# Yosys

Hacker Approved page: https://hackerapproved.com/p/yosys/

11 people recommended Yosys in Hacker News comments, 3 had mixed feelings and 3 criticized it, November 2025 to October 2026. It was recommended in 8 of 12 months, in 11 threads. It meets the Hacker Approved badge rule.

**Verdict:** Free open-source FPGA toolchain that is easy to get running on Lattice iCE40 and ECP5 chips, though critics say it lags Xilinx tools.

Summary written by Claude from 16 comments.

## Why people recommend it

- Open alternative to vendor tools (3 comments in the sample): "I ended up using Yosys[1] as a toolchain for programing, instead of the one from the manufacturer" ([source](https://news.ycombinator.com/item?id=46152518)) "There already exist fantastic open source tools such as Yosys, Nextpnr, iverilog, OpenFPGALoader" ([source](https://news.ycombinator.com/item?id=46361328)) "these fantastic OSS tools exist and can provide a viable alternative to Big FPGA's tools" ([source](https://news.ycombinator.com/item?id=46366231))
- Easy to get running (2 comments in the sample): "Yosys is a super lightweight open-source FPGA toolchain that really easy to get up and running." ([source](https://news.ycombinator.com/item?id=49439575)) "yosys & nextpnr support made things really damn easy when I was working with the ice40" ([source](https://news.ycombinator.com/item?id=45950208))
- Works with iCE40 and ECP5 (1 comment in the sample): "I have used their ice40 and ECP5 FPGAs with Yosys for a couple of small projects and that worked perfectly fine." ([source](https://news.ycombinator.com/item?id=48258710))
- Decent for hobby projects (1 comment in the sample): "Decent support from Yosys for hobby stuff at least." ([source](https://news.ycombinator.com/item?id=46353200))

## The badge

A product earns the Hacker Approved badge when at least 10 people recommend it, recommenders outnumber critics at least 2 to 1 (mixed feelings count toward neither side), it was recommended in at least 4 of the 12 months and in at least 5 different threads, and no single thread supplies more than half of the people who recommend it. Health and money products are never badged.

## Cite as

Hacker Approved, "Yosys", https://hackerapproved.com/p/yosys/ (11 recommend, 3 mixed, 3 criticize; Hacker News comments, November 2025 to October 2026).

Counts updated 2 Nov 2026, with data through October 31, 2026.