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# Senior Founding Engineer

- **Company:** Arc Full-time
- **Location:** United States (Remote available)
- **Experience:** Expert
- **Salary:** $100,000.0 - $220,000.0
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, Business Logic, BigQuery, Spreadsheets, Cursor, Github, Python (Programming Language), PostgreSQL, Netsuite, Next.js, Shopify, Software Factory, TypeScript, Tailwind, ReactJS, Claude Code, Snowflake, Grafana, Backend, Fastapi, Front End Software Development, Vertica, Xero (Accounting Software), Software Version Control, Amazon Redshift
- **Published:** October 27, 2026
- **Apply:** https://arc.dev/signup?userType=developer&publicRandomKey=puuljfe058&to=https%3A%2F%2Farc.dev%2Fdashboard%2Fd%2Fverified-jobs%2Fpuuljfe058%2Fapplication

## About the Role

* Backend in Python. 4+ years of experience in production. FastAPI / asyncio fluency. You spot event-loop blockers in review.
 * Frontend in TypeScript. 3+ years of experience shipping real Next.js or React.
 * Operating velocity. AI-assisted dev as default - Claude Code, Cursor, Codex. You dream of building a software factory.

## Description

We're looking for an experienced engineer who wants to solve hard problems, write the code, and help shape both the platform and the company.

You'll wear many hats: architect, product engineer, data engineer, SRE, FDE, AI engineer, and the person who digs into a production failure and fixes it properly. One week you might redesign how we connect a new data source; the next, ship an agent capability or make our infrastructure ready for the next wave of customers. You'll take work from an ambiguous problem to a solution customers depend on.

And you'll raise the bar for engineering excellence. Through the systems you build, the decisions you challenge, and the standards you put into practice, you'll help us become a team that consistently ships exceptional work. We want your experience, your judgment, and your ambition in the room - and your code in production.

## What You'll Actually Build

You'll help us solve hard engineering problems including:

 * Enterprise integrations, productized. NetSuite, Shopify, Xero, Walmart, Target, Amazon, ShipHero, and many more - wrapped behind one provider interface and exposed to the agent through MCP, with in-loop credential refresh.
 * Orchestration that never drops the ball. Schedules, retries, durable execution, full run history, replay, alerts, version control. Every workflow is observable and recoverable - so a Wednesday failure isn't discovered on Friday.
 * Ontology - the brand's business model in writing. A queryable, governed source of truth for what each customer actually means by "forecast", "SKU", or "fiscal year-end". Mappings, calendar rules, metric definitions, constraints, full lineage back to the source file and download time. You'll design the schema and the APIs agents query against it - so business logic stops being re-derived in every spreadsheet.
 * The agentic layer. Build agents that identify sales gaps, make plans, optimize scenarios, and propose actions, eventually executing them too. Make improvement recursive: outcomes and corrections feed evaluations, validated improvements strengthen the next run, and the cycle repeats.
 * Observability across the stack. A turn's full lifecycle inspectable from a single trace ID across Vercel, Render, Daytona/Blaxel, etc.

## The Stack

 * Backend: Python 3.12, FastAPI, React Server Actions, Next.js, MCPs, Eve Agent Harness, vector databases
 * Frontend: Next.js 16, React 19, Vercel AI SDK, Tailwind, shadcn, Vercel
 * Data: Supabase / Postgres, Analytical DB agnostic (Snowflake, Bigquery, Redshift, Clickhouse, etc)
 * Sandboxes: Vercel sandboxes
 * External: Anthropic, AgentMail
 * Observability: Grafana
 * Repo: Turborepo, pnpm, GitHub Actions, isolated PR previews (frontend + backend + DB branch per PR)

## What We're Looking For

You're a great fit if:

 * You've done this before. You helped take a startup from pre-seed or seed to Series A or B. You personally built the systems that carried it through that growth and can explain where they held up, where they failed, and what you changed.
 * You design systems, not just features. You've given a growing codebase clear module boundaries and small interfaces. You can defend a design against a credible alternative and recognize when the alternative wins.