# How Discord Added Distributed Tracing to Its Elixir Message-Passing Services

DevFeed: [How Discord Added Distributed Tracing to Its Elixir Message-Passing Services](<https://devfeed.tech/articles/why-the-f-ck-is-discord-still-using-elixir-18140.md>)

Original publisher: [Read original article](<https://hungrymindsdev.substack.com/p/why-the-fck-is-discord-still-using>)

Author: Alexandre Zajac

Published: 2026-05-18T15:39:51Z

Content type: article

Language: en

Sources: [Hungry Minds](<https://devfeed.tech/sources/hungry-minds.md>)

Topics: [Discord](<https://devfeed.tech/topics/discord.md>), [Elixir](<https://devfeed.tech/topics/elixir.md>), [tracing](<https://devfeed.tech/topics/tracing.md>), [Traces](<https://devfeed.tech/topics/traces.md>), [telemetry](<https://devfeed.tech/topics/telemetry.md>), [gRPC](<https://devfeed.tech/topics/grpc.md>)

Tags: [discord](<https://devfeed.tech/tags/discord.md>), [elixir](<https://devfeed.tech/tags/elixir.md>), [messages](<https://devfeed.tech/tags/messages.md>), [traces](<https://devfeed.tech/tags/traces.md>), [tracing](<https://devfeed.tech/tags/tracing.md>)

## AI overview

The article describes Discord's distributed-tracing implementation for Elixir services that communicate through message passing. It highlights trace-context propagation through message envelopes, a gradual zero-downtime migration, fanout-based sampling, lazy context unpacking, and restrictions on root spans after fanout.

## Source excerpt

PLUS: AI as Netflix model 📊, Spotify NLI via Claude 🎵, Subagent patterns 2026 🤖