Smit Kiri

Lead ML Infra EngineeratKlaviyo

Smit Kiri

I build and lead the ML infrastructure that powers Klaviyo's machine learning — Ray clusters running distributed compute across hundreds of nodes, serving platforms that compress deployment timelines from months to days, and the technical roadmaps that define how the platform evolves. My focus is on foundations that compound: infrastructure and strategy that multiply what ~40 ML engineers and data scientists can accomplish.

What I work on

Distributed Compute

Klaviyo's ML teams needed to run large-scale training and batch inference workloads across hundreds of nodes, reliably. I built DART Jobs, the compute platform that made this possible — powered by Ray Clusters on Kubernetes. It now handles 350–450 ML jobs per day on average, enabling research and production workloads that had no path to execution before this infrastructure existed. In 2025, a ground-up redesign of the platform drove a 7x increase in modeling runs and doubled the number of new users.

Model Serving

Deploying a new production online inference system used to require months of custom infrastructure work from individual teams. I built DART Online (DAtascience RunTime Online), a shared serving platform on Ray Serve that compressed that timeline to a few days. Teams get a reliable, scalable, observable path from trained model to production without rebuilding the foundation each time.

ML Platform & Tooling

The internal layer that multiplies what ML engineers and data scientists can do: experiment tracking with MLflow on Kubernetes, a model registry, VectorDB infrastructure, and model monitoring. I've also built CI/CD pipelines for ML workflows and contributed to a GitOps setup that condenses Kubernetes deployments to a single YAML — less friction between an idea and a production system.

Platform Strategy

Defining long-horizon technical direction for Klaviyo's ML platform — authoring roadmaps for distributed compute, model serving, and the broader 2026 ML Platform Vision. I also work across engineering teams to review system designs and ensure the ML platform coheres with infrastructure direction at the company level.

ML Orchestrationin progress

Currently building end-to-end ML pipeline orchestration with Prefect — bringing structured scheduling, dependency management, and observability to the full ML lifecycle, from data ingestion through model deployment.

Selected work

Reinventing Klaviyo's compute platform

2025

DART Jobs had been running successfully for two years, but its underlying architecture had limits that constrained how ML teams could use it. I led the ground-up redesign: defining the system architecture, evaluating tradeoffs, and serving as technical lead through execution. DART Jobs V2 drove a 7x increase in modeling runs and doubled the number of new users on the platform, unlocking a new generation of ML-powered products that weren't feasible before.

DART becomes Klaviyo's ML foundation

2024

By 2024, DART had grown from infrastructure into institution — 40 systems across 6 teams running on the platform. Teams that had spent months building custom deployment pipelines were instead shipping models in days. One team achieved a 10x speed-up in model training, another migrated ~10 models and shut down their legacy deployment system entirely, and a third deployed a suite of new compliance models that had no path to production before DART existed.

Distributed ML compute at Klaviyo

2023

Distributed training and large-scale batch inference across hundreds of nodes wasn't possible with Klaviyo's existing infrastructure. I built DART Jobs, the platform that changed that — covering cluster provisioning, job scheduling, fault tolerance, and observability, all running on Ray and Kubernetes. DART Jobs now handles 350–450 ML jobs per day and has become the foundation for Klaviyo's most compute-intensive research and production workloads.

From three months to three days

2023

At Klaviyo, each ML team was building its own serving infrastructure from scratch. The process was slow, duplicated across teams, and pulled engineers away from model development. I designed and built DART Online, a shared inference platform on Ray Serve that standardized the path from trained model to production. Standing up a new serving endpoint went from a months-long engineering effort to a matter of days.

Personal projects

EHR Relation Extraction↗

91 ★ · 32 forks

Named Entity Recognition and Relation Extraction from Electronic Health Records. Uses BioBERT for entity recognition and a BiLSTM-CRF architecture to extract relationships between medical entities like drugs, adverse events, and dosages from clinical text.

News QA↗

11 ★ · 2 forks

A reading comprehension based question-answering model for news articles. Built with BERT and DistilBERT transformer models in PyTorch, trained on the Microsoft NewsQA dataset.

Writing & talks

Patents