# microsoft/FASTER

Fast persistent recoverable log and key-value store + cache, in C# and C++.

Repository: https://github.com/microsoft/FASTER
Canonical: https://ross.abutalabs.com/products/faster
Homepage: https://aka.ms/FASTER
Language: C#
License: MIT
License Family: permissive
Topics: key-value-store, hash-table, persistent, recoverable, concurrent, multi-threaded, library, logging, indexing
Last push: 2026-08-19T02:20:19+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-03T02:39:23.370411+00:00)
- activity 98, release rhythm 8, longevity 100
- inputs: {"age_days": 2953, "days_push": 15, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 6639, forks 596 (observed 2026-08-28T04:09:45.878497+00:00)

## What it is
FASTER is a high-performance concurrent persistent log and key-value store + cache library in C# and C++, supporting data larger than memory and fast non-blocking checkpointing. The repository is no longer actively maintained; Microsoft recommends its successor Garnet and the Tsavorite storage engine.

## Use cases
- embed a fast key-value store in a .NET application
- persist application state larger than memory with fast disk-backed storage
- build a write-heavy cache with point lookups and heavy updates
- add a recoverable commit log with low-latency commits
- implement consistent recovery via non-blocking checkpointing

## When to choose
- you need an embedded, in-process key-value store or log in C# or C++
- your workload is point lookups and heavy updates with data exceeding memory
- you want to trade performance for commit latency via checkpointing

## When to avoid
- you need a maintained project - use Garnet/Tsavorite instead
- you need a standalone networked cache server rather than an embedded library
- you need C++ support - only the C# version is actively documented

## Facets
- artifact type: library
- maturity: abandoned
- function: database, caching, logging, concurrency
- domain: databases, developer-tools, cloud-computing
- platform: cross-platform, cpp, dotnet
- tags: key-value-store, persistent-log, checkpointing, hash-index, embedded-database

## Member repositories
- microsoft/FASTER (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:45.878497+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 2026-08-29T17:43:12.208995+00:00, confidence not recorded.
  - readme: https://github.com/microsoft/FASTER (fetched 2026-08-28T04:09:45.878497+00:00, sha 864ea6e0ffe3)
- Data as of 2026-08-30T08:39:29.467469+00:00.