# dotnet/coreclr

CoreCLR is the runtime for .NET Core. It includes the garbage collector, JIT compiler, primitive data types and low-level classes.

Repository: https://github.com/dotnet/coreclr
Canonical: https://ross.abutalabs.com/products/coreclr
Homepage: https://docs.microsoft.com/dotnet/core/
License Family: other
Topics: coreclr, corefx, c-sharp, dotnet, dotnet-core, dotnetcore, runtime, jit
Archived: true
Last push: 2023-01-21T00:33:11+00:00

## Health v2 (maintenance only)
Score: 10/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4233, "days_push": 1321, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: archived, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 12766, forks 2588 (observed 2026-08-28T04:10:59.733445+00:00)

## What it is
CoreCLR is the execution runtime for .NET Core, containing the garbage collector, JIT compiler, primitive data types, and low-level base classes. The repository has been consolidated into dotnet/runtime and is no longer actively developed here.

## Use cases
- run and execute .NET Core applications
- understand how the .NET garbage collector works
- contribute to or study the .NET JIT compiler
- debug low-level runtime issues in .NET Core apps
- build a custom .NET runtime from source

## When to choose
- you need the historical CoreCLR source for research or archaeology
- you are studying runtime internals, GC, or JIT design
- you maintain a fork or legacy .NET Core 1.x/2.x build

## When to avoid
- you want to develop or contribute to the current .NET runtime - use dotnet/runtime instead
- you just need to run .NET apps - install the official .NET SDK/runtime
- you need a supported, up-to-date runtime with security fixes

## Facets
- artifact type: library
- maturity: abandoned
- function: compiler, interpreter
- domain: programming-languages, developer-tools, performance
- platform: cross-platform, windows
- tags: dotnet, coreclr, jit, garbage-collector, runtime, c-sharp, archived-repo, linux, macos

## Member repositories
- dotnet/coreclr (main) score 10

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:10:59.733445+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 2026-08-29T17:13:48.690520+00:00, confidence not recorded.
  - readme: https://github.com/dotnet/coreclr (fetched 2026-08-28T04:10:59.733445+00:00, sha c10ab44da93a)
  - homepage: https://docs.microsoft.com/dotnet/core/ (fetched 2026-08-29T08:10:22.527057+00:00, sha 03a7165c9941)
  - site_page: https://learn.microsoft.com/en-us/dotnet/core/install/windows (fetched 2026-08-29T08:10:22.532698+00:00, sha 2257f52720dc)
  - site_page: https://learn.microsoft.com/en-us/dotnet/core/install/linux-ubuntu (fetched 2026-08-29T08:10:22.535500+00:00, sha be803210fe7e)
  - site_page: https://learn.microsoft.com/en-us/dotnet/core/install/how-to-detect-installed-versions (fetched 2026-08-29T08:10:22.537855+00:00, sha 6ba301148f7b)
  - site_page: https://learn.microsoft.com/en-us/lifecycle/faq/internet-explorer-microsoft-edge (fetched 2026-08-29T08:10:22.530020+00:00, sha c363b2f43d4b)
- Data as of 2026-08-30T08:39:29.467469+00:00.