# ghdl/ghdl

VHDL 2008/93/87 simulator

Repository: https://github.com/ghdl/ghdl
Canonical: https://ross.abutalabs.com/products/ghdl
Language: VHDL
License: GPL-2.0
License Family: copyleft
Topics: vhdl, ghdl, simulator, testbench, compiler, gcc, llvm, hardware, hacktoberfest
Last push: 2026-08-26T18:59:32+00:00

## Health v2 (maintenance only)
Score: 82/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 50, longevity 100
- inputs: {"age_days": 3941, "days_push": 7, "days_rel": 179, "gap_med": 108, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 2868, forks 425 (observed 2026-08-28T04:07:26.917374+00:00)

## What it is
GHDL is an open-source analyzer, compiler, simulator, and experimental synthesizer for the VHDL hardware description language, supporting IEEE 1076 standards from 1987 through 2008. It compiles VHDL designs to native machine code for high-speed simulation rather than interpreting them.

## Use cases
- simulate VHDL designs
- run VHDL testbenches
- compile VHDL 2008 code
- verify FPGA RTL before synthesis
- simulate digital hardware on a PC
- check VHDL code for standards compliance
- integrate VHDL simulation into CI pipelines

## When to choose
- you need a free, open-source VHDL simulator
- you want fast native-code simulation of VHDL designs
- you need support for multiple VHDL standard versions (87/93/02/08)
- you want to script VHDL testbenches in CI without commercial EDA licenses

## When to avoid
- you need Verilog or SystemVerilog simulation
- you require vendor-verified synthesis for production FPGA flows
- you need advanced commercial simulator features like coverage-driven verification or UVM support

## Facets
- artifact type: application
- maturity: active
- function: compiler, interpreter, testing, developer-tools
- domain: hardware, simulation, developer-tools, testing
- platform: windows, cross-platform, cli
- tags: vhdl, hdl-simulator, testbench, llvm, gcc, hardware-description-language, synthesizer, linux, macos

## Member repositories
- ghdl/ghdl (main) score 82

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:07:26.917374+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 2026-08-30T07:35:55.865212+00:00, confidence not recorded.
  - readme: https://github.com/ghdl/ghdl (fetched 2026-08-28T04:07:26.917374+00:00, sha 2af30a44ef44)
- Data as of 2026-08-30T08:39:29.467469+00:00.