# xoofx/ultra

An advanced profiler for .NET Applications on Windows and macOS

Repository: https://github.com/xoofx/ultra
Canonical: https://ross.abutalabs.com/products/xoofx-ultra
Language: C#
License: BSD-2-Clause
License Family: permissive
Topics: dotnet, etw, profiler
Last push: 2026-07-28T13:02:10+00:00

## Health v2 (maintenance only)
Score: 85/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 94, release rhythm 95, longevity 46
- inputs: {"age_days": 653, "days_push": 36, "days_rel": 36, "gap_med": 1.0, "n_releases_24m": 15}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1186, forks 23 (observed 2026-08-28T04:03:55.084640+00:00)

## What it is
Ultra is an advanced sampling profiler for .NET applications on Windows (ETW-based) and macOS Apple Silicon (EventPipe-based). It produces lightweight traces viewable in the Firefox Profiler UI with timeline, flamegraph, call tree, and GC/JIT event visualizations.

## Use cases
- profile a .NET application's CPU usage
- find performance bottlenecks in dotnet code
- generate flamegraphs for .NET apps
- analyze GC allocation and JIT compile events
- capture native and managed call stacks on Windows
- profile a running .NET process by PID

## When to choose
- you need a lightweight sampling profiler for .NET on Windows or macOS ARM64
- you want Firefox Profiler-compatible traces that are shareable online
- you need kernel, native, and managed stack traces in one tool

## When to avoid
- you need a profiler for non-.NET languages
- you cannot run from an elevated prompt on Windows
- you need memory heap snapshots or allocation tracking beyond GC events

## Facets
- artifact type: cli-tool
- maturity: active
- function: monitoring, benchmarking, developer-tools
- domain: developer-tools, performance
- platform: windows, cli, dotnet
- tags: profiler, sampling-profiler, etw, eventpipe, flamegraph, dotnet, performance-analysis, command-line, macos

## Member repositories
- xoofx/ultra (main) score 85

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:55.084640+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T06:24:05.934064+00:00, confidence not recorded.
  - readme: https://github.com/xoofx/ultra (fetched 2026-08-28T04:03:55.084640+00:00, sha 327f8d3f9015)
- Data as of 2026-08-30T08:39:29.467469+00:00.