Sim and Hubzoid both help teams build AI agents and workflows and run them on their own infrastructure. Sim (opens in a new tab) is a visual workspace with a canvas, a knowledge base and many integrations. Hubzoid is an open-source platform for internal AI agents: your team's knowledge, rules and tools as files in one Hub, used in chat, workflows and the assistants people already use.
In short. Choose Hubzoid when you want your agent's knowledge and rules as files you can review and keep in Git, with per-person access, approvals and audit in the open-source product. Choose Sim when people who prefer not to code should build workflows visually from ready integrations.
Hubzoid and Sim at a glance
✓ yes · ◐ partly, or paid · ✗ no · ○ not documented
| Hubzoid | Sim | |
|---|---|---|
| Team controls in the open-source product | ✓ Apache 2.0, all of it | ◐ SSO, permission groups and audit logs need an enterprise subscription in production |
| Per-person tool permissions | ✓ Checked in code before a tool runs | ◐ Permission groups are an enterprise feature |
| Knowledge and rules as reviewable files in Git | ✓ | ◐ Workspace knowledge base |
| Self-hosted without a vendor service | ✓ | ◐ Chat uses a key from Sim's service |
| Use your Claude Code login instead of an API key | ✓ On your laptop | ○ |
| Visual builder for non-coders | ◐ A coding assistant writes the files | ✓ |
| Ready integrations | ◐ MCP connectors and Python tools | ✓ A large library |
| Approval before an action | ✓ | ✓ |
| Slack | ✓ | ✓ |
| MCP server for your assistant | ✓ | ✓ |
| Traces, usage and cost | ✓ | ✓ |
| Price | Free, Apache 2.0 | Free core. Per-user cloud plans. Enterprise subscription for team controls |
Sources: Sim's repository (opens in a new tab), enterprise license (opens in a new tab), pricing (opens in a new tab), human in the loop (opens in a new tab), Slack (opens in a new tab), logs (opens in a new tab), permissions (opens in a new tab) and MCP (opens in a new tab) pages, and Hubzoid's docs. Both products change often, so check the current pages before you decide.
Why teams choose Hubzoid
- Rules you can read and review. A Hub is a folder. A rule change shows as a diff, and every surface uses the new rule.
- Team controls are open source. Per-person grants, approvals and the audit log need no enterprise subscription.
- Fully self-hosted. Chat, workflows and Settings all run on your server, with no Hubzoid service in between.
- Your assistant joins in. Claude Code connects over MCP as you, with the same knowledge and only the tools you may use.
Where Sim is stronger
- A polished visual builder that people who do not code can use.
- A large library of ready integrations, plus tables and files in the same workspace.
One task, built two ways
An operations team wants a weekly stock report, with a person approving any reorder above a set amount.
In Sim, someone builds it on the canvas: a schedule, a stock lookup block, an agent block for the summary and a Human block that pauses before the reorder.
In Hubzoid, the operations lead writes the stock definitions and the reorder threshold in the Hub, a coding assistant builds the lookup tool and workflow, and the workflow waits for a named approver. Teammates can also ask about stock in chat under their own access.
Other Sim alternatives
- n8n, a self-hostable workflow automation tool with AI nodes.
- Zapier and Make, hosted automation across many SaaS apps.
- Activepieces, an open-source automation tool.
If the work is mostly moving data between apps on a trigger, these may fit. If you need an agent that answers from your own knowledge and acts within each person's access, see internal AI agents.
Questions
Is Sim open source? Its repository is Apache 2.0, except enterprise features such as SSO, permission groups and audit logs, which need a Sim Enterprise subscription for production use. Hubzoid is Apache 2.0 throughout.
Can I self-host Sim? Yes, with Docker Compose or Helm. Its chat feature uses a key from Sim's own service even when self-hosted.
Get started
Build a small Hub in about five minutes with the quickstart, or read the code on GitHub (opens in a new tab).