---
title: 'Staff/Senior Software Engineer at Swift Solar'
canonical: 'https://feeny.ai/job/staff-senior-software-engineer-swift-solar-san-carlos-2yvj4qx74q94'
type: 'job'
last_seen: '2026-11-06'
---

# Staff/Senior Software Engineer at Swift Solar

- **Company:** Swift Solar
- **Location:** San Carlos, CA
- **Posted:** 2026-10-09
- **Last confirmed live:** 2026-11-06
- **Apply:** https://job-boards.greenhouse.io/swiftsolar/jobs/5441242008

## Job description

## About the company

At Swift Solar, our mission is to unlock the full potential of solar energy. We believe solar can provide affordable, reliable, resilient, clean energy to virtually anyone, anywhere. But while today’s solar technology is good, it’s not good enough.

Swift Solar’s breakthrough perovskite-silicon tandem technology will drive solar power to commanding new heights. Our tandem cells stack a perovskite layer on top of a heterojunction (HJT) silicon cell, delivering dramatically higher efficiency than traditional silicon alone. In 2026, we acquired Meyer Burger’s HJT intellectual property and manufacturing assets, giving us the world’s most extensive HJT patent portfolio and a clear path to gigawatt-scale domestic production.

This vertically integrated approach means we can design, manufacture, and scale next-generation solar solutions entirely in the United States—from silicon foundations to perovskite innovations. Our technology enables applications ranging from space solar to utility-scale power generation, creating American-made solutions for a world facing growing energy challenges.

Swift Solar is on a journey to bring revolutionary clean-energy technology to market. We’re in it for the long haul, with support from world-class investors. Join our extraordinary team building the cutting-edge solar technology that will power the future.

A day in the life

You'll build AI products that assist scientists and accelerate our technical progress towards next-generation solar solutions. Every experiment we run costs tool time, materials, and scientists' attention, so choosing what to run next is one of the biggest levers on how fast our cells improve. You'll build the AI that helps our scientists make those choices. Our systems read scientific literature and query our lab and manufacturing data, then propose experiment plans that an automated optimizer uses to execute them.  You will lead development of the planning and reasoning layer, which takes a research objective as input and uses a multi-agent system to guide our scientists and reach goals faster through the best selected experiment campaigns. Additionally, we need to measure what works and how frontier models and our own agents perform on problems our team has already worked through, so we can improve the system over time.

This is also a place to experiment. When a promising new paper, model, or agent design comes out in AI for science, you can try it here on real problems instead of benchmarks someone else chose. You'll work with scientists who have spent years on perovskites, who know which questions matter and can tell you quickly whether an agent's answer makes sense. Because we develop the process and make the devices ourselves, the data, tools, and people who understand them live in the same company, so an idea can go from your screen to a measured result without waiting on anyone outside.

Most of this is greenfield work, and speed matters. You'll get rough versions in front of scientists quickly, watch how they use them, and turn the ideas that hold up into production systems people rely on every day. Knowing when a prototype is ready to harden, and doing it without losing momentum, is a big part of the job.

Alongside the agent work, you will:

- Hold AI-written code to a high bar. Nearly all of our code is written with AI coding tools, so critically reviewing the output and keeping the codebase documented and tested matters.
- Help keep our existing data systems running, including the pipeline that brings instrument data into our database.
- Review code across the team, and help hire and mentor new engineers as the team grows.
- Write about what we learn for our public whitepaper series and, when the work holds up, publish it in papers and present it at conferences.

You might be a good fit if you...

- Have 5+ years of professional software engineering experience, including systems that real users depend on
- Have built full-stack web applications, with a Python backend and a TypeScript/JavaScript frontend (React, Vue, Svelte, or similar)
- Have built applications on frontier LLMs through their APIs, such as agents, multi-step orchestration (e.g., LangGraph), or systems where models call tools
- Can take an idea from a quick prototype to a production system that people depend on
- Use AI coding tools like Claude Code every day, and can tell when what they produce is wrong
- Have a CS degree or a comparable record of open-source or portfolio work
- Write documented, tested code and are comfortable working in a shared codebase with git
- Can explain technical tradeoffs to scientists who aren't software engineers
- Take initiative and work independently
- Are coachable and comfortable when priorities change quickly
- Are kind, empathetic, conscientious, and motivated to make an impact on climate change

A strong candidate might bring one or more of the following...

- Experience with multi-agent systems, especially ranking, review, or memory between runs
- Experience building evaluations or benchmarks for LLM agents
- Experience designing complex software architecture and leading projects end-to-end without much oversight
- Familiarity with Bayesian optimization, surrogate models, fine-tuning of open-weights models, or reinforcement-learning environments
- Experience analyzing and plotting scientific data
- An interest in science, shown through conferences, side projects, or papers (a science background is not required)
- Experience getting skeptical users to adopt internal tools
- Experience with SQL or database administration, AWS, Azure, or GCP, or CI/CD
- Experience working at a startup

The logistics

- Compensation: Competitive package including salary, equity, and benefits
- Expected Pay Range: $150,000 - $220,000 per year
- The actual offer, reflecting total compensation and benefits, will be determined by factors such as relevant experience, skills, and other qualifications
- Ideal start date: November - December 2026
- Job type: Full-time
- Location: San Carlos, CA (Swift Solar HQ), with some remote days possible

## What you’ll love about Swift

- Work with purpose: Join our mission to unlock the full potential of solar energy and make a global impact.
- Lead with innovation: Be part of an extraordinary team building cutting-edge solar technology - growth mindset; culture
- Thrive with benefits: Have 100% of your monthly premiums for HMO / PPO group healthcare plan options and 75% of your dental and vision insurance premiums covered by us. Employees also benefit from 401(k) matching, clean commuter benefits, and meaningful equity.
- Invest in your career: You’ll grow your skills, your network, and your perspective at Swift. We’ll support you in attending conferences and taking online courses, as long as you share your new insights with the team.

