Michael Kowalski, Developer in Brisbane, Queensland, Australia
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Michael Kowalski

Verified Expert  in Engineering

Software Developer

Location
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

Roaring Deep Pty Ltd
TypeScript, GraphQL, React, Vue, MongoDB, Test-driven Development (TDD)...
Cashwerkz Limited
JavaScript, Trading, Financial Markets, Finance, Fixed Income...
Bolder Group Pty, Ltd.
JavaScript, Node.js, Meteor, Cordova, iOS, Android, Xcode, App Store...

Experience

Availability

Part-time

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

2021 - PRESENT
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.
Technologies: TypeScript, GraphQL, React, Vue, MongoDB, Test-driven Development (TDD), Node.js, Workbox, Databases, CI/CD Pipelines, Pytest, Ionic, Full-stack Development, Minimum Viable Product (MVP), NoSQL, Responsive Design, Web & Mobile Applications, Back-end Development, Back-end Architecture, Software Architecture, User Experience (UX), User Interface (UI), OAuth, Single Sign-on (SSO), Docker, Kubernetes, Material UI, Tailwind CSS, Mongoose

Portfolio Manager

2015 - 2018
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.
Technologies: JavaScript, Trading, Financial Markets, Finance, Fixed Income, Derivative Pricing, Statistics, Research, Bloomberg API, APIs, Startups, Currencies, Data Analysis, Algorithms, Algorithmic Trading, Fintech, Financial Software, Banking & Finance, Agile, Writing & Editing, HTML5, Finance APIs, Quantitative Research, Software Development, Reverse Engineering, Data Analytics, Excel 2016, Data Engineering, Web Development, Databases, Google Sheets, Data, Data Processing, Investment Manager, Investments, Time Series Analysis

Developer

2014 - 2015
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.
Technologies: JavaScript, Node.js, Meteor, Cordova, iOS, Android, Xcode, App Store, Google Analytics, Mixpanel, MongoDB, SQL, Front-end Development, React, APIs, Startups, Architecture, Algorithms, Server-side Rendering (SSR), Handlebars, Test-driven Development (TDD), GitHub, REST APIs, Unit Testing, Jest, CSS, Agile, Mobile Development, Mobile, HTML5, NPM, Software Development, Hybrid Apps, Mobile App Development, Express.js, UI Design, Back-end, Automated Testing, Integration Testing, UI Development, Lint, Web Development, Databases, Data, Ionic, Full-stack Development, Minimum Viable Product (MVP), JSON REST APIs, NoSQL, Responsive Design, Cross-platform App Development, Web & Mobile Applications, Cross-platform, Back-end Development, Back-end Architecture, Software Architecture, User Experience (UX), User Interface (UI), OAuth, Single Sign-on (SSO)

Consultant

2013 - 2013
Private Contractor
  • Advised one of Australia's largest landfill management software providers on customer requirements of Carbon Emissions portfolio tracking.
  • Produced acceptance tests using Cucumber to guide development and confirm user interface features.
  • Researched regulatory schemes to ensure accurate calculations and business rules were implemented.
Technologies: Excel VBA, Cucumber, Financial Markets, Finance, Fixed Income, Derivative Pricing, Research, Web Applications, APIs, Data Analysis, Fintech, Financial Software, Commodities, Banking & Finance, Agile, Software Development, UI Design, Data Analytics, Web Development, Databases, Data, Minimum Viable Product (MVP), JSON REST APIs, Web & Mobile Applications, Software Architecture, User Experience (UX), User Interface (UI), Project Consultancy, Investments

Group Manager

2011 - 2012
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.
Technologies: JavaScript, Financial Analysis, Marketing, Trading, Financial Markets, Finance, Fixed Income, Derivative Pricing, Research, Web Applications, Currencies, Data Analysis, Algorithms, Commodities, Banking & Finance, Writing & Editing, Finance APIs, Quantitative Research, Data Analytics, Excel 2016, Google Sheets, Data, Microsoft Excel, Modeling, Investments, Time Series Analysis

Senior Contract Trader

2010 - 2011
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.
Technologies: Derivative Pricing, Fixed-income Derivatives, Trading, Financial Markets, Testing, Finance, Fixed Income, Statistics, Research, SQL, APIs, Data Analysis, Algorithms, Algorithmic Trading, Commodities, Banking & Finance, Writing & Editing, Finance APIs, Quantitative Research, Data Analytics, Data Modeling, Visual Basic for Applications (VBA), Excel 2016, Data Engineering, Databases, Data, Microsoft Excel, Modeling, Investments, Time Series Analysis

Manager

2006 - 2009
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.
Technologies: Python, Derivative Pricing, Fixed-income Derivatives, Financial Analysis, Trading, Financial Markets, Testing, Finance, Fixed Income, Statistics, Research, Bloomberg API, Architecture, Data Analysis, Algorithms, Fintech, Financial Software, Commodities, Banking & Finance, Writing & Editing, Finance APIs, Quantitative Research, Merchant Banking, Naive Bayes, Software Development, Reverse Engineering, Data Analytics, Data Modeling, Data Visualization, Excel 2016, Data Engineering, Databases, Data, Microsoft Excel, Modeling, Investment Manager, Investments, Time Series Analysis

