The "Kubernetes Tax" on Modern Machine Learning
If you’ve ever tried setting up Kubeflow on Kubernetes, you know the drill:
- 30+ Custom Resource Definitions (CRDs)
- Istio Service Mesh + Knative + Cert-Manager + Dex
- 16 GB to 32 GB of RAM consumed before you even write a single line of Python
- Days spent debugging webhook admission controllers and Kustomize overlays.
Kubernetes is great at hyper-scale, but for 95% of engineering teams, researchers, and startups, Kubernetes for MLOps is massive over-engineering.
What if you could have the exact same capabilities — Interactive JupyterLab with PyTorch, MLflow Experiment Tracking, MinIO S3 Object Storage, and High-Speed LLM Inference — deployed in 60 seconds using a single
docker-compose.yml? Enter Gubernator (gbnt): the lightweight "Goldilocks" container orchestrator. ---
What is Gubernator?
Gubernator is a single-binary container orchestrator written in Go that combines:
- The simplicity of Docker Swarm (pure Docker Compose syntax, easy multi-node clustering).
- The power of Nomad (intelligent task scheduling, worker-first load balancing, and GPU hardware targeting).
- Built-in Aqueducts: Automatic CoreDNS service discovery + multi-node Caddy Ingress with automatic HTTPS/TLS.
4. The Granaries: Persistent shared storage mobility (/var/contenedores) across cluster nodes.
Architecture: Kubernetes Kubeflow vs. Gubernator MLOps
┌─────────────────────────────────────────────────────────────┐ │ Data Scientist / AI Engineer │ └──────────────────────────────┬──────────────────────────────┘ │ (https://*.kubeflow.gbnt.local) ▼ ┌─────────────────────────────────────────────────────────────┐ │ Built-in Caddy Ingress & CoreDNS Gateway │ └──────┬──────────────┬──────────────┬──────────────┬─────────┘ │ │ │ │ ▼ ▼ ▼ ▼ ┌──────────────┐┌──────────────┐┌──────────────┐┌──────────────┐ │ JupyterLab ││ MLflow ││ MinIO S3 ││ Ollama / vLLM│ │ Workspace ││ Tracking ││ Artifacts & ││ Inference │ │ (PyTorch) ││ & Registry ││ Datasets ││ Serving │ │ (:8888) ││ (:5000) ││ (:9001) ││ (:11434) │ └──────────────┘└──────────────┘└──────────────┘└──────────────┘
| Capability | Kubernetes Kubeflow | Gubernator MLOps (kubeflow-stack) |
|---|---|---|
| Control Plane Overhead | 16 GB – 32 GB RAM (etcd, Istio, K8s) | < 200 MB RAM (Go binary) |
| Configuration Format | Helm / Kustomize / CRD manifests | Standard docker-compose.yml |
| Deployment Time | 30–45 minutes | < 60 seconds |
| Experiment Tracking | Katib + Kubeflow Metadata | MLflow Tracking + Model Registry |
| Artifact Store | MinIO on PVCs | MinIO S3 with Granaries Storage |
| Inference Serving | KServe + Knative + Istio | Ollama / vLLM (OpenAI API compatible) |
| Domain Routing & TLS | VirtualServices + IngressGateway | Automatic Caddy Ingress (*.local) |
The Blueprint: Single-File MLOps Platform
Here is the entire stack defined in standard Docker Compose syntax:
version: "3.8"
services:
# 1. MinIO S3 Object Storage (Datasets & Model Checkpoints)
minio:
image: minio/minio:latest
restart: unless-stopped
command: server /data --console-address ":9001"
environment:
- MINIO_ROOT_USER=kubeflow
- MINIO_ROOT_PASSWORD=gubernator123
ports:
- "9000:9000"
- "9001:9001"
volumes:
- /var/contenedores/kubeflow/minio_data:/data
labels:
- "ingress.host=minio.kubeflow.gbnt.local"
- "gbnt.caddy.port=9001"
- "gbnt.service.name=minio-s3"
# 2. MLflow Tracking Server & Model Registry
mlflow:
image: ghcr.io/mlflow/mlflow:latest
restart: unless-stopped
command: >
mlflow server
--host 0.0.0.0
--port 5000
--workers 1
--allowed-hosts "*"
--backend-store-uri sqlite:////data/mlflow.db
--default-artifact-root s3://mlflow-artifacts/
environment:
- AWS_ACCESS_KEY_ID=kubeflow
- AWS_SECRET_ACCESS_KEY=gubernator123
- MLFLOW_S3_ENDPOINT_URL=http://minio.kubeflow.gbnt.local
- MLFLOW_S3_IGNORE_TLS=true
- MLFLOW_ALLOWED_HOSTS=*
ports:
- "5000:5000"
volumes:
- /var/contenedores/kubeflow/mlflow_data:/data
labels:
- "ingress.host=mlflow.kubeflow.gbnt.local"
- "gbnt.caddy.port=5000"
- "gbnt.service.name=mlflow-tracking"
# 3. Interactive JupyterLab & PyTorch Workspaces
jupyter-workspace:
image: quay.io/jupyter/pytorch-notebook:latest
restart: unless-stopped
environment:
- JUPYTER_TOKEN=gubernator-secret
- JUPYTER_ENABLE_LAB=yes
- AWS_ACCESS_KEY_ID=kubeflow
- AWS_SECRET_ACCESS_KEY=gubernator123
- MLFLOW_TRACKING_URI=http://mlflow.kubeflow.gbnt.local
- MLFLOW_S3_ENDPOINT_URL=http://minio.kubeflow.gbnt.local
ports:
- "8888:8888"
volumes:
- /var/contenedores/kubeflow/workspaces:/home/jovyan/work
- /var/contenedores/kubeflow/cache:/home/jovyan/.cache
labels:
- "ingress.host=notebooks.kubeflow.gbnt.local"
- "gbnt.caddy.port=8888"
- "gbnt.service.name=jupyterlab"
# 4. Model Serving & LLM Inference Gateway
inference-engine:
image: ollama/ollama:latest
restart: unless-stopped
ports:
- "11434:11434"
volumes:
- /var/contenedores/kubeflow/models:/root/.ollama
labels:
- "ingress.host=inference.kubeflow.gbnt.local"
- "gbnt.caddy.port=11434"
- "gbnt.service.name=model-serving"
🛠️ Deploying in 1 Command
On your Gubernator cluster, run:
gbnt stack deploy kubeflow-stack -c docker-compose.yml
Or open the Gubernator Web Dashboard (http://localhost:4001), head over to Compose Studio, select the Kubeflow MLOps Blueprint, and click Deploy Stack.
