New Relic's Elixir Agent

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The Open-Source Elixir Agent allows you to monitor your Elixir applications with New Relic. It helps you track transactions, distributed traces and other parts of your application's behavior and provides an overview of underlying BEAM activity.

View the Documentation

Support Statement

New Relic has open-sourced this project to enable monitoring of Elixir applications. This project is provided AS-IS WITHOUT WARRANTY OR SUPPORT, although you can report issues and contribute to the project here on GitHub.


We'd love to get your contributions to improve the elixir agent! Keep in mind when you submit your pull request, you'll need to sign the CLA via the click-through using CLA-Assistant. If you'd like to execute our corporate CLA, or if you have any questions, please drop us an email at


Install the Hex package


  • Erlang/OTP 22
  • Elixir 1.9
defp deps do
    {:new_relic_agent, "~> 1.0"}


You need to set a few required configuration keys so we can authenticate properly.

Via Application config

config :new_relic_agent,
  app_name: "My App",
  license_key: "license_key"

Via Environment variables

You can also configure these attributes via ENV vars, which helps keep secrets out of source code.


Telemetry-based Instrumentation

Some common Elixir packages are auto-instrumented via telemetry

Agent Features

There are a few agent features that can be enabled via configuration. Please see the documentation for more information.

Manual Instrumentation


The Plug and Phoenix instrumentation automatically report a Transaction for each request.

These Transactions will follow across any process spawned and linked (ex: Task.async), but will not follow a process that isn't linked (ex: Task.Supervisor.async_nolink).

To manually connect a Transaction to an unlinked process, you can use NewRelic.get_transaction and NewRelic.connect_to_transaction. See the docs for those functions for further details.

tx = NewRelic.get_transaction()

spawn(fn ->
  # ...

If you are using a Task to spawn work, you can use the pre-instrumented NewRelic.Instrumented.Task convienince module to make this easier. Just alias it in your module and all your Tasks will be instrumented. You may also use the functions directly.

alias NewRelic.Instrumented.Task

Task.Supervisor.async_nolink(MyTaskSupervisor, fn ->
  # This process wil be automatically connected to the Transaction...

Function Tracing

NewRelic.Tracer enables detailed Function tracing. Annotate a function and it'll show up as a span in Transaction Traces / Distributed Traces, and we'll collect aggregate stats about it. Install it by adding use NewRelic.Tracer to any module, and annotating any function with an @trace module attribute

defmodule MyModule do
  use NewRelic.Tracer

  @trace :work
  def work do
    # Will report as ``

Distributed Tracing

Requests to other services can be traced with the combination of an additional outgoing header and an :external tracer.

defmodule MyExternalService do
  use NewRelic.Tracer

  @trace {:request, category: :external}
  def request(method, url, headers) do
    NewRelic.set_span(:http, url: url, method: method, component: "HttpClient")
    headers = headers ++ NewRelic.distributed_trace_headers(:http)
    HttpClient.request(method, url, headers)

Pre-Instrumented Modules

NewRelic.Instrumented.Mix.Task To enable the Agent and record an Other Transaction during a Mix.Task, simply use NewRelic.Instrumented.Mix.Task. This will ensure the agent is properly started, records a Transaction, and is shut down.

defmodule Mix.Tasks.Example do
  use Mix.Task
  use NewRelic.Instrumented.Mix.Task

  def run(args) do
    # ...

NewRelic.Instrumented.HTTPoison Automatically wraps HTTP calls in a span, and adds an outbound header to track the request as part of a Distributed Trace.

alias NewRelic.Instrumented.HTTPoison

Other Transactions

You may start an "Other" Transaction for non-HTTP related work. This could used be while consuming from a message queue, for example.

To start an Other Transaction:

NewRelic.start_transaction(category, name)

And to stop the Transaction within the same process:



There are a few adapters which leverage this agent to provide library / framework specific instrumentation. Note that these will eventually be replaced with telemetry based instrumentation.


If you want to disable the agent, you can do it in two different ways:

  • Application config: config :new_relic_agent, license_key: nil
  • Environment variables: NEW_RELIC_HARVEST_ENABLED=false