Founding Engineer

Company Description
EternUp is building the digital twin for human life — an AI operating system that connects your time, work, relationships, health, knowledge and finances into one continuously evolving model of you. Powered by Continuo, our personal context layer, EternUp understands not just what you ask for, but what's happening and what should happen next — then acts on it through Aeon, an AI chief of staff that coordinates specialized agents across your calendar, tasks, health, and logistics. We're the human side of a two-sided platform: the same digital-twin technology powers Twinamics for businesses. This is a new category, not a calendar app or a wellness tracker — and we're building the infrastructure for it from the ground up.
Role Description
As a Founding Engineer at EternUp, you'll design, build, and scale the core systems behind our digital twin: the context layer that ingests and models a person's life, the agent runtime that lets Aeon act safely on their behalf, and the day-design and task systems users touch every day. You'll work across a modern stack (Next.js/React, Postgres, agentic AI orchestration) and collaborate directly with the founders to turn product and architectural decisions into shipped, tested code. Day to day, this means high-quality backend and full-stack work, sound engineering judgment on what an autonomous agent should and shouldn't be allowed to do, and end-to-end ownership of features from spec to production. This is a full-time hybrid role based in the Kolkata metropolitan area, with a mix of on-site collaboration and flexible work-from-home days.
Qualifications
Full-stack engineering: strong TypeScript/JavaScript, React/Next.js on the frontend, Node/Postgres on the backend — able to build and ship a feature end-to-end alone
GUI/frontend craft: can build clean, responsive interfaces from scratch and implement a design system precisely (spacing, typography, states) — not just plug in a component library
Agentic systems, built not bolted on: has built agent loops, tool-calling, or orchestration logic from open-source frameworks or from scratch (LangGraph, CrewAI, custom loops) — not just prompting a hosted API and calling it done
Actuator/automation layer: experience building systems that take real-world actions on a user's behalf — action registries, permission gating, execution logs — using self-hosted or open-source tooling (e.g., browser automation via Playwright/CDP, not a paid automation SaaS)
Open-source-first instinct: default to self-hosting and open-source stacks (Postgres, open LLMs where viable, open queues/workers, open auth) over proprietary APIs and managed SaaS wherever it's practical
CI/CD and infra: can set up and maintain build/test/deploy pipelines (GitHub Actions or similar), containerization (Docker), and basic cloud infra without hand-holding
Systems/backend depth: comfortable with databases, auth, queues, and API design — not just frontend-adjacent scripting
Startup ownership: writes production-quality code fast, debugs down to root cause, and takes a feature from idea to deployed without needing a spec for every detail

Work arrangement
Hybrid