William Leslie Theisinger, Developer in Los Angeles, CA, United States
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William Leslie Theisinger

Verified Expert  in Engineering

Bio

William has deep experience in all aspects of data-related initiatives—from data design, architecture, and development to data management, strategy, and product and project management. He has designed, architected, and implemented data platforms and re-engineered and refactored existing data systems. William is fully autonomous and can work with teams or as an individual contributor. He also has experience in GCP, AWS, and on-premise and remote data centers.

Portfolio

Paramount Commerce
Google Cloud Platform (GCP), Amazon Web Services (AWS), GitHub Actions...
FloSports
Amazon Web Services (AWS), Informatica ETL, Dell Boomi, Talend ETL...
System1
Python, Apache Kafka, Data Build Tool (dbt), Snowflake...

Experience

  • Data Warehousing - 20 years
  • Data Engineering - 20 years
  • Data Warehouse Design - 20 years
  • ETL - 20 years
  • Data Architecture - 20 years
  • SQL - 20 years
  • Data Modeling - 15 years
  • CI/CD Pipelines - 7 years

Availability

Part-time

Preferred Environment

Visual Studio Code (VS Code), Slack, GitHub, GitHub Actions, MacOS, Google Cloud Platform (GCP), Amazon Web Services (AWS), Kubernetes, Python

The most amazing...

...thing I've developed is a full event-based modern data stack that maintained a 99.99% uptime.

Work Experience

Data Architect | Data Engineer

2023 - 2024
Paramount Commerce
  • Migrated the core data processing stack from AWS to GCP.
  • Completed a full CI/CD implementation using Airflow (Composer), dbt, Docker, Terraform, and GitHub Actions.
  • Created documentation for the run book, handoff, and training.
Technologies: Google Cloud Platform (GCP), Amazon Web Services (AWS), GitHub Actions, Google BigQuery, Google Cloud Composer, Data Build Tool (dbt), CI/CD Pipelines, Data Architecture, Data, Technical Leadership, Data Engineering, PostgreSQL, ETL, Apache Spark, Big Data, Software Development Lifecycle (SDLC), Column-oriented DBMS, Analytics, Business Intelligence (BI), Distributed Databases, Data Product Manager, Agile Project Management, Business Requirements, Data Warehousing, Analytical Thinking, Data Modeling, Data Governance, Business Analysis, Unix, Data Analysis, Data Pipelines, Docker, Terraform

Data Management Consultant

2023 - 2023
FloSports
  • Handled evaluation and recommendations for a data governance program based on the company maturity of data management, including the sequence, timing, and milestones for progression to full data maturity.
  • Evaluated numerous data governance vendors in various Gartner quadrants and newcomers in the space and recommended the implementation of different governance capabilities using services within AWS.
  • Provided detailed recommendations for implementing any chosen vendor and tradeoffs versus homebuilt alternatives.
Technologies: Amazon Web Services (AWS), Informatica ETL, Dell Boomi, Talend ETL, Data Architecture, Data, Data Engineering, ETL, Big Data, Software Development Lifecycle (SDLC), Business Intelligence (BI), Data Product Manager, Business Requirements, Data Warehousing, Analytical Thinking, Data Modeling, Data Management, Data Governance, Data Quality Governance, Business Analysis, Unix, Data Analysis

VP, Data Engineering

2021 - 2023
System1
  • Collaborated with the team to create new APIs that supported external partner reporting and data.
  • Initiated the migration to an event-based system to leverage in-stream processing on Kafka.
  • Created plans to ensure GDPR, CCPA, CPRA, and PII/non-PII compliance across all systems and data platforms.
  • Increased productivity by 30% by establishing a project planning process that aligned team focus on more throughput.
  • Managed and maintained the data platform through numerous acquisitions.
Technologies: Python, Apache Kafka, Data Build Tool (dbt), Snowflake, Amazon Web Services (AWS), Apache Airflow, Data Architecture, Consumer Data Platform, Technical Leadership, Data, Data Engineering, PostgreSQL, ETL, Big Data, Software Development Lifecycle (SDLC), Column-oriented DBMS, Analytics, Business Intelligence (BI), Distributed Databases, Data Product Manager, Agile Project Management, Data Warehousing, Analytical Thinking, Data Modeling, Data Management, Data Governance, Data Quality Governance, Unix, Data Analysis, Data Pipelines, Docker

Data Architect Consultant

2020 - 2021
Procore
  • Oversaw the design, architecture, and scaling of a new enterprise data platform, including development and engineering tasks and owning the product manager and product owner roles in the Agile development and requirements process.
  • Collaborated with the internal team to develop a platform on AWS, leveraging EKS, EMR, Spark, and Airflow for workflow management and various serverless components combined to manage orchestration.
  • Evaluated internal talent at the request of management and provided input to senior leadership, resulting in staffing team for impending IPO.
Technologies: Amazon Web Services (AWS), Amazon Elastic MapReduce (EMR), Spark, Data Build Tool (dbt), Looker, Apache Airflow, Amazon EKS, Data Architecture, Data, Data Engineering, PySpark, ETL, Apache Spark, Big Data, Software Development Lifecycle (SDLC), Column-oriented DBMS, Analytics, Business Intelligence (BI), Distributed Databases, Data Product Manager, Agile Project Management, Business Requirements, Data Warehousing, Analytical Thinking, Data Modeling, Data Governance, Unix, Data Analysis, Data Pipelines, Docker, Terraform

