components of KEP-2170, creating TrainingRuntime and Cluster-TrainingRuntime CRDs for JAX. Built on the Kubernetes JobSet API, these reusable blueprints simplify LLM and model training within cloud-native ML pipelines, letting AI practitioners submit jobs via SDK or YAML without managing low-level Kubernetes orchestration Takeaways • Simplified UX: scientists use high-level Python SDK references instead of complex YAML. • Reusability: blueprints can be curated by admins and consistently shared. • Framework-Agnostic: same API covers JAX, PyTorch, LLMs, and more. • Cloud-Native Scalability: leverages JobSet and Kubernetes for distributed execution. Python SDK Example from kubeflow.trainer import TrainerClient from kubeflow.trainer import CustomTrainer def jax_train_mnist(args): pass client = TrainerClient() jax_runtime = next( r for r in client.list_runtimes() if r.name == "jax-distributed" ) job_id = client.train( trainer=CustomTrainer( func=jax_train_mnist, func_args={"epoch": "10"}, num_nodes=4), runtime=jax_runtime, ) YAML using a Runtime Blueprint apiVersion: trainer.kubeflow.org/v1alpha1 kind: ClusterTrainingRuntime metadata: name: jax-distributed spec: mlPolicy: numNodes: 4 jax: backend: nccl template: spec: replicatedJobs: - name: process template: spec: template: spec: containers: - name: node image: kubeflow/jax-runtime Key Innovations from Trainer V2 • Unified CRDs: TrainJob, TrainingRuntime, and ClusterTrainingRuntime – replace framework-specific controller (e.g., JAXJob, PyTorchJob) with a single, flexible interface. • Reusable runtime blueprints let admins standardize compute environments, while practitioners simply reference them in TrainJobs. • Built on Kubernetes JobSet API, enabling scalable, multi-pod distributed training across TPU / GPU / CPU. • Full SDK support for programmatic job submission and management. Core Components • Kubernetes: container orchestration at scale. • Kubeflow Trainer V2: unified API with reusable runtime abstractions. • TrainingRuntime / ClusterTrainingRuntime: define environment and resources for training. • JAX: primary frameworks supported Mahdi Khashan Master’s of Artificial Intelligence at JKU Scalable ML on Kubernetes