Expert Kotlin Multiplatform engineer · Bordeaux, France
Hi, I’m Grégory.
I write the Kotlin that has to work everywhere.
As an Expert Engineer at SumUp, I build the point-of-sale app in Kotlin Multiplatform and own its most critical libraries: maths, order management and serialization. On my own time I write Kotlin tooling like k2pb, the KMP Protobuf library now running the POS serialization.
Latest articles
- Protobuf has no null: evolving a schema without breaking old messages
Adding a field, making it optional, making it required, removing it, adding a sealed subclass... each of these is a decision about bytes that were written months ago. How k2pb makes those decisions explicit.
- k2pb: Protobuf for Kotlin Multiplatform, without the surprises
Why I wrote my own Protobuf library when kotlinx.serialization already has one, and why it now runs the whole serialization layer of a point of sale.
- An audio visualization with Jetpack Compose
Yet another Jetpack Compose article, this time with a bit of Audio, to make your animations a bit more dynamic!
- Ktlint: a great 1st experience
Code generation is often perceived as a compile-time security. We're ready to pay it by increasing the build time. But what if a linter was a replacement for compile-time safety while delivering a better code.
- Should I use Jetpack ViewModel?
All new shiny libraries are not good for all projects, it has to responds to a real problem first. Let's see if you should pick Jetpack ViewModel.
Open source
k2pb
Kotlin Multiplatform Protobuf: generates .proto files and serializers from your @Serializable classes with KSP. Powers the whole serialization layer of the SumUp POS.
K2D
Kotlin to Documentation: generates Mermaid diagrams and Markdown tables straight from your code with KSP.
dokka-mermaid
Dokka plugin that renders Mermaid diagrams from your KDoc comments into your documentation.
GRIP
Gradle Replace In Place: a Gradle plugin keeping your documentation (or any file) up to date with a simple task.