Yosys
Hacker ApprovedFPGA toolchain in Developer tools
Free open-source FPGA toolchain that is easy to get running on Lattice iCE40 and ECP5 chips, though critics say it lags Xilinx tools.
Free open-source FPGA toolchain that is easy to get running on Lattice iCE40 and ECP5 chips, though critics say it lags Xilinx tools.
17 people gave an opinion
- recommend it
- 14
- criticize it
- 3
- approval share
- 82%
Recommended in 9 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: not recommended
- May 2026: recommended
- June 2026: recommended
- July 2026: recommended
- August 2026: recommended
- September 2026: recommended
- October 2026: not recommended
- November 2026: not recommended (month in progress)
Why it carries the badge
- 14 people recommend itNeeds 10 or more, met.
- 4.7 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 9 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Open alternative to vendor tools
“I ended up using Yosys[1] as a toolchain for programing, instead of the one from the manufacturer”
Comment from 4 Dec 2025 in “Ask HN: How does one get involved in FPGA development?” “There already exist fantastic open source tools such as Yosys, Nextpnr, iverilog, OpenFPGALoader”
Comment from 23 Dec 2025 in “FPGAs Need a New Future” “these fantastic OSS tools exist and can provide a viable alternative to Big FPGA's tools”
Comment from 23 Dec 2025 in “FPGAs Need a New Future” Easy to get running
“Yosys is a super lightweight open-source FPGA toolchain that really easy to get up and running.”
Comment from 25 Aug 2026 in “SiFive's First Server Platform” “yosys & nextpnr support made things really damn easy when I was working with the ice40”
Comment from 17 Nov 2025 in “FPGA Based IBM-PC-XT” Works with iCE40 and ECP5
“I have used their ice40 and ECP5 FPGAs with Yosys for a couple of small projects and that worked perfectly fine.”
Comment from 24 May 2026 in “Why Is Vivado 2026.1 Dropping Linux Support for Free Tier?” “yosys & nextpnr support made things really damn easy when I was working with the ice40”
Comment from 17 Nov 2025 in “FPGA Based IBM-PC-XT” Decent for hobby projects
“I have used their ice40 and ECP5 FPGAs with Yosys for a couple of small projects and that worked perfectly fine.”
Comment from 24 May 2026 in “Why Is Vivado 2026.1 Dropping Linux Support for Free Tier?” “Decent support from Yosys for hobby stuff at least.”
Comment from 22 Dec 2025 in “Pure Silicon Demo Coding: No CPU, No Memory, Just 4k Gates”
What people recommend instead
The same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| YosysThis page | 14 | 3 | 82% | 9 | — | Approved |
| Vivado Design Suite | 13 | 88 | 13% | 5 | — | — |
What people said
16 of the 19 comments that mention it, newest first. Each links to the original comment.
“turned out to be some kind of problem in the yosys synthesis tool”
“Yosys is a super lightweight open-source FPGA toolchain that really easy to get up and running.”
“Approximately nobody uses Yosys.”
“Yosys is still years behind Xilinx”
“it is supported by the Yosys open source toolchain”
“non-trivial to integrate with the vivado backend and doesn't bring many benefits”
“Sounds like yosys is good.”
“I have used their ice40 and ECP5 FPGAs with Yosys for a couple of small projects and that worked perfectly fine.”
“I'm using Yosis for my Ice40 Lattice FPGA purely because their Linux support is bad.”
“there are quite a bit of opportunities to learn stuff”
“way too big to be running in a small app in the browser”
“these fantastic OSS tools exist and can provide a viable alternative to Big FPGA's tools”
“There already exist fantastic open source tools such as Yosys, Nextpnr, iverilog, OpenFPGALoader”
“Decent support from Yosys for hobby stuff at least.”
“I ended up using Yosys[1] as a toolchain for programing, instead of the one from the manufacturer”
“yosys & nextpnr support made things really damn easy when I was working with the ice40”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.