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Y Combinator

Seed-stage startup accelerator and investor

Investment Associate & Product Engineer

Full-TimeUpdated on 10/23/2026
$250k - $500k+ Profit-sharing
Mid
United States
In PersonBased in the San Francisco Bay Area or willing to relocate.
Software EngineeringFull-Stack Engineering
H1B Sponsorship Available

About the job

Requirements
  • Experience shipping full-stack web applications.
  • Ability to design systems and reason about tradeoffs independently.
  • Strong analytical thinking and comfort with metrics and financial concepts.
  • Clear written and verbal communication.
  • Excellent judgment, integrity, and ability to work with sensitive information.
Responsibilities
  • Design, build, and ship full-stack web applications for partners, founders, and investors.
  • Own features end-to-end, including scoping, design, implementation, and iteration.
  • Work across frontend, backend, and data layers to improve post-batch and internal platforms, including founder tools, analytics, and workflow systems.
  • Make pragmatic engineering tradeoffs in a fast-moving, high-ownership environment.
  • Evaluate post-batch and growth-stage companies by analyzing business models, markets, teams, and operating metrics.
  • Contribute to diligence efforts, including reviewing decks and data rooms, benchmarking key performance indicators, and conducting market or customer research.
  • Build and maintain analytical tools, dashboards, or workflows that support investment decisions.
  • Write clear, structured memos and analyses for partners and the Investment Committee.
  • Work closely with partners and founders to build products and systems.
Desired Qualifications
  • Experience with Ruby on Rails, React, Postgres, or similar frameworks and databases.
  • Prior experience in venture capital, growth equity, banking, consulting, or corporate development.
  • Founder or early-stage startup experience.
  • Experience building internal tools, analytics platforms, or workflow software.

About the company

Y Combinator is a startup accelerator that funds early-stage companies through seed investments and a three-month, batch-based program. Founders receive mentorship, guidance on product and business strategy, and a Demo Day to present to invited investors. The program runs four times a year, creating a strong network effect among participants who can support one another and share experiences. The accelerator’s portfolio spans software, fintech, biotech, and consumer products, with notable alumni including Stripe, Airbnb, and Coinbase. Unlike many investors, Y Combinator combines a small equity stake with access to a vast alumni and investor network, monetizing returns from successful exits such as acquisitions or IPOs. Its goal is to identify high-potential ventures, help them grow, and generate meaningful financial returns for its stakeholders through exits.

Company Size

1,001-5,000

Company Stage

Pre-seed

Total Funding

$51B

Headquarters

San Francisco, California

Founded

2005

Get referred to Y Combinator

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Simplify Jobs

Simplify's Take

What believers are saying

  • Startup School 2026 drew over 6,000 builders to Chase Center in July.
  • YC restored Canada as an accepted incorporation country on February 5, 2026.
  • The YC AI Stack offered over $25,000 in credits to attract AI founders.

What critics are saying

  • Delve parted ways with YC on April 4, 2026 after compliance allegations.
  • Parker filed Chapter 7 on May 7, 2026 after a collapsed $90 million sale.
  • Repeated startup blowups push founders toward direct AI capital, weakening YC’s core moat.

What makes Y Combinator unique

  • June 2026 added Diana Hu, Christopher Golda, Grey Baker, and Harshita Arora.
  • YC’s 2026 Demo Days and Startup School 2026 still command founder-investor attention.
  • Launch YC and the Startup Directory make YC’s sourcing and discovery durable.

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Benefits

  • Health Insurance
  • Dental Insurance
  • Vision Insurance
  • Life Insurance
  • Disability Insurance
  • Health Savings Account/Flexible Spending Account
  • Unlimited Paid Time Off
  • Paid Holidays
  • 401(k) Retirement Plan
  • 401(k) Company Match
  • Parental Leave
  • Fertility Treatment Support

Company News

PR Newswire
Oct 22nd, 2026
Tractian raises $130M Series D at $1.4B valuation to scale Physical AI for industry

Tractian, an Atlanta-based Physical AI platform for asset-heavy industries, has raised a $130 million Series D at a $1.4 billion valuation. Sapphire Ventures led the round, co-led by MG's Catalyst. N47, General Catalyst, Bosch Ventures, 53 Stations, Monashees, Endeavor Catalyst, Norte Ventures, and Y Combinator also took part. Tractian uses vibration, ultrasound, and other sensors to track machine condition. Its AI, trained on one of the largest industrial failure datasets, diagnoses root causes and recommends actions. More than 2,000 facilities use it, including customers such as Eli Lilly, Whirlpool, and Coca-Cola. Chief executive officer Igor Marinelli said the money will help scale the platform and cut unplanned downtime. Siemens data cited in the release puts that cost at about $1.4 trillion a year for the world's 500 largest industrial companies.

Ain.ua
Oct 21st, 2026
Freya raises $3.5M seed round to automate business conversations

Freya announces a $3.5 million seed round, with participation from Y Combinator, Rebel Fund, 212 VC, N1 Tech, BD Partners, and several angel investors. - AIN

Tech Funding News
Oct 21st, 2026
Firstwork raises $15M to cut frontline hiring drop-off with AI agents

Firstwork, a Y Combinator alumnus, has raised $15 million in a Series A round led by Earlybird Venture Capital, bringing its total funding to $20 million. Legion VC, Deel Ventures, Gradient, and Y Combinator joined the round, as did SOMA Capital, 468 Capital, and Houghton Street Ventures. The startup uses AI agents to cover the gap between a job offer and a first shift, when many frontline hires drop out. The agents text or call candidates, chase missing documents, arrange training, and follow up after shifts. They work with existing HR, payroll, and screening software. Founder Vardhan Kapoor, a former Deliveroo head of strategy and operations, started the company in 2024. Firstwork has about 45 employees and is setting up a London headquarters to serve European clients.

The SaaS News
Oct 21st, 2026
Pennant raises $5M seed to build AI-native proxy voting platform

Pennant, a corporate governance technology company, has raised $5 million in a seed round to build an AI-native platform for proxy voting and shareholder engagement. Y Combinator backed the round. The company will use the money to build a world model for corporate governance. It aims to improve its platform for proxy voting and institutional research. Founded by Ryan Nowicki Stewart and Tomas Taylor, Pennant links institutional research, voting policies, and past decisions to help investors exercise independent judgment. Its clients include pension funds and asset managers.

The Paypers
Oct 20th, 2026
Rebill raises $5.4M pre-Series A to expand payments infrastructure across the Americas

Rebill, an Argentina-based payment infrastructure company, has closed a $5.4 million pre-Series A round. Total funding since its 2020 founding now exceeds $9 million. The round includes a renewed investment from the founder and chief executive officer of Vercel, and a SpaceX executive investing personally. Existing backers include Tiger Global, Y Combinator, SV Angel, Soma Capital, and a Dropbox co-founder. Rebill lets merchants collect payments across borders as a local business would, without setting up a local entity. It operates in Argentina, Brazil, Chile, Colombia, Mexico, and the US, and counts Henry, Assist 365, and TripleTen as clients. The money will fund growth in current markets, deeper US operations, and two new lines: Rebill Treasury, for managing multi-currency funds, and Rebill Platforms, which lets software platforms offer payments under their own brand.