Harry Percival

Harry Percival

Python and TDD enthusiast

  • @hjwp

London, United Kingdom

Areas of Expertise:

  • Python
  • TDD
  • consulting
  • speaking
  • programming
  • training
  • writing
After an idyllic childhood spent playing with BASIC on French 8-bit computers like the Thomson T-07 whose keys go "boop" when you press them, Harry spent a few years being deeply unhappy as a management consultant. Soon he rediscovered his true geek nature, and was lucky enough to fall in with a bunch of XP fanatics, working on the pioneering but sadly defunct Resolver One spreadsheet. He now works at PythonAnywhere LLP, and spreads the gospel of TDD world-wide at talks, workshops and conferences, with all the passion and enthusiasm of a recent convert.

Test-Driven Development with Python Test-Driven Development with Python
by Harry Percival
June 2014
Print: $44.99
Ebook: $35.99

Test-Driven Development Test-Driven Development
by Harry Percival
October 2014
Video: $59.99

Harry blogs at:

Signals from the 2015 O’Reilly Velocity Conference in Santa Clara

May 29 2015

People from across the Web operations and performance worlds are coming together this week for the 2015 O’Reilly Velocity Conference in Santa Clara. Below, we’ve assembled notable keynotes, interviews, and insights from the event. Think like a villain Laura Bell … read more

Designers as data scientists

May 29 2015

Download a free copy of “The New Design Fundamentals” ebook, a curated collection of chapters from our Design library. Note: this post is an excerpt from “Designing with Data,” by Rochelle King and Elizabeth F. Churchill, which is included in … read more

Signals from the 2015 O’Reilly Velocity Conference in Santa Clara

May 29 2015

People from across the Web operations and performance worlds are coming together this week for the 2015 O’Reilly Velocity Conference in Santa Clara. Below, we’ve assembled notable keynotes, interviews, and insights from the event. Think like a villain Laura Bell … read more

Designers as data scientists

May 29 2015

Download a free copy of “The New Design Fundamentals” ebook, a curated collection of chapters from our Design library. Note: this post is an excerpt from “Designing with Data,” by Rochelle King and Elizabeth F. Churchill, which is included in … read more

Ask the Readers: What expense do you most want to dump?

May 29 2015

This article is by editor Linda Vergon. Is there a bill you pay that you absolutely detest? Occasionally, I’ll get an attitude about paying one bill or another. (Ha! Paying taxes on April 15 is one bill that comes to mind immediately, for example.) I recognize that there is a… read more

9.3 trillion reasons fintech could change the developing world

May 29 2015

Request an invitation to Next:Money, O’Reilly’s conference focused on the fundamental transformation taking place in the finance industry. A relatively commonplace occurrence — credit card fraud — made me reconsider the long-term impact of financial technology outside the Western world. … read more

9.3 trillion reasons fintech could change the developing world

May 29 2015

Request an invitation to Next:Money, O’Reilly’s conference focused on the fundamental transformation taking place in the finance industry. A relatively commonplace occurrence — credit card fraud — made me reconsider the long-term impact of financial technology outside the Western world. … read more

Four short links: 29 May 2015

May 29 2015

Using Logs to Build Solid Data Infrastructure — (Martin Kleppmann) — For lack of a better term I’m going to call this the problem of “data integration”. With that I really just mean “making sure that the data ends up … read more

Four short links: 29 May 2015

May 29 2015

Using Logs to Build Solid Data Infrastructure — (Martin Kleppmann) — For lack of a better term I’m going to call this the problem of “data integration”. With that I really just mean “making sure that the data ends up … read more

Applied DevOps and the potential of Docker

May 28 2015

Editor’s note: this post is from Karl Matthias and Sean P. Kane, authors of “Docker Up & Running,” a guide to quickly learn how to use Docker to create packaged images for easy management, testing, and deployment of software. At … read more

Webcast: Outside-in TDD and Unit Test Isolation with Python, Django and Selenium
June 05, 2014
This webcast will explore the methodology of outside-in test-driven development (TDD), as applied to a web application.

Webcast: TDD Web Development from Scratch
June 26, 2013
In this hands-on webcast presented by Harry Percival author of Test-Driven Development with Python, you will learn: how to use TDD to build a web application from the ground up, full functional testing using the Selenium browser automation tool, and ...