Associate

2004 - 2004
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.
Technologies: Financial Analysis, Blogging, Marketing, Financial Markets, Finance, Fixed Income, Derivative Pricing, Bloomberg API, Web Applications, HTML, Startups, Currencies, Fintech, Financial Software, Investment Banking, CSS, Writing & Editing, HTML5, Merchant Banking, Web Development, Investments

Director of Business Development

2001 - 2003
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.
Technologies: Contract, Business Development, Financial Markets, Startups

Associate

1994 - 1998
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.
Technologies: C++, Derivative Pricing, Trading, Financial Markets, Testing, Finance, Machine Learning, Statistics, Research, Bloomberg API, SQL, Linux, Front-end Development, APIs, Architecture, Currencies, Data Analysis, Algorithms, Algorithmic Trading, Fintech, Financial Software, Commodities, Investment Banking, Banking & Finance, Writing & Editing, Finance APIs, Quantitative Research, Merchant Banking, Naive Bayes, Software Development, Reverse Engineering, UI Design, Data Analytics, Data Modeling, Data Visualization, Visual Basic for Applications (VBA), Excel 2016, Data Engineering, Databases, Data, Microsoft Excel, Modeling, Excel Macros, Data Processing, Investment Manager, Investments, Time Series Analysis, Visual Basic

Documentation Generation from GraphQL Schema

https://help.appdirect.com/api/graphql/index.html
I built a customized static website generator that received the federated GraphQL schema and produced a responsive static website containing the API documentation. I developed the site-building tool and the front-end UI. Project milestones varied from accessing the federated registry directly to moving from legacy Mustache.js templates to server-side React. I created a complete set of tests from scratch. These ranged from unit tests parsing the GraphQL schema to snapshot tests comparing site pages from a static schema.

Full-stack Game Development

A game involving decisions about faces built to gather research data for a large team of academics in economics, psychology, and machine learning. The deliverables consisted of:

• 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

The client was a fintech company with several successful services that wanted to launch a new mobile app for a new service idea. The deliverables were:

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-next
An RSS reader for browsing the news. I have used versions of it personally as a replacement for Google Reader since that service was discontinued in 2014. I am the only person involved in the project.

A 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

The application was a locality-based social network that allowed people to connect and plan events. I joined the project already in progress and implemented features such as iOS notifications using Firebase and completing the build process to get the app into TestFlight for testing.

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

An iOS and Android game built to help expecting parents choose a name. Along with a partner, I designed, developed, and marketed the game from concept to launch. The game was available for download for several years. It had hundreds of people playing daily and attracted 100,000+ downloads.

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-apis
I contributed pull requests and bug reports to TensorFlow, Swift for TensorFlow (S4TF), PyTorch, and other academic machine learning projects.

My 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-insert
A package for the Meteor JavaScript framework that makes inserting a large number of documents into MongoDB more efficient (100x improvement). The package maintains Meteor database security rules and enables Meteors' optimistic UI features for batch inserts from the client.

The package has been used by 5,000+ developers and has been maintained since 2015.

Hedge Improvement with Bucket Duration - Bank Research Project

The project asked whether carefully allocating a bond's duration risk across multiple buckets would improve hedging efficiency. Hedge efficiency means how accurately the price change of a portfolio matches the estimated change based on duration and yield change.

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

An iOS app that helps users tracks fitness goals. The app was available for a number of years in several countries through the App Store. A nice technical feature of the app was its animated page transitions while users were looking through graphs of their progress.
2005 - 2006

Master's Degree in Business Administration (MBA)

Oxford University - Oxford, UK

1990 - 1994

Bachelor's Degree in Business Administration

University of Michigan - Ann Arbor, Michigan, USA

NOVEMBER 2021 - NOVEMBER 2023

AWS Certified Cloud Practitioner

Amazon Web Services

FEBRUARY 2017 - PRESENT

Neural Networks for Machine Learning

Coursera/University of Toronto

JULY 2015 - PRESENT

Certified SuperForecaster

Good Judgment, Inc.

JULY 2014 - PRESENT

Practical Machine Learning

Coursera/Johns Hopkins University

JANUARY 2014 - PRESENT

Machine Learning

Coursera/Stanford University

DECEMBER 2012 - PRESENT

Web Intelligence and Big Data

Coursera/Indian Institute of Technology, Delhi

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

Frameworks

Jest, Tailwind CSS, Fastify, Express.js, Swagger, Ionic, Next.js, Remix, Material UI, Framework7, React Native, Laravel Mix, SwiftUI

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

Paradigms

Test-driven Development (TDD), Unit Testing, Mobile Development, Quantitative Research, UI Design, Automated Testing, Testing, Agile, Serverless Architecture, Data Science, 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, 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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