Automatisch vs Windmill

The one question that decides this

Do you want a Zapier-shaped automation tool, or do you want a developer platform that happens to automate things? Automatisch describes itself bluntly as “The open source Zapier alternative,” and its GitHub description stays in that lane: “Build workflow automation without spending time and money.” Windmill is broader and more developer-coded: an “Open-source developer platform to turn scripts into workflows and UIs,” replacing not just Zapier but also Retool and Airplane. That is the real split: Automatisch is aiming at workflow automation as the product; Windmill is aiming at scripts, workflows, webhooks, and UIs as one programmable platform.

What each one is actually trying to be

Automatisch: Zapier, but open source

Automatisch is not being coy about the comparison. Its tagline is “The open source Zapier alternative,” which is refreshingly direct in a category full of tools pretending they invented connecting apps together. The GitHub description says: “The open source Zapier alternative. Build workflow automation without spending time and money.” That tells you the center of gravity: reduce Zapier dependency, keep the mental model familiar, and make automation feel like the product rather than a side effect of a bigger platform.

That focus is the best argument for Automatisch. If your team is trying to replace Zapier because pricing, vendor lock-in, or data residency is getting annoying, Automatisch is the cleaner read. It is not advertising itself as a generalized internal tools platform, a workflow engine benchmark flex, or a Retool replacement. It is basically saying: you came here for workflow automation; here is workflow automation. Sometimes the least galaxy-brained tool is the right one.

Windmill: scripts into workflows and UIs

Windmill is playing a much bigger game. Its tagline is “Open-source developer platform to turn scripts into workflows and UIs,” and the GitHub description goes even wider: “Open-source developer platform to power your entire infra and turn scripts into webhooks, workflows and UIs. Fastest workflow engine (13x vs Airflow). Open-source alternative to Retool and Temporal.” That is not a Zapier clone pitch. That is an infrastructure-adjacent pitch with automation as one slice of the surface area.

That makes Windmill more attractive if your automation work already lives near code. If the thing you want is “turn this script into a webhook,” “make this internal workflow reusable,” or “wrap this operational process in a UI,” Windmill’s positioning is pointed at you. It also means the product surface is probably broader than someone simply fleeing Zapier needs on day one. The upside is more power and more room to grow; the downside is that you are no longer shopping for a neat Zapier replacement, you are adopting a platform.

Head-to-head: the metrics

Automatisch’s GitHub repo, automatisch/automatisch, shows 13,932 stars, 1,057 forks, 288 open issues, license NOASSERTION, and a last push date of 2026-02-11. Windmill’s repo, windmill-labs/windmill, shows 17,549 stars, 1,068 forks, 808 open issues, license NOASSERTION, and a last push date of 2026-08-15. On the raw popularity scoreboard, Windmill has more stars. Forks are effectively close: 1,068 for Windmill versus 1,057 for Automatisch. On freshness, Windmill’s last push date is newer in the supplied data.

The open issue count is where you should avoid doing lazy numerology. Windmill has 808 open issues versus Automatisch’s 288, but that does not automatically mean Windmill is worse maintained. Bigger, broader projects tend to accumulate more issue volume because they have more surface area and more users trying weird things in production. Still, it is a signal worth noticing: if you are choosing Windmill, you are choosing a larger and noisier project footprint.

The license field for both is NOASSERTION, which is annoying but important to say plainly. That does not mean “no license,” and it does not mean “permissive,” “copyleft,” or “enterprise trap.” It means the provided data does not assert a license. If licensing matters to your company, and it should if you are self-hosting infrastructure that touches business workflows, you need to verify the repo directly before rolling either one into production. Do not let an alternatives directory do your legal homework for you.

What these metrics tell us: both projects are real enough to have meaningful GitHub gravity, Windmill has the larger star count, and both have similar fork counts. What they do not tell us: whether the connector you need works, whether upgrades are painless, whether the UI matches your team’s tolerance for complexity, or whether the official cloud is the right commercial escape hatch. Stars are a useful smoke test. They are not a procurement process.

Self-hosting

Automatisch supports both self-host and official-cloud, with a deploy difficulty of 2 out of 5. That fits its stated job: be an open-source Zapier alternative without turning every automation project into platform engineering cosplay. A 2/5 difficulty does not mean zero work, but it suggests the self-hosting path is meant to be approachable. The official SaaS price in the supplied data is $20/month, so there is also a hosted route if you want the shape of the product without owning the runtime.

Windmill also supports both self-host and official-cloud, with a deploy difficulty of 3 out of 5. That tracks with the broader scope: scripts, webhooks, workflows, UIs, and infrastructure-oriented use cases are naturally going to ask more of the operator. The official SaaS price in the supplied data is $10/month, which is lower than Automatisch’s supplied price, but the bigger distinction is not the first invoice. It is whether you want to run a workflow automation app or a developer platform that can become part of your internal tooling stack.

Community signals

Automatisch has 5 Hacker News mentions in the last 90 days in the supplied data. Its top HN item is “Show HN: Automatisch – Open source workflow automation, an alternative to Zapier,” posted by farukaydin on 2023-01-25, with 317 points and 58 comments. That is a solid launch-style signal: people understood the pitch because the pitch is obvious. “Open source Zapier alternative” is the sort of phrase that needs almost no onboarding, which is probably why it travels well.

Windmill has 0 Hacker News mentions in the last 90 days in the supplied data, but its top HN item is stronger historically: “Windmill: Open-source developer platform to turn scripts into workflows and UIs,” posted by InitEnabler on 2023-05-12, with 428 points and 109 comments. Again, that says something about the shape of interest. Windmill’s pitch is not just “Zapier but open source”; it is more of a developer platform pitch, and HN tends to perk up when a tool promises to turn scripts into operational systems without too much ceremony.

The Reddit data provided here is basically noise for this comparison. Automatisch’s top Reddit post in the supplied data is titled “"Reisen macht weltoffen" ist der bequemste Selbstbetrug der Mittelschicht” from r/Unbeliebtemeinung, and Windmill’s is “Windmill blade catching fire due to lightning strike” from r/Damnthatsinteresting. Neither appears to be about the software projects. So: cited, but not useful. This is exactly why “community sentiment” scraping often turns into pasteurized slop if nobody checks what the posts actually are.

What we'd do

Pick Automatisch if your main job is replacing Zapier with something recognizable, self-hostable, and narrower in scope. Pick Windmill if your automations are already developer-owned and you want scripts, workflows, webhooks, and UIs living in the same system. Automatisch wins on clarity of purpose; Windmill wins when “Zapier alternative” is too small a box for what you are actually building.