Gubernator's scheduler automatically:
Prioritizes Centurion Worker nodes over the Manager.
Spreads the workloads evenly across available workers.
Automatically sets up internal DNS (CoreDNS) and reverse proxy routes (Caddy Ingress).
Generates instant TLS certificates for all services.
Instant Endpoints & Access
Immediately after deployment, your MLOps platform is ready:
JupyterLab Workspace: https://notebooks.kubeflow.gbnt.local (Token: gubernator-secret)
MLflow Experiment Tracking: https://mlflow.kubeflow.gbnt.local
MinIO S3 Console: https://minio.kubeflow.gbnt.local (User: kubeflow / Pass: gubernator123)
⚡ Ollama Inference Engine: https://inference.kubeflow.gbnt.local (OpenAI-compatible /v1/chat/completions)
🧪 Testing the End-to-End Pipeline in Python
Data scientists can write normal Python code to log experiments, save models to MinIO S3, and serve predictions:
import mlflow
import mlflow.sklearn
from sklearn.ensemble import RandomForestClassifier
from sklearn.datasets import load_iris
import os
# Connect to the cluster's MLflow server
os.environ["MLFLOW_S3_ENDPOINT_URL"] = "http://minio.kubeflow.gbnt.local"
os.environ["AWS_ACCESS_KEY_ID"] = "kubeflow"
os.environ["AWS_SECRET_ACCESS_KEY"] = "gubernator123"
mlflow.set_tracking_uri("http://mlflow.kubeflow.gbnt.local")
mlflow.set_experiment("iris-classification-demo")
with mlflow.start_run():
X, y = load_iris(return_X_y=True)
clf = RandomForestClassifier(n_estimators=100, max_depth=4)
clf.fit(X, y)
# Log metrics
accuracy = clf.score(X, y)
mlflow.log_param("n_estimators", 100)
mlflow.log_metric("accuracy", accuracy)
# Persist model to MinIO S3 and register
mlflow.sklearn.log_model(clf, "model", registered_model_name="IrisProductionModel")
print(f"✅ Training completed! Accuracy: {accuracy * 100:.2f}%")
`
Key Takeaways
You don't always need Kubernetes: If you are not running hundreds of parallel multi-step distributed DAG pipelines with Argo, Kubernetes adds unnecessary friction and cost.
Standard Compose is enough: With an orchestrator like Gubernator, you get clustering, load balancing, health checks, automated Ingress, and persistent storage using simple, familiar Docker Compose files.
Resource Efficiency: You save 10x-20x the RAM, allowing you to invest your hardware budget where it actually matters: GPUs and model training.
🔗 Project Links
🐙 GitHub Repository: mario-ezquerro/gubernator
📖 Documentation: Gubernator Docs
⭐ Give it a star on GitHub if you found this useful!
Top comments (1)
Interesting approach. I think the strongest part here is not really “Kubeflow without Kubernetes”, but reducing the operational overhead for teams that simply don’t need the full Kubernetes ecosystem.
Compose + a lightweight scheduler makes a lot of sense for smaller MLOps deployments, especially when the main requirements are storage, experiment tracking, notebooks and inference.
The part I’d be interested in testing in production is failure handling: GPU scheduling, node failure, persistent volume recovery, rolling upgrades, and what happens to an MLflow/MinIO workload during rescheduling. Those are usually where the gap between a simple deployment and a production platform becomes visible.
If Gubernator handles those cases cleanly while keeping the Compose workflow this simple, that’s a pretty compelling middle ground.
Would be interested to compare notes on the architecture and where you see the boundary between Gubernator and Kubernetes as the workload grows.