Senior Infrastructure Engineer

About JustAI

Agentic Marketing Platform

Tech description:

Job description:

## Infrastructure Engineer

We move terabytes of campaign and engagement data, and you'd own the foundation it all runs on.

**About JustAI**

We're a YC-backed team building the AI platform that runs marketing for the world's best companies. Marketers describe a campaign in plain language, and our platform turns it into running code that generates, tests, and executes personalized messaging across email and push at scale.

**The founders**

We were at X during the Elon takeover. I had to rewrite the backend infrastructure that now powers the core user and tweet services. You'll get to work closely with us.

**The role**

You'll own the foundation everything runs on: the large-scale data pipelines that feed our analytics and models, the compute and storage substrate, and the reliability, observability, and cost of the whole system. This is an early, high-ownership role. You'll be building a lot from 0→1 and owning it end to end as we scale.

**What you'll do**

* Own and scale our data infrastructure, including large-scale batch and streaming pipelines, warehouse design, and the storage layer behind them.
* Run and harden our compute platform: orchestration, autoscaling, resource isolation, and deployment of containerized workloads.
* Own the observability and reliability backbone (metrics, tracing, alerting, SLOs) and drive down both incidents and cost.
* Tackle the lowest-level scaling problems: data partitioning, throughput, query and scan cost, and distributed-systems failures at volume.
* Accelerate how quickly other engineers can ship code safely.

**What we're looking for**

* 5+ years in infrastructure, SRE, or data platform roles, with hands-on experience building and operating large-scale systems at a low level.
* A 0→1 builder. You've stood up infrastructure from scratch and owned it as it grew, not just maintained someone else's.
* Battle scars from lower-level, large-scale systems. You've run things like Kubernetes, Spark/Hadoop-class data processing, distributed storage, or high-throughput streaming in production.
* A track record of debugging hard problems at scale across failures, cost, and performance.
* Strong instincts for reliability, cost, and operability. You treat infra as a product with users.
* We care more about whether you've operated systems at scale than which specific tools you've used.
* Experience with machine learning systems a plus.

Skills:

Amazon Web Services (AWS), Google Cloud, Kubernetes, PostgreSQL, Python, TypeScript, Spark