Short answer
Looking for the best self-hosted ATS? Choose self-hosting when someone on your team can run the server, install updates, apply security releases, monitor failures, and restore backups.
Choose a cloud ATS when you need to start hiring without assigning an engineer to maintain recruiting software.
Self-hosting gives you direct control over the application and server. That control also makes your team responsible for uptime, security work, backups, and upgrades.
Cloud software moves that operating work to the vendor. You still need to assess access, security, workflow, and price, but your team does not maintain the application server.
For founders hiring without HR and independent recruiters, cloud is usually the practical fit. Technical teams may prefer self-hosting when they have a specific customization need and an engineer available after launch.
Why teams look at self-hosting
Control after losing access to a vendor account
Vendor account access can become a single point of failure.
One recruiter described the problem this way:
"I was using BreezyHR to manage candidates I was tracking. However, Breezy decided to disassociate my account from the company I was had setup and now I've pretty much lost all the data that I had inputted."
The same buyer asked:
"Is there a self-hosted option similar to breezy that I could setup? I've tried looking for open source alternatives, but couldn't' really find anything. Docker or VM is fine."
Self-hosting can give an operator direct control over the server and database. That control depends on working backups, documented access, and someone who knows how to recover the system.
Lower software fees
Some buyers compare self-hosted software with recurring vendor fees.
A technical buyer wrote:
"Greenhouse and Lever are good but are there any open source alternatives? I need one for my company but I don't want to spend the exorbitant amount and I want some customizations."
Open-source software can remove a software subscription. It does not remove hosting, setup, monitoring, upgrade, backup, and engineering costs.
A vendor blog estimates a basic virtual server at $5 to $20 per month and about half a day of setup for simpler tools. Treat that as cost color from a vendor, not a quote for every deployment.
Custom workflows
A self-hosted application can be modified when its license and architecture permit it. That can matter when a team has internal approval steps, unusual candidate fields, or integrations unavailable in a cloud product.
Each customization creates an upgrade decision. Your team must test whether local changes still work after upstream releases.
A simple candidate tracker
Some teams need a small shared record rather than a broad HR platform.
One buyer said:
"I don't need anything fancy, only an app to track all the candidates that we interview."
A simple requirement can favor a focused ATS. It can also reduce the value of running and maintaining your own server.
Buyer caution also shows up on the agency side:
"I'd be personally hesitant to get a self hosted or new system and trust my database to it."
What self-hosting really costs
The visible cost is the server. The larger cost is ownership. For published cloud plan prices, see our ATS cost guide and ATS pricing comparison.
A self-hosted ATS needs:
- A server or hosting account
- Initial installation and configuration
- Sign-in and access setup
- Backups and restore checks
- Monitoring for downtime and storage limits
- Application, runtime, and database updates
- Security release review and installation
- Time to diagnose failed upgrades
OpenCATS shows both sides of active open-source maintenance.
Its maintainers published 19 GitHub security advisories in 2026, including 2 critical, 7 high, and 10 medium advisories. Publishing advisories and fixes is evidence of active maintenance. Every relevant fix also becomes work that each operator must review, apply, and verify.
Examples from 2026 include:
- Missing authorization in candidate export could expose hidden candidate data, rated medium and published on October 22, 2026
- SQL injection in import column mapping, rated high and published on September 3, 2026
- Unauthenticated SQL injection in the installer, rated critical and published on September 2, 2026
- Authenticated remote code execution in the Import module, rated critical and published on June 14, 2026
OpenCATS documentation states that "there is no help desk that you can call for support". It also says that "because OpenCATS is open source software, security is your responsibility".
That responsibility is the central self-hosting cost. Installing version one is a project. Keeping it safe and available is an ongoing role.
Best self-hosted ATS options
OpenCATS is the only mature, dedicated self-hosted ATS in this comparison. It combines ATS and recruiting CRM functions, has a long operating history, and remains active in 2026.
Several dedicated projects are active but early, each with fewer than 50 GitHub stars as of November 9, 2026. Harly describes itself as a public beta. OpenATS, Vekt, and FreeATS also have small contributor and user signals compared with established HR suites.
