Zapier alternatives that are open source: licences and hosting compared
Which of these are actually open source by licence, what self-hosting really costs once your time is counted, and how to decide whether the source access buys you anything.
Aymeric Zhuo10 min read
On this page
"Open source" is doing two different jobs in most of these comparisons. Sometimes it means a permissive licence you can build a business on. Sometimes it means source-available with restrictions, which is a meaningfully different thing that people discover late.
This page is about that distinction, and about what self-hosting actually costs once somebody's time is counted. If what you want is simply not to pay, the free managed tiers are usually the better route and require no infrastructure at all.
Details were checked against each project's own pages in September 2026.
What we'll cover
Three reasons the source matters, and one that does not
Embedding it in a product you sell. If automation is going to be part of what your customers buy, the licence decides whether you may do that at all. This is the reason where the difference between licences is absolute rather than a matter of degree.
Keeping data on your own infrastructure. Self-hosted, nothing passing through your automations leaves machines you control. For regulated work this is sometimes the only arrangement that passes review, and no amount of vendor assurance substitutes.
Independence from a vendor's decisions. You can run the version you have indefinitely. A price rise, a discontinued feature, or an acquisition is not something that happens to you without warning.
And the reason that usually does not hold: cost. Open source is free of licence fees and not free to operate. Whether it is cheaper than a $9 managed plan depends entirely on whether the maintenance time is genuinely free to you, which it is only if someone already runs infrastructure as part of their job. This is the section most worth reading honestly, and it comes later.
If none of the first three applies to you, the source access is not buying you anything, and you should choose on capability and cost like any other purchase.
The licences, precisely
This is where the word gets slippery, and the difference is worth knowing before you build.
MIT is a conventional permissive open-source licence. Use it, modify it, redistribute it, sell products built on it, with essentially no obligation beyond preserving the notice. Activepieces is MIT at its core.
A sustainable-use licence permits internal use, modification, and self-hosting, while restricting selling the software as a hosted service to others. n8n uses this. It is source-available rather than open source under the standard definition, and for internal business automation the restriction is invisible.
AGPL requires that modifications be published if you offer the software over a network. Some projects in this space use it, and it is the licence corporate policies most often object to, so it is worth checking against your own rules.
The practical test: if you are automating your own processes, any of these is fine and the distinction is academic. If automation will be part of a product you sell, MIT is the safe choice and the others need reading carefully with someone who reads licences properly. Discovering this after six months of building is expensive.
n8n
The most established option and the one with the largest community.
Licence: sustainable-use. Internal use, modification and self-hosting permitted; selling it as a hosted service is not. Some enterprise features require a commercial licence.
Self-hosted: the community edition is free to run, with published container images and a large body of documentation and community material. It is the heavier of the mainstream options to operate, and queue mode for scaling adds genuine operational complexity.
Cloud, if you change your mind: Starter at £20 a month billed annually for 2,500 workflow executions, Pro at £50 for 10,000, with unlimited users, unlimited workflows and every integration on all plans. Billing is per execution regardless of complexity, so a forty-step workflow costs the same as a three-step one.
Suits: technical teams. Its node editor is visual with Code nodes taking JavaScript or Python, and data moves between nodes as structured items. Understanding that structure is what separates people who find n8n powerful from people who find it obstructive.
The strongest argument for it: community size. Whatever you hit, somebody has written about it, and that is worth more at two in the morning than any feature.
Activepieces
The permissively licensed option, and the lighter one to run.
Licence: MIT at the core, with some enterprise features held separately. This is the one to choose if you need to embed automation in something you sell.
Self-hosted: simpler to stand up and keep running than n8n, with a correspondingly smaller community when something breaks.
Cloud: Free at $0 for 100 credits a day with unlimited flows, Plus at $20 flat a month for three times that with no daily cap and up to five users, Team at $200 flat for five times Plus with 25 users and SSO, and a custom tier above. Overage runs around $0.007 a credit.
Suits: teams wanting something approachable, and AI-centred work particularly — its recent direction has been chat-based building, agents, and tables as first-class concepts.
The thing to check: the free cloud tier's 100 credits are per day and do not accumulate, so bursty workloads fail on their busy days. Self-hosting removes that constraint entirely, which is one of the better reasons here to actually self-host.
Windmill and the code-first end
Worth knowing about if your team writes code, because it answers a different question from the two above.
Windmill is an open-source platform for turning scripts into workflows and internal tools, supporting Python, TypeScript, Go and more. Rather than a visual builder with code as an escape hatch, it treats scripts as the primary unit and composes them into flows.
Suits: engineering teams who would rather write and version a script than arrange nodes on a canvas, and who want proper testing and review around their automations.
