Martin Bell
Verified Expert in Engineering
Data Engineering Developer
Glasgow, United Kingdom
Toptal member since June 24, 2020
Martin is a data professional with 15+ years of experience helping companies such as O’Reilly Media move from anecdotal decision making to driving strategies with data. He’s done almost everything in the data world; from building OLAP cubes, high-quality dashboards in Tableau or native Python to implementing business intelligence systems, and creating production-ready data pipelines in Apache Airflow. He is happiest working in PostgreSQL and Python but has also worked in MySQL and Oracle DB.
Portfolio
Experience
- SQL - 15 years
- Tableau - 10 years
- Data Engineering - 8 years
- Git - 8 years
- PostgreSQL - 8 years
- Python - 8 years
- Apache Airflow - 3 years
- Data Build Tool (dbt) - 1 year
Availability
Preferred Environment
Amazon Web Services (AWS), Jupyter, Git, Bash, PSQL, Linux
The most amazing...
...project I've built is infrastructure and code to provide analytics for 24-hour, real-time manufacturing production lines in Postgres, Airflow, dbt, and Tableau.
Work Experience
Manager, Data Engineering
Stonecrop Technologies
- Built and maintained a data warehouse on AWS PostgreSQL supporting analytics for a multi-million dollar logistics and manufacturing workflow.
- Developed ETL pipelines through Apache Airflow and dbt to Tableau to support near real-time analytics.
- Implemented new dbt instances for multiple clients allowing ETL version control and client-specific data transformation logic.
- Designed and implemented SOC compliant data governance processes to replace manual reporting and automate data entry workflows.
- Built Tableau Servers on AWS EC2 and administered the servers for internal teams and hundreds of external clients.
Data Consultant
Public Library of Science
- Led a Business Intelligence implementation for a major scientific publisher, modeling data to replace manual Excel reporting.
- Introduced version control and peer review, and trained developers in Git, Bash, and data warehouse modeling techniques.
- Provided reporting via SQL to replace previously manual Excel work and created backup scripts to ensure persistent data sources.
Insights and Analysis Lead
Safari Books Online/O'Reilly Media
- Created ETL pipelines with Python and SQL and modeled data in Mondrian schemas for a SAAS platform supporting 100,000+ users.
- Built KPI and user metric dashboards in Tableau and D3.js that offered insight into user behavior, reported on A/B tests and multivariate experiments.
- Guided the data science team with strategic direction, created analyses in R, and built a Shiny server so the team could publish work interactively.
Experience
Mobile Analytics E-book and Reporting MVP
I created an MVP data product that was used as a lead-generation tool. I ingested data from the Google Analytics API and an App Annie instance via Python ETL scripts running on Heroku and pushed them every few minutes into a dashboard that showed app performance and KPIs.
Skills
Libraries/APIs
Pandas, Matplotlib, D3.js
Tools
Apache Airflow, Tableau, Git, Jupyter, Jira, Mondrian, Sisense
Languages
SQL, Python, Bash, R
Platforms
Linux, Amazon Web Services (AWS), Pentaho, Windows
Storage
PostgreSQL, MySQL, Database Architecture, PSQL
Paradigms
ETL, Agile, Agile Product Management, Database Design
Frameworks
RStudio Shiny, Windows PowerShell
Other
Data Build Tool (dbt), Data Reporting, Data Analytics, Data Engineering, Data Warehousing, Data Warehouse Design, Data
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