We recognize that candidates from underrepresented backgrounds often hesitate to apply if they don’t meet all the criteria. If you’re excited about this role and believe you can contribute to our team, we encourage you to apply—even if you don’t meet every qualification listed. We're eager to meet people from all backgrounds, and your unique skills and experiences could be exactly what we need.

If you believe in our mission but this isn’t the right job for you, please explore other career opportunities on our website and email us at careers@swiftsolar.com with any questions. If you have a friend who would be a perfect fit, share this link with them. Thanks!

Swift is an equal opportunity employer. We value an inclusive work environment and welcome team members of all backgrounds and perspectives.

## About Swift Solar

## Company Overview
- **One-liner**: Swift Solar is a US solar technology company developing high-efficiency, lightweight perovskite tandem solar panels for applications ranging from space to utility-scale energy.
- **Entity Type**: Private (Series A)
- **Headquarters**: San Carlos, California, United States
- **Founded**: 2017
- **Founders**: Joel Jean (CEO), Tomas Leijtens (CTO), Giles Eperon (Chief Scientific Officer), Max Hoerantner (Chief Engineer)

## Core Business
- **Primary industry**: Solar energy / Perovskite photovoltaic manufacturing
- **Target customers**: B2B — data centers, vehicle manufacturers (EVs), space/satellite operators, utility-scale solar developers, and commercial/industrial solar installers
- **Mission**: Unlock the full potential of solar energy

## Products & Services
- **Perovskite Tandem Solar Panels**: Ultra-efficient, lightweight solar modules that combine perovskite and silicon materials to exceed traditional silicon cell efficiency. Applications include:
  - **Utility-scale solar**: Smaller arrays with shorter payback periods
  - **Commercial & industrial solar**: Cost-effective, high-efficiency rooftop and ground-mount systems
  - **Residential & community solar**: Smaller arrays with faster payback
  - **Vehicles**: Integrated solar for EVs, gaining tens of miles of range per day
  - **Space solar**: High-efficiency, radiation-tolerant panels for satellites and spacecraft
  - **Data centers**: High-efficiency on-site power generation

## Market Standing
- **Valuation**: Not publicly disclosed
- **Key Metric**: Total Funding — **$50.4M** across 6 rounds
- **Notable Investors/Partners**: Eni Next (lead, Series A), Fontinalis Partners (lead, Series A), Sytse Sijbrandij (lead, Seed), Safar Partners (lead, Seed), National Science Foundation (Grant)
- **Growth Signals**: 
  - Headcount of 41 employees (+34.7% YoY, +17.9% monthly growth)
  - Named one of TIME’s Top GreenTech Companies in America
  - Won R&D 100 Award
  - 10 active job postings (+400% quarterly growth in postings)
  - LinkedIn followers: 10,657 (+38.3% yearly growth)

## Competitive Advantages
- **Proprietary perovskite tandem technology**: Combines perovskite and silicon to exceed the efficiency limits of traditional silicon-only solar cells
- **Patent-protected materials, architectures, and manufacturing methods** built on over a decade of foundational research by the founding team
- **US-based manufacturing focus**: Positioned to benefit from domestic clean energy incentives (IRA) and supply chain resilience
- **World-class founding team**: Spun out of Stanford, MIT, and NREL; founders are leading perovskite scientists with multiple Clarivate Highly Cited Researcher and Forbes 30 Under 30 recognitions
- **Proven stability and scalability**: Claims 30-year equivalent lifetime, with full-size cell efficiency within 10% of lab records

## Strategic Focus
- Scaling US-based manufacturing of perovskite tandem solar panels
- Expanding into multiple high-value verticals: space, automotive, data centers, and utility-scale
- Continuing R&D to improve efficiency, stability, and manufacturability
- Building out a world-class manufacturing and engineering team in San Carlos, CA

## Why Work Here
- **Mission-driven work**: Directly contribute to unlocking the next generation of solar energy and combating climate change
- **Cutting-edge technology**: Work on perovskite tandem solar cells — one of the most promising emerging solar technologies
- **Strong growth trajectory**: Rapidly scaling headcount (+34.7% YoY) with significant new funding and active hiring across engineering, R&D, and manufacturing roles
- **Benefits**: Full health benefits, 401(k) matching, meaningful equity, and growth opportunities
- **Location**: San Carlos, CA (Bay Area) — on-site roles with a collaborative lab and manufacturing environment
- **Culture**: Described as a global team of innovators, technologists, and manufacturing experts working with purpose

## Sources
1. [swiftsolar.com](https://www.swiftsolar.com/)
2. [swiftsolar.com/about](https://www.swiftsolar.com/about)
3. [swiftsolar.com/careers](https://www.swiftsolar.com/careers)
4. [linkedin.com/company/swift-solar](https://www.linkedin.com/company/swift-solar)
5. [cbinsights.com/company/swift-solar](https://www.cbinsights.com/company/swift-solar)

## Other roles at Swift Solar

- [Mechanical Design Engineer](https://feeny.ai/job/mechanical-design-engineer-swift-solar-san-carlos-rszgpj1x09v3) — San Carlos, CA
- [Supply Chain Engineer](https://feeny.ai/job/supply-chain-engineer-swift-solar-san-carlos-x4zca0p5ds7m) — San Carlos, CA
- [Process Technician](https://feeny.ai/job/process-technician-swift-solar-san-carlos-m55pteprvcdx) — San Carlos, CA
- [Future Opportunities at Swift Solar](https://feeny.ai/job/future-opportunities-at-swift-solar-swift-solar-san-carlos-nky9wdgzhws3) — San Carlos, CA