Projects & Open Source
An organized index of open source work, separated into core OpenTelemetry leadership, personal open source repositories, and Scala ecosystem projects and books.
OpenTelemetry
I'm a maintainer of OpenTelemetry. My primary focus and contributions center on the project's wire protocols, specification, and instrumentation (where I focus on schema tooling and semantic conventions):
| Project | Focus & Contributions | Repository |
|---|---|---|
| OpenTelemetry Weaver | Semantic conventions schema engine, multi-language code generation, and live telemetry policy verification written in Rust. | open-telemetry/weaver |
| OpenTelemetry Specification | Core cross-language specification defining tracing, metrics, logging, baggage, and SDK architecture requirements. | open-telemetry/opentelemetry-specification |
| OpenTelemetry Protocol (OTLP) | Specification and protobuf definitions for the vendor-neutral wire protocol used to transmit telemetry. | open-telemetry/opentelemetry-proto |
| Semantic Conventions | Standardized naming conventions, attribute definitions, and schema models across cloud-native infrastructure and applications. | open-telemetry/semantic-conventions |
Personal Open Source Projects
Personal repositories and experiments from github.com/jsuereth, ordered reverse chronologically by creation date.
These projects all represent some interesting thought experiment or viable path forward for real systems. Some, e.g. sauerkraut and shady-side, were used for feedback to the Scala 3 Language specification. Others, e.g. otlp-mmap, are prototypes that I hope will lead to more optimal instrumentation in OpenTelemetry.
| Project | Status | Created | Description | Repository |
|---|---|---|---|---|
| o11y-by-design | Active | 2025 | Live reference application demonstrating schema-driven telemetry with Weaver (KubeCon). | jsuereth/o11y-by-design |
| otlp-mmap | Active | 2024 | Experimental high-throughput zero-copy memory-mapped file storage for OTLP in Rust. | jsuereth/otlp-mmap |
| ottl-proposal | Past Project | 2024 | A proposal for OpenTelemetry Transformation Language (OTTL) improvements along with a prototype implementation in Rust. | jsuereth/ottl-proposal |
| sauerkraut | Past Project | 2020 | Reimagined compile-time serialization and pickling exploring Scala 3 macro capabilities. | jsuereth/sauerkraut |
| shady-side | Past Project | 2019 | Prototype Scala-to-GLSL shader translation pipeline with test scaffolding. | jsuereth/shady-side |
| raspberry-potter | Past Project | 2016 | Harry Potter wand motion detection via Raspberry Pi 3 and IR camera for home automation. | jsuereth/raspberry-potter |
| nerdcapture | Past Project | 2013 | Screen and audio capture utility built using Play Iteratees. | jsuereth/nerdcapture |
Scala Projects & Published Book Example Repositories
Prior to focusing on observability and systems in Rust, I spent a decade working extensively in the Scala ecosystem on build systems, compiler bridges, and language ergonomics.
Published Books
| Title | Publisher / Year | Description | Links |
|---|---|---|---|
| Scala in Depth | Manning Publications (2012) | A comprehensive guide to language internals, implicit mechanics, and functional design on the JVM. | Manning • Code |
| sbt in Action | Manning Publications (2015) | Co-authored with Matthew Farwell. The definitive manual on build automation and dependency graphs with sbt. | Manning • Code |
Tooling & Libraries
| Project | Status | Created | Description | Repository |
|---|---|---|---|---|
| visualz | Past Project | 2017 | Dorking around with various computational and procedural visual generation in Scala. | jsuereth/visualz |
| cat | Past Project | 2015 | Essence of the Iterator Pattern code, used during "Introduction to category theory" talk. | jsuereth/cat |
| streamerz | Past Project | 2015 | Playground of Akka Streams and video processing in Scala. | jsuereth/streamerz |
| snark | Past Project | 2015 | Twitter command line client example for NE Scala 2015. | jsuereth/snark |
| viewducers | Past Project | 2014 | Exploring Clojure-style Transducers within Scala collection views. | jsuereth/viewducers |
| binary-resilience | Past Project | 2012 | Source code proofs and techniques for maintaining binary compatibility on the JVM. | jsuereth/binary-resilience |
| scala-cel | Past Project | 2011 | Scala Community Extension Libraries. | jsuereth/scala-cel |
| scala-arm | Past Project | 2009 | Automatic Resource Management (ARM) library for Scala. | jsuereth/scala-arm |
| scala-mojo-support | Past Project | 2009 | Helper toolkit for creating Maven Mojo plugins in Scala. | jsuereth/scala-mojo-support |
| sbt (Simple Build Tool) | Past Work | — | Former lead maintainer. Co-architected sbt's client-server model, task engine, and Zinc compiler bridge. | sbt/sbt |
Joke Projects
Here's a set of random thought experiments or educational projects I shared with the world. Some have interesting lessons in them, e.g. lambda-doge is where I finally created a "real" system with type inference and compilation from scratch, and got a handle on the architectural significance of different compiler designs.
| Project | Status | Created | Description | Repository |
|---|---|---|---|---|
| lambda-doge | Past Project | 2014 | An esoteric, educational language that takes itself seriously. | jsuereth/lambda-doge |
| evil_monkey | Past Project | 2014 | Using Scala 2's Dynamic for fun and profit. | jsuereth/evil_monkey |
| protocopter | Past Project | 2008 | An evolution from lolcode that never did anything. | jsuereth/protocopter |