Martin Bell, Developer in Glasgow, United Kingdom
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Martin Bell

Verified Expert  in Engineering

Data Engineering Developer

Location
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.

Data ReportingData AnalyticsData EngineeringSQLLinuxTableauPostgreSQLApache AirflowData WarehousingData Warehouse DesignETLPythonGitAgileJira

Portfolio

Stonecrop Technologies
Tableau, Git, Bash, Data, Apache Airflow, PostgreSQL
Public Library of Science
Windows PowerShell, Windows, Git, Bash, SQL, Sisense
Safari Books Online/O'Reilly Media
D3.js, RStudio Shiny, R, Tableau, Pentaho, Mondrian, PostgreSQL, Python

Experience

SQL - 15 yearsTableau - 10 yearsPython - 8 yearsGit - 8 yearsData Engineering - 8 yearsPostgreSQL - 8 yearsApache Airflow - 3 yearsData Build Tool (dbt) - 1 year

Availability

Part-time

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

2016 - 2020
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.
Technologies: Tableau, Git, Bash, Data, Apache Airflow, PostgreSQL

Data Consultant

2016 - 2016
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.
Technologies: Windows PowerShell, Windows, Git, Bash, SQL, Sisense

Insights and Analysis Lead

2010 - 2016
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.
Technologies: D3.js, RStudio Shiny, R, Tableau, Pentaho, Mondrian, PostgreSQL, Python

Mobile Analytics E-book and Reporting MVP

I was asked to help a mobile app developer add an analytics practice to their product offering; along with defining processes, implementing a pipeline to get data from their apps into the hands of their clients, and building external-facing dashboards. I wrote an e-book on mobile analytics that was also excerpted as a series of blog posts.
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.

Languages

SQL, Python, Bash, R

Tools

Apache Airflow, Tableau, Git, Jupyter, Jira, Mondrian, Sisense

Platforms

Linux, Amazon Web Services (AWS), Pentaho, Windows

Storage

PostgreSQL, MySQL, Database Architecture, PSQL

Other

Data Build Tool (dbt), Data Reporting, Data Analytics, Data Engineering, Data Warehousing, Data Warehouse Design, Data

Libraries/APIs

Pandas, Matplotlib, D3.js

Paradigms

ETL, Agile, Agile Product Management, Database Design

Frameworks

RStudio Shiny, Windows PowerShell

Collaboration That Works

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