November 2022 Meeting

The November 2022 meeting of LRUG will be on Monday the 14th of November, from 6:00pm to 8:00pm (meeting starts at 6:30pm).

👪 in person meeting alert 👪

In-person seems to be working out, so we're doing it again. This time the lovely folks at Zappi are hosting us in their offices, on Camden High St. Full venue and registration details are given below.


Data Indexing with RGB (Ruby, Graphs and Bitmaps)

Benji Lewis (also here) says:

In this talk, we will go on a journey through Zappi’s data history and how we are using Ruby, a graph database, and a bitmap store to build a unique data engine. A journey that starts with the problem of a disconnected data set and serialised data frames, and ends with the solution of an in-memory index.

We will explore how we used RedisGraph to model the relationships in our data, connecting semantically equal nodes. Then delve into how a query layer was used to index a bitmap store and, in turn, led to us being able to interrogate our entire dataset orders of magnitude faster than before.

  1. LRUG November 2022 - Benji Lewis - Data indexing with RGB (Ruby, Graphs and Bitmaps)

ruby/debug - The best investment for your productivity

Stan Lo says:

In this talk, I will demonstrate 3 powerful debugging techniques using Ruby's new debugger ruby/debug:

  • Step-debugging
  • Frame navigation
  • Breakpoint commands

By using them together, we can reduce unnecessary context switching and make our debugging sessions more efficient. You will also learn more about ruby/debug while we walk through these techniques with its commands and console.

And finally, I will show you how to level up our productivity even further by automating debugging steps using ruby/debug's scriptable breakpoints.

  1. LRUG November 2022 - Stan Lo - ruby/debug - The best investment for your productivity
  2. ruby/debug - The best investment for your productivity

Keeping developers happy with a fast CI

Christian Bruckmayer says:

When talking about performance, most developers think application speed, faster algorithms or better data structures. But what about your test suite? CI time is developer waiting time!

At Shopify we have more than 170,000 Ruby tests and we add 30,000 more annually. The sheer amount of tests and their growth requires some aggressive methods. We will illustrate some of our techniques including monitoring, test selection, timeouts and the 80/20 rule. If you have experience in writing tests and want to learn tricks on how to speed up your test suite, this talk is for you!

  1. LRUG November 2022 - Christian Bruckmayer - Keeping developers happy with a fast CI
  2. Slides from the Rubyconf 2021 version of 'Keeping developers happy with a fast CI'


When the talks come to an end we'll decamp to a local pub for some food, some drinks and some chat with your fellow attendees.

Of course, even though this is the socialising part and seems more informal, please remember that still we consider it to be a part of the meeting and covered by our code of conduct.

Venue & Registration

Prior to attending you should familiarise yourself with our README paying close attention to the code of conduct which applies to all attendees.

Secure your place

Hopefully you all remember that physical meetings involve finite space and so to be guaranteed entry you need to register via eventbrite.


The address of the venue:

Theatre House
97 - 99 Camden High St

See on a map

The venue has a hard limit of 100 people. If you register and realise you can't come, please use eventbrite to give up your place so we can someone else come in your place. We might be able to let in people on the night who haven't registered, but we can't guarantee it.

Posted by Alessandro Proserpio on Oct 20, 2022