CTO

2018 - 2019
LERETA
  • Developed architecture and project plan to move from an on-prem data center to a hybrid model of cloud (GCP) and colocation facility.
  • Tasked with digital transformation, platform modernization, and consolidation that enabled adaptability to changing market conditions at a reduced cost. Supported over 30% YoY growth.
  • Designed and architected a complete plan to migrate from the legacy platform of IBM Mainframe VSe, VFP, Delphi, MSSQL13, Cobol, Natural, DYL280, and JCL to Google Cloud services, Go, JavaScript, Vue, Node.js, and Python.
  • Participated in the executive team reporting to the CEO. Worked closely with the BOD (Tarsadia Investments), regularly presenting technology road map, product management vision, project plans, and budget.
  • Managed a complete technology P&L—15 million in operating expenses (OPEX) and varying capital expenditures (CAPEX).
Technologies: Google Cloud Platform (GCP), Technical Leadership, Data Engineering, Software Development Lifecycle (SDLC), Agile Project Management, Analytical Thinking, Unix

VP, Data Platform Engineering & Data Science

2010 - 2017
YP
  • Designed, architected, and implemented a system re-platforming effort to move from a Microsoft data platform to a lightweight event system data collection, Hadoop processing, and Vertica.
  • Handled the design, implementation, and maintenance of 1,100 servers across 12 clusters with 99.99% uptime that never missed SLA and housed seven petabytes, ensuring 24/7 data availability.
  • Delivered a multichannel data collection framework in Kafka, supporting streams of up to 20,000 messages per second.
  • Processed 3+ billion daily transactions on the platform, which generated 3+ terabytes of data per day.
Technologies: Java, Spark, Apache Kafka, Vertica, Hadoop, Elasticsearch, SQL, Data Architecture, Consumer Data Platform, Technical Leadership, Data, Data Engineering, PostgreSQL, PySpark, ETL, Apache Spark, Big Data, Software Development Lifecycle (SDLC), Column-oriented DBMS, Analytics, Business Intelligence (BI), Distributed Databases, Data Product Manager, Agile Project Management, Business Requirements, Data Warehousing, Analytical Thinking, Data Modeling, Data Management, Data Governance, Business Analysis, Unix, Data Analysis, Data Pipelines

Manager, Strategic Data Services

2000 - 2005
Yahoo!
  • Designed, developed, tested, and deployed several new table structures and ETL processes using Unix shell scripting, Perl, and SQL to support the business's data needs.
  • Integrated SOAP-based XML API with the business operations group to provide a scalable reporting solution for that business team.
  • Managed the reporting needs for Yahoo Search Marketing, which required communication company-wide. Worked very closely with product marketing, product management, sales, business operations, and technology teams in the US and abroad.
Technologies: Oracle, Data, Data Architecture, Data Collection, Data Integration, BI Reporting, Data Warehousing, Data Warehouse Design, Technical Leadership, Data Engineering, ETL, Big Data, Software Development Lifecycle (SDLC), Column-oriented DBMS, Analytics, Business Intelligence (BI), Distributed Databases, Agile Project Management, Analytical Thinking, Data Modeling, Unix, Data Analysis, Data Pipelines

Experience

Prediction Platform for Real Estate Transactions

Built a machine learning predictive model platform on GCP in the real estate space. I handled the entire production flow, including data ingestion, pipeline development, data modeling, feature creation, and transformations such as normalization, scaling, and encoding. The flow also included extraction and selection, BigQuery and dbt for data processing, Vertex AI for MLOps, and various models to satisfy specific use cases in the real estate sector.

ETL Platform Using Spark and EMR

Designed and developed an entire ETL processing pipeline on AWS EMR using Spark, pushing data to a column-oriented MPP system, Redshift. The spark jobs were built to process data and funnel it through a rules engine to ensure the business data was valid. I interviewed all stakeholders, built a project plan, defined the requirements, and provided the technical documentation.

Education

2000 - 2003

Bachelor's Degree in Economics

California State University, Los Angeles - Los Angeles, CA, USA

Skills

Libraries/APIs

PySpark, Scikit-learn, Pandas

Tools

GitHub, Slack, Google Cloud Composer, Apache Airflow, Amazon Elastic MapReduce (EMR), Informatica ETL, Talend ETL, Looker, Amazon EKS, Cloud Dataflow, Terraform

Languages

SQL, Python, Snowflake, Java

Paradigms

Business Intelligence (BI), ETL, Agile Project Management

Platforms

Visual Studio Code (VS Code), Google Cloud Platform (GCP), MacOS, Amazon Web Services (AWS), Kubernetes, Apache Kafka, Oracle, Unix, Docker

Storage

Data Integration, Data Pipelines, Column-oriented DBMS, Distributed Databases, Vertica, PostgreSQL, Dell Boomi, Elasticsearch

Frameworks

Spark, Hadoop, Apache Spark

Other

Data Architecture, Data Management, Big Data, Data Engineering, Software Development Lifecycle (SDLC), Data Warehouse Design, Data Product Manager, Business Analysis, Data Modeling, Data Warehousing, Analytical Thinking, Technical Leadership, Data, Data Analysis, GitHub Actions, Google BigQuery, Data Build Tool (dbt), Analytics, CI/CD Pipelines, Data Governance, Data Quality Governance, Business Requirements, Consumer Data Platform, Machine Learning Operations (MLOps), Statistics, Economics, Data Collection, BI Reporting, Data Processing

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