Daniel is available for hire

Daniel Henneberger

Verified Expert in Engineering

Back-end Developer

Location

Eugene, OR, United States

Toptal Member Since

November 17, 2020

For the past few years, Daniel has been working on enabling developers to build software faster and easier. He's developed novel query optimizers for NoSQL databases, created machine learning algorithms for big data in adtech, and built novel high-performance API gateways for databases. As a full-stack developer, Daniel has worked with many programming languages including, Java and GraphQL. He's also created foundational software for companies and managed small engineering teams.

Java NoSQL Cassandra Microservices GraphQL Machine Learning Natural Language Processing (NLP)Clustering Computer Vision Rust Open Source Python Dropwizard Spring Apache Velocity

Portfolio

Datakin

Apache Airflow, Microservices, Open Source, Dropwizard, OpenLineage, Python...

Datastax

Cassandra, NoSQL, Java

Oracle

Clustering, Generative Pre-trained Transformers (GPT)...

Experience

Java - 10 years NoSQL - 6 years Cassandra - 6 years Microservices - 6 years GraphQL - 2 years Rust - 2 years Machine Learning - 2 years GPT - 2 years

Availability

Part-time

Preferred Environment

Java

The most amazing...

...project I've worked on was developing a relational query engine on top of Cassandra.

Work Experience

Software Engineer

2020 - PRESENT

Datakin

Participated in the open-source development of the Marquez and Open Lineage project. Extended Marquez to provide additional operators for the Apache Airflow data pipeline tool.
Assisted in developing the OpenLineage specification for widespread adoption in data pipeline tools. Assisted with dataset versioning, run versioning, and job versioning concepts for data pipeline management aspects.
Applied data modeling expertise to provide scalable solutions for the database layer. Developed PostgreSQL table partition implementations for time series data.

Technologies: Apache Airflow, Microservices, Open Source, Dropwizard, OpenLineage, Python, Java

Senior Software Engineer

2018 - 2020

Datastax

Worked as a software engineer under DataStax's Chief Technologist to develop a new kind of data platform on top of the Cassandra database stack that would enable enterprises to quickly operationalize their data.
Developed a query optimizer on NoSQL databases to find minimal query plans given the schema, workload, and constraints; enabled the optimizer to receive inputs from the user about advanced data features to allow decisions beyond conventional optimizers.
Functioned as the sole back-end engineer for the SaaS platform until the team grew.
Developed several pieces of core functionality individually and with a small team.
Planned engineering work and delegated responsibilities.

Technologies: Cassandra, NoSQL, Java

Principal Software Engineer

2015 - 2018

Oracle

Worked as a full-stack software engineer for a big data analytics team. Developed new strategies for resolving data analytic queries faster. Created data pipelines for new data to enable Customer 360 applications.
Built applications for natural language processing, high dimensional clustering algorithms, search, and analytics. Assisted in the development of a novel distributed database to apply machine learning at scale.
Developed data visualization, microservice interaction tracing, and in-memory analytics to create actionable insights for developers and BI teams.

Technologies: Clustering, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), GPT, Machine Learning, Microservices, Java

Software Engineer

2014 - 2015

Mesoscale Discovery

Developed cloud-based laboratory management software for the biodefense, clinical, and life-science markets.
Implemented data-driven procedures for automated reagent dispensing systems and codified validated protocols for micro-plate test kits.
Developed highly tested and documented software consistent with FDA regulated software systems.

Technologies: Amazon Web Services (AWS), Biotechnology, Java

Graduate Assistant

2011 - 2013

Frostbug State University

Assisted in teaching and held labs for the computer science department. Lectured, developed course material, and mentored students.
Led students in computer science-related extracurricular activities, including computer security competitions, recruitment efforts, and other department software projects.
Administered the computer science GRE subject test.

Technologies: Java, Education

Applications Engineer

2010 - 2011

Micropact

Developed flagship java business process management software for the Department of Justice (DOJ) and the Internal Revenue Service (IRS) in a proprietary Java J2EE framework.
Worked on-site for the IRS to collect business requirements and independently developed several small Java projects.
Held public trust and secret security clearances for DOJ and IRS.

Technologies: Apache Velocity, Spring, Java

Web Developer

2008 - 2010

Concept C Marketing & Design

Constructed a WordPress website for a hair salon to highlight their products and provide location-aware pricing; building the site WordPress allowed the owner to implement changes.
Developed a website for a mall to provide a directory of stores and highlight winter promotions.
Worked closely with designers to assure that designs could be quickly created.

Technologies: WordPress, PHP, Java, Foundation CSS

Experience

GraphQL NoSQL Query Optimizer

https://github.com/henneberger/dbcompiler

A NoSQL query optimizer that works with an annotated GraphQL schema to create an optimized database schema. It features time-series compatibility and allows the ordering by date, immutable fields, including fields that span relationships.

Skills

Languages

Java, GraphQL, Rust, Python, PHP

Paradigms

Microservices

Storage

NoSQL, Cassandra

Frameworks

Dropwizard, Spring, Apache Velocity, Foundation CSS

Tools

Apache Airflow

Platforms

WordPress, Amazon Web Services (AWS)

Other

Data Structures, Machine Learning, Computer Vision, Natural Language Processing (NLP), Clustering, OpenLineage, Open Source, Biotechnology, Education, GPT, Generative Pre-trained Transformers (GPT)

Education

2011 - 2013

Master's Degree in Computer Science

Frostburg State University - Frostburg, MD, United States

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