Meetup #2: Qt C++ APIs on Android / Providing a Library: the Rarely Spoken Parts

Please join us for our second official C++ Helsinki Meetup! We will be meeting at the Maria01 Event Space for a series of talks and discussion about the C++ programming language.

This meetup is sponsored by Qt Group. We will meet at the Event Space at Maria01, Lapinlahdenkatu 16, 00180 Helsinki, on Tuesday 5 September 2023 at 18:00. Anyone interested in the C++ programming language is welcome to attend! Note however that the room has space for 80 people maximum, so attendance is limited to 80 guests. Please RSVP if you plan to attend, and please cancel your RSVP again if you find out later that you cannot attend so that someone else can use your slot.

The content for this meetup includes:

Assam Boudjelthia: How Qt C++ APIs work on Android

The presentation will talk about Qt under Android, how Qt for Android works and how its APIs co-work with the Android APIs.

Assam Boudjelthia is a Senior Software Engineer working at Qt Group for close to 5 years, and has been programming in C++ since his bachelor degree around 2013. He has been working on Qt for Android offering including both the APIs and tooling, for the goal of making Qt more mobile friendly.

Jussi Pakkanen: Providing a Library: the Rarely Spoken Parts

There is more to providing a library than shipping a header and a prebuilt binary. In order to obtain and keep users a library has to handle a lot of conflicting requirements like usability, functionality, backwards compatibility (both of the API and ABI kind), embeddability into scripting languages, suitability for inclusion into Linux distributions and so on. There is not that much information available about these requirements and most people find them out by trial and error.

In this talk we examine the brand new open source library CapyPDF (github.com/jpakkane/capypdf) for generating PDFs that has been designed with two main goals in mind. First of all the library only uses C++23 (or newer) in its implementation but it has to provide an external API that is maximally usable from pretty much any language or framework. We'll examine how to expose functionality in a way that is both exhaustive and usable. We'll also see how the external API causes design changes inside the library even though in theory the implementation should be fully hidden from the outside. Finally we'll look at how to provide a Python extension library via PyPI, including the library's dependencies, as a prebuilt Python wheel.

Jussi Pakkanen is the original creator and current project lead of the Meson build system. He has worked on most layers of the modern computing landscape ranging from kernel and low level libraries to web services, security work and computer games. In his spare time he can be found playing games, watching bad movies and writing books, one which has just been published.