Full Stack AI Developer (Python/React)

Filed; Stockholms kommun; On-site; SEK 767,000 - 907,000; Full time

Benefits offered by this job

30 days holiday per year (Europe/US)

Company-wide offsites every four meses

Fully covered medical expenses for US"

Job summary

Filed is an AI tax preparer redefining industry transparency and accountability. As a Fullstack AI Developer, you will build the agentic systems at the core of Filed, delivering probabilistic models that professionals trust for high‑stakes tax work, with clear ownership and rapid iteration.

You’ll work on groundbreaking workflows that mirror how tax professionals operate, ensuring accuracy, verifiability, and a superior user experience while collaborating across product and engineering teams.

Qualifications

• Experience building data-heavy UIs and backend services.
• Experience with cloud infrastructure (GCP/Azure).
• Bonus for startup or regulated industry experience.
• Experience shipping in fast-paced environments.

Responsibilities

• Build fullstack features across AI tax prep, planning, and review products.
• Own the UX and backend logic for the workflows tax professionals use daily.
• Ship fast, monitor metrics, and decide what to improve next.
• Make LLMs work for customers to achieve higher accuracy and transparency.
• Keep the codebase clean, typed, and fast as we scale.

Skills

TypeScript

React

Python

Cloud (GCP/Azure)

Startup experience

Product from 0 to 1

Job description

A Different Kind Of Job Description

At Filed, we believe in radical transparency. Everything is open: company finances, team salaries, stock options, anonymous team feedback. That extends to how we talk about this job, so what you'll read here looks a little different from other job ads. It starts with why this is a terrible job. Then it explains why it might be the best career move you’ll ever make.

A Different Kind Of Job Description

At Filed, we believe in radical transparency. Everything is open: company finances, team salaries, stock options, anonymous team feedback. That extends to how we talk about this job, so what you’ll read here looks a little different from other job ads. It starts with why this is a terrible job. Then it explains why it might be the best career move you’ll ever make.

Why this is a terrible job

This is an incredibly high-paced, high-tempo environment. We're making a generational bet to change all of our lives, and generational bets are not comfortable.

You will build agents for subjective workflows. Tax law is objective, but what applies under it and how professionals interpret it is full of judgment. You can give two tax professionals the same task and get two different results where both are right. We're building agentic systems that have to reach their level of accuracy, not a level we decided is good enough. From an engineering standpoint, this is the hardest thing most of us have ever built. At times it will feel like hitting your head against the wall.

Customers will sometimes get frustrated, because they expect deterministic results from probabilistic systems, and we're managing the expectations of some of the biggest firms in the world, including the Big Four.

And the rhythm is real: we get to the office, we work, we go home and spend time with our families, and then many of us get back online to support our customers in US hours. It's tough. It's relentless.

Why it might be the best career choice you’ll ever make

It's addictive to be part of a business when you know you're winning. Filed is adding millions of dollars of revenue every quarter, customers are signing up in numbers, and in under two years we've become the market leader in a space with entrenched incumbents and a drastic need for new AI tools. When we come into head-to-heads with competitors, we win every time, because our product is superior. And we stay focused and diligent: we only work with tax firms that have the right expectations, which is why our typical customer is mid-market and enterprise.

The industry looks boring from the outside, but the problem is unsolved, and the space has been riddled with products below the mark for decades. When you push through the wall, there's a spark of joy: a customer says "wow, this is phenomenal." That keeps happening.

The opportunity here is not only to make a great deal of money. It's to have real impact on our mission: making this profession extraordinary. Nobody became a tax professional for the admin. They got into this work to be creative with tax law, to have fun, and to change the fabric of society. Filed enables them to do exactly that.

We've raised $17.2 million to date, led by Northzone, and you can read the story in TechCrunch. Our focus now is to deliver the roadmap and continue to win.

What You'll Build

As a Fullstack AI Developer, you'll build the agentic systems at the heart of Filed:

• Agentic workflows that mirror how tax professionals actually work, judgment call by judgment call
• Evaluation and verification systems that measure our accuracy against professional standards, not benchmarks we invented for ourselves
• The model integrations and tooling that turn probabilistic systems into something firms trust with high-stakes work

You'll work at the frontier of applying AI to subjective domains, where two different answers can both be correct, and where shipping means earning the trust of professionals who scrutinize every output.