Does not suit: anyone hoping a non-developer will maintain it. That is the trade, and it is a clean one rather than a compromise.
What self-hosting actually costs
The licence is free. The operation is not, and this is where open-source automation projects most often disappoint.
The infrastructure is genuinely cheap: a modest VPS runs a few dollars a month, plus a database.
The time is the real number. Initial setup is a few hours. Ongoing you have updates to apply, backups to verify, monitoring to watch, certificates to renew, and a restoration to perform at some inconvenient moment. Call it one to two hours a month in a steady state, more when something breaks.
At a fully loaded engineering rate, two hours a month exceeds every managed plan discussed here. That is the arithmetic, and it does not change by wishing.
Self-hosting genuinely pays in three situations: high volume where per-execution pricing would be substantial, data residency requirements that rule out managed services, and organizations where someone already runs servers so the marginal cost of one more is close to zero.
It does not pay when the plan is that somebody will learn. The maintenance lands on top of their actual job, it is invisible until it fails, and those arrangements tend to end with a migration back to a managed plan about a year later, having cost more than the subscription would have.
Deciding
Choose MIT-licensed Activepieces if you will embed automation in a product you sell, or if your organization's policy requires a permissive licence.
Choose n8n if you want the largest community and the most mature self-hosted deployment, if your team is technical, or if your workflows are complex enough that per-execution pricing matters.
Choose Windmill if your team would rather write scripts than arrange nodes, and wants version control and testing around them.
Choose a managed plan if your reason for looking at open source was cost and nobody on the team already runs infrastructure. That is the most common case and the most commonly ignored.
Choose something else entirely if the real constraint is that the people who understand your processes cannot build automations in any of these. Every option here requires learning a builder and translating a process into it. On CodeWords you describe the process in plain language and Cody, the automation builder, builds it, connects it to your systems, and deploys it, with more than 3,000 integrations available. The free plan covers light use, with Pro at $39 per month and Business at $100 per month as usage grows; details are on the pricing page.
Frequently asked questions
Is n8n open source?
Not under the standard definition. Its sustainable-use licence permits internal use, modification and self-hosting, while restricting selling it as a hosted service. The term used for this is source-available. For internal automation it behaves exactly like open source; for building a product on top it does not.
Which is genuinely open source?
Activepieces is MIT at its core, which is a conventional permissive licence. Windmill is open source too. Check the specific licence on the specific components you need, since several projects hold enterprise features outside the open core.
Will self-hosting save me money?
At high volume with existing infrastructure capacity, substantially. At low volume without it, no — a few hours of engineering time a month costs more than any managed plan here. The honest test is whether somebody already runs servers as part of their job.
What do I need to self-host one of these?
A server, a database, container tooling, and a plan for updates, backups and monitoring. If those are familiar, an afternoon gets you running. If they are not, the managed plans are the recommendation rather than a compromise.
Can I self-host and move to cloud later, or the reverse?
With n8n and Activepieces, yes, since both offer managed versions of the same product, which makes the transition far easier than moving between vendors. Check how workflows transfer between your instance and theirs before relying on it.
Do open-source options have as many integrations?
n8n ships several hundred nodes and, more importantly, a generic HTTP node that reaches anything with an API, which makes catalog size less decisive than it appears. Activepieces has a smaller catalog with community contributions and the same HTTP fallback. Neither matches Zapier's breadth, and both cover the mainstream well.
What happens when I need to upgrade a self-hosted instance?
You do it, at a time you choose, having read the release notes and taken a backup. That control is the point, and it is also the obligation: an instance nobody updates accumulates security issues quietly, which is the failure mode of self-hosted automation rather than anything dramatic.
How much server does one of these need?
Less than people expect for modest use: a small VPS with a couple of gigabytes of memory handles a lot of business automation. What raises requirements is concurrency, long-running workflows, and anything processing large files. Start small and watch it, rather than provisioning for an imagined peak.
Who is responsible for security updates?
You are, entirely, and this is the obligation people underestimate. A self-hosted instance that nobody updates accumulates vulnerabilities silently, and because automation platforms hold credentials for every system they connect to, an unpatched one is a meaningful target. Subscribe to the project's release announcements and treat updates as routine maintenance.
Can I get commercial support for a self-hosted instance?
Both n8n and Activepieces offer commercial arrangements alongside their open versions, which is worth considering if you want the data residency of self-hosting with somebody to call. That combination is often the honest answer for regulated organizations, and it costs more than the managed cloud rather than less.
Does open source protect me from lock-in?
Less than people hope. No automation platform's workflows import into another's format, so moving between any two of these is a rebuild regardless of licence. What open source protects is your ability to keep running the version you have, indefinitely, on your own terms — which is genuine and is a different thing from portability.