Fat Guys app so that user actions and screen transitions had immediate (less than 300ms) results.
- Designed and developed the Baby Name Game from the idea stage to an iOS and Android app for sale for several years in many countries. The app was a Single Page JavaScript app served to clients by Node.js using MongoDB for storage.
- Maintained apps following release with smooth database, server, and version migrations.
Group Manager
Ecofund Queensland
- Achieved record carbon and renewable energy transactions revenue and profits by focusing on large, specialized transactions and customer acquisition.
- Automated public data gathering to produce daily reports on supply and demand with JavaScript and Node.js.
- Oversaw the launch of hedging products tailored to Australia's emissions trading scheme.
Senior Contract Trader
Stanwell
- Transacted electricity forwards and Renewable Energy Credits (RECs) to meet hedging and risk management policies.
- Aggregated and profit tracking for Renewable Energy Certificates (RECs) with an Excel front end that linked to an SQL transaction database.
- Executed the company's largest electricity transaction that year through negotiations with a key customer. The transaction required and received special board approval due to its size and complexity.
Manager
Macquarie
- Enabled bespoke transaction booking for a new business through Python scripts representing details.
- Designed and oversaw the customization of existing accounting, valuation, and risk management systems to accommodate environmental commodities.
- Valued the bank's first carbon credit forward transaction using a Monte Carlo simulation of electricity production from a newly built Chinese power plant.
Associate
Minyanville Publishing and Multimedia
- Provided real-time market commentary with several publishing tools.
- Reduced 90% of publishing platform costs by identifying external providers through a review of competitors and industry practices.
- Identified marketing opportunities through trackbacks and partnerships with prominent market and economic bloggers.
Director of Business Development
CyberBazaar India
- Coordinated with the team in India to verify teleconference call quality. The data collected was used to identify fraudulent billing of Internet Protocol long-distance calls at voice calling rates.
- Developed business partnerships resulting in a competitive bidding process and acquisition by WebEx Communications for $4 million.
- Established dedicated international phone and data pipelines as a new product category through a new partnership.
Associate
Credit Suisse
- Wrote C/C++ tools for time series analysis and position tracking.
- Produced $24 million in profit using bespoke software tools to identify statistical arbitrage transactions in the US sovereign bonds of 20 countries.
- Tested and approved new firm-wide fixed income software that streamlined data collection and reporting. The databases and calculation engines enabled further automation of transaction confirmations and position reporting.
Experience
Automated Documentation Generation from GraphQL Schema
https://help.appdirect.com/api/graphql/index.htmlPROBLEM
AppDirect moved to a GraphQL API, requiring a brand new documentation site for its customers.
MY CONTRIBUTIONS
I enhanced the project by adding automated testing, implementing interactive examples, and converting Mustache templates to React, modernizing the codebase. I also contributed by fixing bugs, adding new features, and optimizing the system using my TypeScript, Node.js, React, and GraphQL skills.
OUTCOMES
The site generation worked flawlessly, enabling the new API to be documented publicly to speed up customer adoption. With little change, the site will continue as the primary resource for API users in 2024.
Full-stack Game Development
• React responsive web app allowing basic profile management and fast gameplay.
• Node.js back-end with WebSocket data synchronization to the client and a REST API to connect with an AI player microservice.
• Automated end-to-end tests using Playwright. Automated unit and integration tests using Mocha and Sinon.JS.
• GitLab CI/CD enables multiple separate instances of the site to run for data gathering and feature testing.
• MongoDB Atlas charts to visualize collected data.
Product Management - Business Planning and Design for a Fintech Mobile App
1) A business plan outlining competitors approaches, market segments, and a business model;
2) A specification for the app with front-end designs in Figma, a database schema, and back-end API documentation in OpenAPI;
3) Initial code for the app with TypeScript/React Native, AWS back-end APIs, and AWS CloudFormation scripts to run CI/CD.
RSS Reader
https://github.com/mikowals/simple-rss-nextA current back end uses Cloudflare's serverless workers to provide a GraphQL API. All state is kept in a key value store. The total response time to a client is around 100ms for queries, while mutations that require polling RSS feeds are bottlenecked by the slowest feed response.
Front ends have been made in React and Next.js, React Native, and Swift UI. In each implementation, the UI is optimistic, with Apollo's client cache reflecting user actions across the entire app immediately. iOS implementations have features like pull-to-refetch latest articles on the 'News' page and slide-right to delete a subscribed feed on the 'Subscriptions' page.
The back end can be browsed at https://worker-rss.mikowals.workers.dev/__graphql with the code repository at https://github.com/mikowals/cloudflare-worker-rss.
The React Native front end for iOS is at exp://exp.host/@mikowals/rss-react-native.
The code repository for the React and Next.js is at https://github.com/mikowals/simple-rss-next. It is not currently running anywhere.
React and Node.js Neighborhood Network and Chat iOS App
I also did several rounds of bug fixes for the app. For example, the chat features would lose messages, so I debugged the Websocket connection implemented in socket.io to eliminate the problem.
The app will be released in the App Store shortly.
Baby Name Game
Requirements:
• MongoDB database to host names, customer data, and game state.
• A single-page application wrapped for iOS and Android store downloads.
• Hosting with release and version migration scripts on the Meteor platform and DigitalOcean.
Game features:
• Freemium model progressing from anonymous play to paid customer.
• Joint play with a secure invite system shared data between linked players.
• Responsive UI for multiple phone and tablet sizes.
• Fast game play with optimistic server interactions and user milestone updates.
