[Bug]: Docker source builds fail on Coolify Cloud with “BuildKit is enabled but the buildx component is missing or broken” even though buildx is installed and working on the connected server

[saishiki]

Error Message and Logs

We are using Coolify Cloud and deploying to our own connected server over SSH.

Any source-based Docker build fails almost immediately with this error:

ERROR: BuildKit is enabled but the buildx component is missing or broken.
Install the buildx component to build images with BuildKit:
https://docs.docker.com/go/buildx/

Relevant deployment log:
Docker 28.5.2 with BuildKit and Buildx detected on deployment server (core-16gb-2cpu).
Starting deployment of saishiki/hermes-workspace:main to core-16gb-2cpu.
Preparing container with helper image: ghcr.io/coollabsio/coolify-helper:1.0.13

Importing saishiki/hermes-workspace:main (commit sha 40799a8a66e0f3d8cd8634beed4cbe31bb4521dd) to /artifacts/ufb761b5tewncq1qfqkby3qu.
Image not found (wb8mevfgqte2t94gqgpmlmhi:40799a8a66e0f3d8cd8634beed4cbe31bb4521dd). Building new image.

Building docker image started.

Deployment failed: Command execution failed (exit code 1): docker exec ufb761b5tewncq1qfqkby3qu bash -c 'bash /artifacts/build.sh'
Error: ERROR: BuildKit is enabled but the buildx component is missing or broken.
Install the buildx component to build images with BuildKit:
https://docs.docker.com/go/buildx/

Deployment failed. Removing the new version of your application.

The issue is not app-specific. I created an entirely new project and got the same failure during the build step.

Steps to Reproduce

1. Use Coolify Cloud with a connected Ubuntu deployment server over SSH.
2. Create a new application from a GitHub repo that requires a Docker build from source.
3. Start deployment.
4. Build fails almost immediately inside the helper/build flow with:
   BuildKit is enabled but the buildx component is missing or broken.

Coolify Version
v4.0.0-beta.473

Are you using Coolify Cloud?
Yes (Coolify Cloud)

Operating System and Version (self-hosted)
Ubuntu 24.04

Additional Information
I verified this on the connected deployment server itself:

• docker buildx version works
• docker buildx ls shows a running default builder
• the docker-buildx plugin exists on disk

Example output after testing and even downgrading Docker:
docker version
Client: Docker Engine - Community
Version: 28.5.2

Server: Docker Engine - Community
Engine:
Version: 28.5.2

docker buildx version
github.com/docker/buildx v0.33.0 f7897eba028583e0071642db3c011e860444f8cf

docker buildx ls
NAME/NODE DRIVER/ENDPOINT STATUS BUILDKIT PLATFORMS
default* docker
_ default _ default running v0.25.2 linux/amd64 (+4), linux/386

The plugin is present here:

/usr/libexec/docker/cli-plugins/docker-buildx

I originally tested on Docker 29.4.0, then downgraded the host to Docker 28.5.2 and restarted Docker. Coolify now correctly reports:
Docker 28.5.2 with BuildKit and Buildx detected on deployment server

But the deployment still fails with the exact same BuildKit/buildx error inside the helper/build step.

This makes it look like the issue is in the Coolify Cloud helper/build path rather than the connected server’s actual Docker/buildx installation.

Steps to Reproduce

1. Sign in to Coolify Cloud and connect a fresh Ubuntu 24.04 server over SSH as a deployment target.
2. On the connected server, confirm Docker and Buildx are installed and working:
   • docker version
   • docker buildx version
   • docker buildx ls
3. In Coolify Cloud, create a new application from a GitHub repository that uses a Dockerfile and must be built from source on the connected server.
4. Use a normal source-based deployment flow, not a prebuilt image.
5. Start the deployment.
6. Wait until Coolify finishes:
   • preparing the helper container
   • importing the repo into /artifacts/...
   • starting the Docker image build step
7. Observe that the deployment fails almost immediately during the build step with:
   • ERROR: BuildKit is enabled but the buildx component is missing or broken.
8. Repeat the same test with:
   • a different repo
   • or a brand new throwaway project
9. Observe that the failure is the same, which suggests the issue is not repository-specific.
10. Optional verification:
    • downgrade the connected server from Docker 29.x to Docker 28.5.2
    • restart Docker
    • confirm docker buildx version and docker buildx ls still work on the server
    • retry deployment
11. Observe that Coolify still fails with the same BuildKit/buildx error even though Buildx works normally on the connected host.

I reproduced this with multiple projects, including a fresh new project, and the failure always occurs in the Coolify helper/build flow before the app image is actually built.

Example Repository URL

No response

Coolify Version

v4.0.0-beta.473

Are you using Coolify Cloud?

Yes (Coolify Cloud)

Operating System and Version (self-hosted)

Ubuntu 24.04

Additional Information

No response

[coderabbitai]

🔗 Related PRs

#6689 - v4.0.0-beta.430 [merged]
#6755 - v4.0.0-beta.434 [merged]
#8565 - fix(deploy): split BuildKit and secrets detection [merged]

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[leftclickag]

same issue on seflhosted for me with the latest version