Odoo Recruitment, Frappe HR, Horilla, and OrangeHRM place recruitment inside a wider HR application. They may fit teams that also want employee management modules. They require more evaluation when the immediate need is candidate tracking.
| Product | Type | License | Latest release or activity | GitHub stars | Maintained flag |
|---|---|---|---|---|---|
| OpenCATS | Dedicated ATS and recruiting CRM | MPL 2.0 plus older CATS license | v0.12.0, October 22, 2026 | 780 | Active in 2026 |
| OpenATS | Dedicated ATS | Apache-2.0 | v0.8.0, November 3, 2026 | 44 | Active, early |
| Harly | Dedicated ATS | MIT | v0.4.0, November 8, 2026 | 9 | Active, public beta |
| Vekt | Dedicated ATS | MIT | 1.2.11, November 4, 2026 | 8 | Active, early |
| FreeATS | Dedicated ATS | MIT | No GitHub release, last commit October 13, 2026 | 45 | Recent activity, early |
| Odoo Recruitment | HR suite module | Community edition LGPL-3 | Odoo 20, September 2026 | Not applicable | Actively developed |
| Frappe HR | HR suite | GPL-3.0 | v15.64.8, November 4, 2026 | 9,034 | Active |
| Horilla | HR suite | LGPL-2.1 | 2.3.1, November 8, 2026 | 1,502 | Active |
| OrangeHRM | HR suite | GPL-3.0 | v5.9, June 28, 2026 | 1,161 | Active |
CandidATS is abandoned. YAWIK and nueno are stale. They are not recommended for a new deployment.
Where Curriculo fits
Curriculo is cloud only. There is no self-hosted or on-premise edition.
It fits founders, independent recruiters, and small hiring teams that want an ATS without putting an engineer on call for recruiting infrastructure. See AI ATS for founders and Curriculo pricing.
Sign in with Google or Microsoft.
Curriculo uses TLS 1.2+ with TLS 1.3. Mailbox and calendar tokens use AES-256-GCM. Transport wording only; see security for the same claims.
Plans include:
- Starter, free forever
- Pro, $50 per month early-bird pricing, 50% off the standard $100 monthly price
- Enterprise, custom pricing
- No per-seat fees
- Teammates supported
- MCP in every plan
Available agents include Email, Calendar, Daily briefing, and Resume screening. The Calendar agent does not schedule interviews on its own.
AI can rank candidates with a written reason. A person decides what happens next.
With your Google or Microsoft calendar connected, your AI assistant can schedule the interview through Curriculo MCP: it creates the event, sends the invites, and adds the Meet or Teams link.
Curriculo fits when hiring work needs one place and server maintenance would distract the person running the company or desk.
Better hiring in less time.
You can also compare free ATS options, review Curriculo alternatives, check ATS cost, or read the ATS buyer's guide.
FAQ
Is a self-hosted ATS free?
The software may have no license fee. You still pay for hosting and the time required for setup, backups, monitoring, upgrades, and security releases.
Who should choose a self-hosted ATS?
Choose self-hosting when your team needs server control or deep customization and has someone responsible for maintenance, recovery, and security updates.
Who should choose a cloud ATS?
Choose cloud when you want to begin hiring quickly and do not have an engineer available to operate recruiting software.
Is OpenCATS still maintained?
Yes. OpenCATS released v0.12.0 on October 22, 2026 and published multiple security advisories during 2026. Operators must install applicable fixes.
Does Curriculo offer a self-hosted edition?
No. Curriculo is cloud only. It has no self-hosted or on-premise edition.
How much does Curriculo cost?
Starter is free forever. Pro is $50 per month at early-bird pricing, which is 50% off the standard $100 monthly price. Enterprise pricing is custom. There are no per-seat fees.
Can Curriculo schedule interviews?
Yes, only with a connected Google or Microsoft calendar through Curriculo MCP. The Calendar agent does not schedule interviews on its own. MCP creates the event, invites attendees, and adds a Google Meet or Microsoft Teams link.
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Sources
All sources checked November 9, 2026.
- OpenCATS GitHub repository
- OpenCATS website
- OpenCATS introduction and overview
- OpenCATS security advisories
- Candidate export authorization advisory
- Import column mapping advisory
- Installer advisory
- Import module advisory
- OpenATS
- Harly
- Vekt
- FreeATS
- Odoo Recruitment
- Odoo pricing
- Frappe HR
- Horilla
- OrangeHRM
- BreezyHR open-source alternatives discussion
- Open-source ATS discussion
- Simple applicant tracking request
- Agency caution on self-hosted systems
- Open-source ATS cost article, vendor blog
- Curriculo pricing
- Curriculo about