fetching via SSH fails

[krauterbaquette]

I have a private repo I want to build with gradient.
Therefore I've given gradient access via a ssh key (services.gradient.organizations.<name>.private_key_file = "/run/id_ed25519"), however gradient still fails to fetch the repository with the error shown below

failed to clone git+ssh://forgejo@git.example.com:16682/krauterbaquette/config.git: authentication required but no callback set; class=Ssh (23); code=Auth (-16)

I am using gradient version 1.2.2 (60bc60c7aa7a3a938fa2598764d1917580b17f23)

[DerDennisOP]

have you tested using the ssh key and clone it manually?

[krauterbaquette]

yes, I have verified that I can

1. access the server via ssh
2. clone the repo via ssh

both with the provided private key

[DerDennisOP]

Your worker should have a debug printout something like: fetching repository url=... has_ssh_key=false

[krauterbaquette]

I cannot find any logs containing fetching repository.
I will try to reproduce the error again to find new logs later this evening / tomorrow.

The only logs I can currently find which match the time are these:

Mai 20 11:44:16 galio gradient-worker[415290]: 2026-05-20T09:44:16.759804Z  INFO gradient_worker::worker::dispatch: job assigned — accepting job_id=eval:019e44c5-732e-7112-bf49-987911de0fbd kind=Flake
Mai 20 11:44:19 galio gradient-worker[415290]: 2026-05-20T09:44:19.303139Z  INFO gradient_worker::executor::fetch: repository cloned path=/tmp/gradient-fetch-019e44c5-887a-7630-9068-06f182bcdc62 commit=1aaf2212d12e2b6a83cf20facf36e57be65b707a
Mai 20 11:44:20 galio gradient-worker[415290]: 2026-05-20T09:44:20.278563Z  INFO execute_flake_job{tasks=[FetchFlake, EvaluateFlake, EvaluateDerivations]}: gradient_worker::executor::fetch: flake archived to nix store source_path=/nix/store/x6ln20gw52qpd0ckav2zwxhyh8ia8lhd-sour>
Mai 20 11:44:20 galio gradient-worker[415290]: 2026-05-20T09:44:20.333263Z  INFO execute_flake_job{tasks=[FetchFlake, EvaluateFlake, EvaluateDerivations]}: harmonia_store_remote::client: Client Version is 1.38, server version is 1.38 version=ProtocolVersion(1, 38) server_versio>
Mai 20 11:44:20 galio gradient-worker[415290]: 2026-05-20T09:44:20.333474Z  INFO execute_flake_job{tasks=[FetchFlake, EvaluateFlake, EvaluateDerivations]}: harmonia_store_remote::client: Nix Version "2.34.7" version="2.34.7"
Mai 20 11:44:20 galio gradient-worker[415290]: 2026-05-20T09:44:20.729829Z  INFO execute_flake_job{tasks=[FetchFlake, EvaluateFlake, EvaluateDerivations]}: gradient_worker::proto::nar: direct NAR push complete store_path="/nix/store/x6ln20gw52qpd0ckav2zwxhyh8ia8lhd-source" comp>
Mai 20 11:46:26 galio systemd[1]: gradient-worker.service: The kernel OOM killer killed some processes in this unit.

The commit matches the repository I could not clone in this bug report, but from the logs it seems like the fetch was successfull but the maschine gut OOM-killed later on in the eval(?) which is a bit weird - I will try to produce clean logs again