What You'll Be Responsible For

• Building and maintaining fullstack features across our AI tax prep, planning, and review products
• Owning the UX and backend logic for the workflows tax professionals use every day
• Shipping fast, watching metrics, and deciding what to improve next, without being told
• Making LLMs work for our customers to achieve higher accuracy and transparency
• Keeping the codebase clean, typed, and fast as we scale

Your Hard Skillset

• Comfortable in TypeScript, React, and Python: you've built complex, data-heavy UIs and backend services before
• Familiar with cloud infrastructure on Google Cloud and/or Azure
• Bonus if you've worked in fast-paced startups or regulated industries
• Even bigger bonus if you've taken a product from 0 to 1 and watched real users depend on it

Your Soft Skillset

• Comfortable being uncomfortable and making calls with incomplete data
• Empathetic and curious: building for the user, not just for clean code
• Highly collaborative across product, engineering, and tax
• Detail-oriented but pragmatic: you know when polish matters and when to ship
• You own your work and welcome the accountability that comes with it

A championship team

We think of ourselves as a sports team. Incredibly high performance, incredibly high standards, and real success to show for it. Being a championship team means working with people who are deeply proud of the work they do and have great fun doing it together.

We measure employee happiness constantly, and our eNPS is +60. We don't say that to brag. We say it because a team playing at this tempo only holds together if people genuinely love being on it. Every four months, the whole company comes together for an offsite.

What Filed Stands For

• No problem is someone else's problem If you see it, it's yours. Bugs, customer confusion, missed expectations, internal friction. We don't pass problems sideways and we don't hide behind roles. You fix the typo even if you didn't write it, jump into a customer issue even if it's not your department, elevate early, and close loops fully. Ownership means you drive resolution, not that you suffer silently or burn out doing everything alone.
• Waiting is not a strategy Momentum is our advantage. We don't wait for perfect information or stall because something is unclear. You ship a V1 instead of debating V5, test instead of theorize, run small experiments instead of requesting big approvals, and propose solutions instead of just naming blockers. Speed is powerful. Sloppiness is not, and recklessness has no place in a high-trust industry.
• We run toward the fire When something breaks, we move. Tax is high-stakes and trust is fragile. We acknowledge issues immediately, communicate clearly and often, prioritize customer-impacting problems fast, and stay on it until it's fully resolved. Firefighting is a strength, not panic, and never an excuse for preventable mistakes.
• We win on customer experience AI will commoditize. Features will copy. Pricing will compress. Experience won't. We respond faster than customers expect, communicate proactively, think like a partner rather than a ticketing system, and anticipate needs before they're raised. Overdelivering means raising the standard of care, not overpromising, hero culture, or burning the team out.

Who This Suits

• People who want to win
• People who have a point to prove
• People who want to write their own job descriptions

How We Pay

Nothing at Filed is behind closed doors. Everyone here sees everyone else's salary, because we believe transparency creates trust, and trust is the foundation of excellent teamwork. Compensation isn't a negotiation. Depending on your location, everyone receives the same three offers, and all of our offers are above market benchmarking.

This role is assessed at Level 3 (Mid-Level). The salary and equity bandings are:

• Most Equity: 68,750 SEK per month + $150,000 of equity
• Great Equity: 75,000 SEK per month + $100,000 of equity
• Good Equity: 81,250 SEK per month + $50,000 of equity

We run performance reviews every four months. Meet your goals and you can expect to double your equity by the end of your first year.

One more thing, in the spirit of transparency: some people who apply for this role will be assessed at a different level. If the team determines your level of responsibility sits differently, we'll adjust the offer accordingly. If you know you're suited to a more senior role, don't shrink to fit. Apply to the Senior Fullstack AI Engineer role instead.

Benefits

• A minimum of 30 days of holiday per year, whether you're in Europe or the US
• In the US: fully covered medical expenses on platinum-level plans, with 100% coverage for your dependents as well
• In Europe: the full set of mandatory benefits, and more on top
• Company-wide offsites every four months

The process

• Quick intro call (30 minutes)
• Technical walkthrough and async task (60 minutes)
• Final round with our team (120 minutes)

In just 3.5 hours, you'll be wanting early access, just like the rest of our team, to get into the stack and start building a generational company, even before your first day.

About Filed

Filed is the AI tax preparer trusted by America's accounting firms.

Taxes might seem boring, but they are the $5 trillion backbone of the US economy. Globally, nearly $15 trillion in taxes is collected every year. Behind every dollar of it sits a professional making judgment calls, and the industry that does this work is breaking under a talent shortage no one has solved. We're fixing it. Today, hundreds of firms run Filed inside the systems they already use, and we're backed by Northzone, Neo, Analog, and Raine.

There has never been a more exciting time to work on a problem this complex. Join us while "I was there when it all started" is still true.