• Analytics and reporting interface to track usage and progress through an upgrade cycle.
• Available in multiple countries with geographically appropriate names.
Machine Learning Open Source Contributions
https://github.com/tensorflow/swift-apisMy contributions focused on implementing high-level machine learning algorithms, but given the newness of the software, this often led to fixing framework bugs. For example, I had pull requests accepted for TensorFlow and Swift for TensorFlow to fix their respective implementations of batch normalization. The fix in TensorFlow corrected the application of different averages for training versus inference, while the fix in S4TF corrected the automatic derivative calculation for a square root.
Batch Insert—Meteor Package
https://github.com/mikowals/batch-insertThe package has been used by 5,000+ developers and has been maintained since 2015.
Hedge Improvement with Bucket Duration - Bank Research Project
Working in C and C++, I built a back-testing harness and point-in-time model to produce the historic ratios for trades hedged with standard and bucket durations. Backtesting could report the daily standard deviation of realized profit from expected profit.
The project discovered that the firm's treasury curve model had a computational quirk where minor price changes could cause the curve to "pop" between curling up and curling down. The effect of this quirk on hedge efficiency was three times larger than the duration effects originally studied.
This inefficiency was fixed by adding an extra step to the treasury model that forced the curve to pass through the on-the-run (most liquid) bond yields.
Two Fat Guys
Education
Master's Degree in Business Administration (MBA)
Oxford University - Oxford, UK
Bachelor's Degree in Business Administration
University of Michigan - Ann Arbor, Michigan, USA
Certifications
AWS Certified Cloud Practitioner
Amazon Web Services
Neural Networks for Machine Learning
Coursera/University of Toronto
Certified SuperForecaster
Good Judgment, Inc.
Practical Machine Learning
Coursera/Johns Hopkins University
Machine Learning
Coursera/Stanford University
Web Intelligence and Big Data
Coursera/Indian Institute of Technology, Delhi
Skills
Libraries/APIs
React, Node.js, Bloomberg API, Handlebars, REST APIs, Mustache, PyTorch, TensorFlow, Sinon.JS, Vue, Vuex, CocoaPods, OpenAPI, Puppeteer, Playwright, Chart.js, Socket.IO, AWS Amplify
Tools
Xcode, NPM, GitHub, GitLab, GitLab CI/CD, Excel 2016, Google Sheets, Microsoft Excel, Mongoose, Git, Webpack, MATLAB, MongoDB Atlas, Workbox, Cucumber, Google Analytics, CodeMirror, AWS CloudFormation, AWS CodeCommit, AWS CodeBuild, Figma, Mocha, Pytest
Languages
Python, JavaScript, Excel VBA, GraphQL, SQL, CSS, TypeScript, Python 3, Python 2, Visual Basic for Applications (VBA), ECMAScript (ES6), Visual Basic, Swift, Octave, C++, HTML, SCSS, HTML5, R, Swift 5
Frameworks
Jest, Tailwind CSS, Fastify, Express.js, Swagger, Ionic, Next.js, Remix, Material UI, Framework7, React Native, Laravel Mix, SwiftUI
Paradigms
Test-driven Development (TDD), Unit Testing, Mobile Development, Quantitative Research, UI Design, Automated Testing, Testing, Agile, Serverless Architecture, Acceptance Testing, Continuous Deployment, Continuous Integration (CI), Cross-platform, Back-end Architecture, MapReduce, REST
Platforms
Linux, Meteor, Mobile, Firebase, iOS, Amazon Web Services (AWS), Android, Google Cloud Platform (GCP), Docker, Mailgun, DigitalOcean, Amazon EC2, Mixpanel, AWS ALB, Kubernetes
Industry Expertise
Accounting, Banking & Finance, Marketing
Storage
MongoDB, NoSQL, JSON, Databases, MySQL, Amazon S3 (AWS S3)
Other
Finance, Strategy, Financial Analysis, Statistics, Research, Derivative Pricing, Fixed-income Derivatives, Fixed Income, Blogging, Full-stack, Web Applications, Back-end, Front-end, Trading, Financial Markets, Front-end Development, Startups, Currencies, Data Analysis, Fintech, Financial Software, Merchant Banking, Investment Banking, Commodities, Writing & Editing, RSS Feeds, Finance APIs, Software Development, Mobile App Development, UI Development, i18n, Data Analytics, Data Modeling, Data Visualization, Data Engineering, Web Development, Data, Modeling, Full-stack Development, Minimum Viable Product (MVP), JSON REST APIs, Responsive Design, Excel Macros, Cross-platform App Development, Web & Mobile Applications, Back-end Development, Software Architecture, User Experience (UX), User Interface (UI), OAuth, Single Sign-on (SSO), Investment Manager, Investments, Time Series Analysis, Zustand, Venture Capital, Organizational Design, Machine Learning, Contract, APIs, Cloudflare, Responsive UI, App Store, Mobile Apps, Architecture, Algorithms, Algorithmic Trading, Server-side Rendering (SSR), Lint, Serverless, Mobile UI, Apollo, Apollo Server, Logistic Regression, Linear Regression, Classification Algorithms, Predictive Modeling, Data Science, Naive Bayes, Hybrid Apps, Reverse Engineering, Linear Algebra, Artificial Intelligence (AI), Product Management, Database Schema Design, Integration Testing, Service Workers, CI/CD Pipelines, Project Consultancy, Data Processing, AWS App Runner, Vite, Business Development, Optimistic UI, WebSockets, Cordova, Random Forests, GPU Computing, Image Recognition
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