Senior+ Backend Engineer

Hapiko; New York (NY); On-site; USD 150,000 - 250,000; Full time

Job summary

Dormont Manufacturing Co is looking for a Backend Engineer in New York to own and scale their real-time infrastructure for the Stickerbox product. This role involves architecting systems for managing audio pipelines and connecting numerous devices effectively.

The ideal candidate will bring 5+ years of backend development experience, primarily in Python, and familiarity with technologies such as FastAPI and PostgreSQL. We value a collaborative work environment and provide flexibility for on-site work in our Brooklyn office.

Qualifications

• 5+ years building and shipping backend systems in Python.
• Deep experience with FastAPI and asyncio patterns.
• Strong PostgreSQL skills, including schema design.

Responsibilities

• Architect and maintain systems connecting thousands of devices.
• Manage real-time audio pipelines and power user experiences.
• Design and optimize distributed job systems and APIs.

Skills

Backend system development

Python

FastAPI

PostgreSQL

Redis

DevOps practices

Tools

Docker

Elixir/Phoenix

Job description

Own, evolve, and scale the real‑time infrastructure behind Stickerbox: an AI-powered voice‑to‑sticker printer already serving thousands.

About Hapiko

Hapiko is a Brooklyn‑based company building the future of play.

Description

Founded by Arun Gupta (former CEO of Grailed, which sold to GOAT Group in 2022) and Bob Whitney (Anthropic, NYT Games), we’re on a mission to create safe, hands‑on AI experiences that fuel kids’ imaginations rather than replace them.

Our first product, Stickerbox, is the world’s first voice‑to‑sticker printer. A device that instantly transforms a child’s spoken ideas into printable, colorable stickers. We sold out our first run shipping for the holidays, and additional batches beyond that. It’s already being called “one of the first products to make AI feel magical for kids and grounded for parents.”

We have a $7M funding round led by Maveron (backers of Lovevery), Serena Ventures, and Ai2 (The Allen Institute). Stickerbox is already in homes bringing imagination to life for kids nationwide!

Why are we hiring?

The technical challenge is real. We’re running real‑time streaming, processing thousands of concurrent connections from IoT devices, and orchestrating ML pipelines that return magical responses in seconds or less. Our hybrid Python‑Elixir architecture handles everything from device authentication to job queuing to image delivery, all with the reliability parents expect and the speed kids demand.

We need a Backend Engineer to own and evolve this infrastructure. You’ll architect and maintain the systems that connect thousands of devices, manage real‑time audio pipelines, and power the experiences that make everything just work. This is a foundational role where your decisions will shape how we grow from thousands to millions of users.

What you’ll ship

Real‑Time Infrastructure

• IoT with audio streaming that handles tens of thousands (on our way to millions) of concurrent device connections
• Distributed job systems with Redis queues and pub/sub
• Optimized pipelines for GenAI at high RPM with sub‑second latency
• Monitoring and observability to keep our infrastructure healthy

APIs & Services

• FastAPI services for device auth, user management, and webhook integrations
• Secure RESTful APIs that are a joy to work with
• Reliable integrations with external ML services
• Data pipelines that feed our evaluation systems

DevOps & Reliability

• CI/CD pipelines that give the team confidence to ship fast
• Architecture decisions that balance performance, cost, and maintainability
• Alerts, runbooks, and on‑call practices that let the team sleep at night

You’re a great fit if you have

• 5+ years building and shipping backend systems in Python
• Deep experience with FastAPI and asyncio patterns
• Strong PostgreSQL skills, including schema design
• Hands‑on experience with Redis (caching, queues, pub/sub)
• Track record of designing reliable distributed systems
• A DevOps mindset, comfortable deploying, monitoring, and scaling
• Experience with GenAI/LLM pipelines deployed in production
• Clear communication skills; can translate technical tradeoffs for the team

Bonus if you have

• Worked with Elixir/Phoenix and enjoy managing concurrency
• Built software for IoT or custom hardware devices
• Managed real‑time systems and streaming data
• Experience with streaming protocols and media formats
• Tuned ML pipelines with prompt engineering and evals

Our stack

• Backend: Python, FastAPI, Elixir/Phoenix
• Data: PostgreSQL, Redis
• Infra: Docker

Location: NYC only, On‑site (flexible on WFH but we like to be in office the majority of the week) in our Brooklyn based office, close to most major train lines.

Salary

$150,000 - $250,000 per year