# facebookincubator/velox

A composable and fully extensible C++ execution engine library for data management systems.

Repository: https://github.com/facebookincubator/velox
Canonical: https://ross.abutalabs.com/products/velox
Homepage: https://velox-lib.io/
Language: C++
License: Apache-2.0
License Family: permissive
Topics: data-management, query-processing
Last push: 2026-08-26T22:29:33+00:00

## Health v2 (maintenance only)
Score: 77/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 35, longevity 100
- inputs: {"age_days": 1867, "days_push": 7, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4201, forks 1592 (observed 2026-08-28T04:08:38.928553+00:00)

## What it is
Velox is a composable, extensible C++ execution engine library for data management systems, created by Meta. It provides reusable vectorized components—types, columnar vectors, expression evaluation, functions, operators, and I/O connectors—that developers use to build analytical query engines for batch, interactive, streaming, and AI/ML workloads.

## Use cases
- build a custom analytical query engine in C++
- accelerate Apache Spark with native execution via Apache Gluten
- execute optimized query plans with vectorized operators
- read and process Parquet, ORC, and Nimble files from S3, HDFS, or GCS
- implement Presto or Spark compatible function semantics
- debug and replay query plan fragments in isolation
- build stream processing or AI/ML data pipelines on a shared execution engine

## When to choose
- you are building or optimizing a compute engine and need high-performance vectorized execution primitives
- you want Arrow-compatible columnar processing with encodings like dictionary and RLE
- you need consistent Presto/Spark function semantics across multiple engines
- you want to offload Spark or Presto execution to a native C++ runtime

## When to avoid
- you need an end-to-end SQL query engine with a parser and optimizer—Velox provides neither
- you are an end user looking for a ready-to-run database or analytics tool
- your project is not C++ or lacks integration effort budget for a low-level library

## Facets
- artifact type: library
- maturity: active
- function: database, serialization, data-science, etl, streaming
- domain: databases, big-data, analytics
- platform: cpp, cross-platform
- tags: query-execution, columnar, arrow-compatible, vectorized-execution, query-engine, presto, spark, data-engineering, linux, macos

## Member repositories
- facebookincubator/velox (main) score 77

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:38.928553+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 2026-08-29T18:22:32.602378+00:00, confidence not recorded.
  - readme: https://github.com/facebookincubator/velox (fetched 2026-08-28T04:08:38.928553+00:00, sha 0bfb679552b7)
  - homepage: https://velox-lib.io/ (fetched 2026-08-29T09:12:51.020497+00:00, sha ee74f7653cae)
  - site_page: https://velox-lib.io/docs/community (fetched 2026-08-29T09:12:51.029890+00:00, sha fef650d6ac15)
  - site_page: https://velox-lib.io/blog/velox-query-tracing (fetched 2026-08-29T09:12:51.061804+00:00, sha 5c5d1f5d8961)
- Data as of 2026-08-30T08:39:29.467469+00:00.