Senior Full Stack Engineer

Sphere is using AI to codify the world's international trade law.

We currently help companies like Lovable, Eleven Labs, Replit, Runway AI, Windsurf (+ many more) automate their sales tax, VAT and GST compliance:

• We're growing rapidly (30%+ MoM revenue growth) and helping the fastest growing tech companies around the world including Lovable, Eleven Labs, Replit, Windsurf, Deel, Linktree, Fal, Sierra AI etc

• We’ve spent the last 2 years building local rails into 100+ tax authorities across the world to properly automate compliance processes (no other vendor has done this)

• We're building the world's first AI-native tax engine (which will be the foundation for a broader cross border compliance platform; think Deel for revenue-based compliance)

• We're well funded by a16z, YC, 20vc and Felicis Ventures.

Sphere is looking for a versatile full stack engineer who can jump on different mission critical areas to help accelerate its production - e.g. filing infrastructure, tax engine and new product areas (input tax, withholding tax, e-invoicing).

These areas are key levers towards scaling Sphere and growing ARR, meaning that your work will have a direct impact on the growth of the business

Why this is a massive opportunity:

🌍 Massive TAM: Every business around the world needs this. Compliance isn’t optional.

🌬️ Strong macro tailwinds: Businesses are expanding globally at a faster pace, while tax authorities are cracking down on cross-border compliance, driving urgent demand.

✨ AI advantage: Incumbents can’t scale beyond the U.S.; our AI-native tax engine can.

🔮 Multi product play: Indirect tax is just the start; we’re building a compound startup that helps business with all forms of revenue-based compliance.

What you will do:
Within weeks:

• Ship features related to a key component of Sphere’s platform - e.g. filing infrastructure

• Own and manage this key component, driving measurable outcomes

• Work directly with customers like Eleven Labs, Replit and Windsurf to improve / optimize that key component of the platform (e.g. improve filing generation and submission speed [x]%)

Within months:

• Develop expertise across other key components of Sphere’s platform - e.g. tax engine, new products - to manage and execute improvements in this area

• Lead / mentor additional engineers in component areas that you have worked in
  

Requirements:

• Experience in Python . Our core application backend and data pipeline services are built with Python and Django

• While frontend / React may not be your primary focus, you’re not afraid to dive in when needed

• Very strong attention to detail. When you work with numbers this is a non-negotiable - it’s not enough to be 99% right.

Nice to have:

• Experience working with large volumes of transaction data. You’ll be getting very familiar with it!

• Experience with Django or Python ORM

What’s important to us:

• The Dog: Grit > pedigree.

• Ship fast: If it can be done today, do it today.

• Self-starter: No hand-holding

• Accountability: You’ll be held accountable to objective, measurable targets each month.

• In-person: SF only.

Sphere is building AI-native trade infrastructure. We help companies like Lovable, Eleven Labs, Replit and Deel automate their sales tax, VAT, GST compliance obligations.

What makes us different to other vendors on the market is:

1. we have spent the last 2 years building local rails into tax authorities in both the US and internationally to properly automate compliance processes (no other vendor has done this), and

2. we're building the world's first AI-native tax engine (which will be the foundation for a broader cross border compliance platform; think Deel for international billing).