Zach Boldyga, Developer in Seattle, WA, United States
Zach is available for hire
Hire Zach

Zach Boldyga

Verified Expert  in Engineering

Software Developer

Location
Seattle, WA, United States
Toptal Member Since
June 4, 2018

Zach’s abilities are best captured through his recent, six-year founding and management of Scalabull, a software company that currently powers over 1 million patient lab testing transactions in the US annually. Zach has also helped build open-source software since 2008, with recent projects including Tensorflow, Apache MXNet, and React.js components.

Portfolio

Scalabull
MySQL, CouchDB, Ruby, React, Meteor, ZeroMQ, NSQ.io, Redis, Elasticsearch...
TerraClear
TypeScript, PostgreSQL, Node.js, Amazon S3 (AWS S3), Amazon EC2...
RxNT
C#.NET, VB.NET, Ruby, JavaScript

Experience

Availability

Part-time

Preferred Environment

Databases, TensorFlow, Python, JavaScript, Linux

The most amazing...

...thing I've done is found Scalabull, a backbone of the US healthcare infrastructure.

Work Experience

Founder | CTO

2013 - PRESENT
Scalabull
  • Architected and managed a technology stack with over 150 microservices; implemented over 100 of the microservices.
  • Built a platform for submitting and receiving medical data to/from hospitals, physician's offices, and laboratories in a variety of formats—resulting in guaranteed real-time message delivery.
  • Leveraged millions of healthcare data points to implement machine learning tools that optimize workflows and provide non-trivial insights.
  • Ensured that HIPAA security best-practices are used throughout the organization.
  • Managed four different product teams over the company lifespan. In chronological order: Built a data warehouse, completed Quest Diagnostics & LabCorp certified integrations, built a cloud-based platform for interface management, developed machine learning APIs.
Technologies: MySQL, CouchDB, Ruby, React, Meteor, ZeroMQ, NSQ.io, Redis, Elasticsearch, MongoDB, Rust, Node.js, Scikit-learn, TensorFlow, Jupyter Notebook, Python

Software Engineering Contractor

2018 - 2019
TerraClear
  • Served as a stopgap in an early-stage startup while the founders searched for dedicated employees. Discussions with the team spanned machine learning, software engineering, and DevOps strategies.
  • Developed a pipeline to incorporate machine learning into the flagship application.
  • Worked with an all-star cast of tech industry veterans. I learned a lot and was able to provide value in a time of need.
  • Leveraged the AWS ecosystem, with loose coupling for optionally switching to locally-hosted solutions or other vendors.
  • Built command line tools for submitting and monitoring ML jobs.
  • Developed an open source service mesh that we forked internally; all of it was done during the course of the above work.
Technologies: TypeScript, PostgreSQL, Node.js, Amazon S3 (AWS S3), Amazon EC2, Relational Database Services (RDS), Amazon Simple Queue Service (SQS), AWS Lambda

Seasonal Software Engineering Intern

2008 - 2012
RxNT
  • Developed a TWAIN driver for electronic signature processing.
  • Created tools for processing messy text data.
  • Implemented rudimentary web applications for marketing and internal use.
  • Fixed bugs in the production application.
  • Helped implement new features in the production application.
Technologies: C#.NET, VB.NET, Ruby, JavaScript

Implementation of Conv3d for TensorFlow.js

https://github.com/tensorflow/tfjs-core/pull/1238
I implemented 3D convolutions for TensorFlow.js:
• https://github.com/tensorflow/tfjs

TensorFlow is written in C++ and CUDA and exposes a C API which is then called by other, easier-to-use languages like Python. For nearly all programming languages, using TensorFlow simply means building a client library by writing some wrapper code around the C API.

However, enabling a tool like TensorFlow to run via JavaScript in a web browser is a bit different. With WASM, it's technically possible to run this C++/CUDA code in the browser. But as of 2019, the practical approach to doing inferencing and training of machine learning models inside of a web browser is to use a tool like TensorFlow JS: a from-scratch implementation of TensorFlow's C++ and CUDA code, instead of being written in TypeScript and WebGL.

That said building TensorFlow JS means rebuilding all of the components of a machine learning library from scratch. Aiding in this effort, I built in the ability for this library to handle 3D convolutions that are commonly used in video and time series applications.

This technology currently powers web-based 3D medical image segmentation tools, video effects, and more!

Predicted Delivery Times for Lab Results

US lab results contain a number of timestamps (always including the original time the test was ordered, and the time the testing was completed and when the result was sent to the patient). Using millions of these examples, a neural-network-based regression model was trained to predict when the ordered test results will be delivered to patients.

