Overthinking CSV With Cesil: An Introduction

Several months ago About a year ago (how time flies) I decided to spin up a new personal project to get familiar with all the new goodies in C# 8 and .NET Core 3. I happened to be dealing with some frustrating CSV issues at the time, so the project was a CSV library.

Once I got into the meat of the project, I started really overthinking things. The end result was Cesil – a pre-release package is available on Nuget, source is on GitHub, and it’s got reference documentation and a prose wiki. It’s released under the MIT license.

When I say I was overthinking things, I mean that rather than build a toy just for my own edification I ended up trying to do The Right Thing™ for a .NET library released in 2020. This, at least 14 part, blog series will cover exactly what that entailed but in short I committed to:

• Async as a first class citizen
• Maximum consumer flexibility
• Extensive documentation
• Comprehensive test coverage
• Adopting C# 8 features
• Modern patterns and conventions
• Efficiency, especially in terms of allocations

Interpretations of each of those points can be a matter of opinion, and I’m not going to claim to have 100% correct opinions. I attempted to record both things I consider opinions and open questions, both of which I’ll expound upon as this series continues.

My hope is that Cesil is easy to use, hard to misuse, handles the common cases out of the box, and can be configured to handle almost anything you might want to do with CSV. I intend to respond to feedback and make changes as needed over the course of this series to make it more likely those hopes are realized.

A final bit of overthinking on the whole project has been around sustainable open source. There’s been a fair amount of discussion on the subject, the gist of which is that loads of people and companies benefit from volunteers doing skilled work without compensation – and that is an unsustainable practice. As a small experiment inline with these thoughts, I’ve set up GitHub Sponsors for Cesil with a few low commitment tiers. I’ll both be using the tiers to prioritize responding to some feedback, and reporting on the results of this experiment towards the end of the blog series.

Now with the introduction out of the way, I’m ready to dive into technical bits in the next post…