Open source · Containers & runtimes
Open-source containers & runtimes
There are 5 open-source containers & runtimes worth knowing about, led by Podman and containerd. They are most often used to replace Docker. All can be self-hosted, which removes per-seat pricing entirely — but only pays off if someone on your side will own updates, backups and security patches.
Reviewed 2026-07-28 All open-source alternatives How we compare Full catalog
The projects
| Project | What it is | Commonly replaces | Source |
|---|---|---|---|
| Podman | Daemonless, rootless containers with a Docker-compatible CLI. | Docker | repo ↗ |
| containerd | The runtime Docker and Kubernetes actually use underneath. | Docker | repo ↗ |
| Incus | System containers and VMs; a community fork of LXD. | Docker | repo ↗ |
| Buildah | Builds OCI images without a daemon or a Dockerfile. | Docker | repo ↗ |
| Colima | Container runtimes on macOS without Docker Desktop's licence. | Docker | repo ↗ |
Docker 
Don't self-host if…
- Nobody has agreed to own patching — an unmaintained service facing the internet is a liability
- You have never tested restoring from a backup of anything
- The tool would hold data whose loss would genuinely hurt, with no second copy
- Your team's time is worth more than the subscription you are trying to avoid
We list these because they are often the right answer. We say this because they are not always the right answer.
Questions people actually ask
What is the best open-source container?
Podman is the most widely deployed of the 5 projects here — daemonless, rootless containers with a docker-compatible cli. The honest answer depends less on features than on operations: the best one is whichever your team will actually keep patched and backed up.
Are open-source containers & runtimes really free?
The software is free; running it is not. Budget roughly $5–20 a month for a small server, plus your own time for updates, backups and security patching. You are swapping a subscription for maintenance work, which is a good trade only if someone will actually do the work.
Can I self-host without a sysadmin?
Often yes, with Docker and a managed VPS. Several of these projects also sell a hosted version, which keeps the open-source licence and data-ownership benefits without the maintenance burden — at that point you are comparing their price against the commercial incumbent's.
Is open source safe for business use?
Widely deployed open-source software is not inherently less secure — the code is inspectable, which is an advantage. The genuine risk is operational: an unpatched self-hosted service facing the internet is far more dangerous than a maintained SaaS product. Security depends on your discipline, not the licence.
Other open-source roundups
- Open-source cloud storage & file sync 4
- Open-source helpdesk & ticketing 4
- Open-source password managers 4
- Open-source accounting & invoicing 3
- Open-source CRM & sales 4
- Open-source workflow automation 4
- Open-source monitoring & observability 6
- Open-source team chat 4
- Open-source project management 7
- Open-source notes & knowledge 8
- Open-source no-code databases 5
- Open-source API clients 3
- Open-source identity & SSO 5
- Open-source hosting & PaaS 4
- Open-source web analytics 4
- Open-source design & whiteboards 3
- Open-source CMS & site builders 3
- Open-source BI & dashboards 4
- Open-source e-commerce 4
- Open-source AI agent frameworks 10
- Open-source graphics & photo editing 4
- Open-source git hosting 3
- Open-source website builders 3
- Open-source AI chat assistants 3
- Open-source AI coding assistants 6
- Open-source AI image generation 3
- Open-source AI voice, speech & music 3
- Open-source vector databases 6
- Open-source LLM gateways & observability 5
- Open-source local LLM runners 5