If a physician orders a TSH panel from Quest Diagnostics—due to the fact that we've seen over 50,000 of those transactions—our system has quality information to assess when the result will be returned. While relying on deep learning allowed us to avoid complex feature extraction in this implementation, the initial implementation used multivariate linear regression and required feature extraction. Therefore, it's clear that the neural network relies on information like the day of the week and time of day the test was ordered, the type of test, the age of the patient, and the lab and/or region of the US.

This is currently considered proprietary; the code is not included.

Patient Record Deduplication

Over 1 million patients receive lab results through our system annually, e.g., the results of their blood tests.

In this set of data from laboratories, radiology providers, and hospitals, we experience considerable misinformation. Patient names are misspelled, dates of birth are incorrect or missing, and patient IDs are jumbled or missing.

Generally, a human—your doctor or their staff—will notice and fix this error. But this data corruption prevents the automated matching of patient records into patient charts and can prolong the time it takes for a patient to receive care.

The code seen here is one of the few mechanisms we use to tackle this problem. Machine learning (basic logistic regression), clever string distance metrics, predicate blocking, an inverted index, Chavatal's greedy set cover algorithm, and hierarchical clustering with centroid linkage are all used to create an intuitive patient record correction system that automatically fixes over 90% of corrupted data we receive.

100+ Scalabull Applications

I architected, built, and performed DevOps for over 100 of the microservices that power Scalabull.

Includes:
• An entire, medical-grade data warehouse.
• User-facing platforms built with React, Meteor, chart.js
• REST APIs
• Generation of a variety of clinically-approved PDF formats with conditionally changing layouts and barcodes.
• Integration into SOAP web services provided by Quest Diagnostics and LabCorp.
• Created more than 1,000 HL7 interfaces.Live connections between doctors and clinical laboratories.
• MLLP server and client.
• In-house SFTP server and client.
• Machine learning tools with production-grade deployments.
• ZeroMQ, Redis, and NSQ used for various messaging and key/value store needs.
• Elasticsearch for information discovery.
• Nagios to track system failures and provide real-time alerts to developers.
• A fault-tolerant infrastructure with combined hardware firewalls, dedicated servers, and cloud servers.

MxNet Contributions

https://github.com/apache/incubator-mxnet/
My contributions to Apache MXNet have revolved around expanding the maths library capabilities and documentation.

React JSON-schema Form Ecosystem

https://github.com/RxNT/react-jsonschema-form-conditionals
I orchestrated and contributed to the development of multiple open-source extensions to the React JSON-schema Form, a utility for creating user input forms from a JSON schema object on-the-fly. Our plugins allow users to significantly enhance this tool and create enterprise-grade forms from JSON-based configurations.

The projects include:
• Extras: an assortment of fancy widgets (e.g., typehead text fields).
- https://github.com/RxNT/react-jsonschema-form-extras
• Pagination: multipage forms are supported.
- https://github.com/RxNT/react-jsonschema-form-pagination
• Conditionals: a rules engine can be applied to compute values in the form, hide form fields, and manipulate form CSS.
- https://github.com/RxNT/react-jsonschema-form-conditionals
• Form Manager: This makes it simpler to plug all of our utilities together into an enterprise-grade application.
- https://github.com/RxNT/react-jsonschema-form-manager

Languages

JavaScript, TypeScript, Python 3, Rust, Python, Ruby, VB.NET, C#.NET, C, Java

Frameworks

MXNet

Libraries/APIs

TensorFlow, Scikit-learn, NumPy, React, Node.js, NSQ.io, ZeroMQ

Paradigms

Functional Programming, Object-oriented Programming (OOP), Gang of Four (GOF) Design Patterns

Platforms

Jupyter Notebook, Linux, Amazon Web Services (AWS), Meteor, AWS Lambda, Amazon EC2, Rackspace

Other

Machine Learning, Front-end Development, NixOS, Relational Database Services (RDS)

Tools

Amazon Simple Queue Service (SQS)

Storage

MongoDB, CouchDB, PostgreSQL, Databases, Elasticsearch, Amazon S3 (AWS S3), Redis, MySQL

2018 - 2018

Completed the Program in Alternative MBA Studies

altMBA - Online (Altmba.com)

2008 - 2011

Bachelor of Science Degree in Computer Science

University of Maryland, College Park - College Park, MD, USA

FEBRUARY 2019 - PRESENT

Deep Learning Specialization

Coursera

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

1

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.
2

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.
3

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring