C

Full Stack Engineer (onsite SF)

Cadre
Full-time
On-site
San Francisco, California, United States
$150,250 - $150,250 USD yearly

Senior Full-Stack Engineer

Location: San Francisco, CA (In-Person)
Type: Full-Time
Compensation: $150k – $250k + 0.01% – 0.25% Equity
Start Date: Hiring Immediately (7+ roles open)
Visa: Not available

 

About the job

 

Why Alex?

Alex is one of the fastest growing startups to come out of its YC batch with strong traction. We’re generating revenue and are well-funded by some of the best investors in the Valley with years of runway.

 

What are you up to?

Alex is building the future of hiring. Alex is an AI recruiter that conducts job interviews in real-time. Companies use Alex to get the best hiring signal on their applicant pool and hire in a fraction of the time.

Alex has a live conversation over a video/phone call with each candidates based on the interview questions our customers choose or that are recommended based on their job description. During the interview, Alex asks personalized follow-up questions in real-time based on the candidate's responses. Alex has already conducted thousands of interviews across engineering, IT, retail, hospitality, and more.

 

Who are you?

We’re people who:

  • genuinely enjoy solving complex engineering problems
  • learn quickly and do what it takes to deliver results
  • work really, really hard
  • move with urgency
  • enjoy and value working together in person in SF 5 days a week

 

What technologies do you use?

You should have experience in:

  • Javascript (Typescript, React, Node, Next)
  • Python (FastAPI, concurrency)
  • Cloud / DevOps (Azure, Kubernetes, Docker)
  • System Architecture

We also prefer candidates with experience in:

  • Great frontend design (Figma)
  • ML/DL (open source, inference at scale)

 

What can I work on?

Our product is built and operates like a marketplace, as we serve both candidates through the interview experience and employers through the data aggregation and analysis platform. As a hands-on engineer, you will build both consumer-facing and enterprise-grade software, designed for scale.

 

Problems that you could work on related to consumer software are:

  • How can we bring the average interviewer response latency down to 200ms?
  • How can we fine-tune our models to decrease hallucination and increase response accuracy?
  • How will our system architecture change as we scale to thousands more users, concurrently?

Problems that you could work on related to enterprise software are:

  • How do we integrate with our customer’s internal hiring systems?
  • What’s the best way to present the interview data visually and as fast as possible?
  • And many, many feature requests that need to be built out!

 

What’s in it for me?

  • Take ownership of building the next billion dollar company
  • Collaborate with a tight-knit team of talented builders
  • Launch products that directly impact people’s careers
  • Work with the co-founders every day in-person in SF
  • Competitive salary and equity
  • Health/vision/dental insurance, 401(k), unlimited PTO, and great company events

 

If you’ve gotten this far and our culture/tech resonate with you, we want you to apply. Submit your application with the phrase “fast track” and we’ll fast track your application with an interview directly.

🛠️ What You’ll Work On

As a hands-on engineer, you'll help us design and build the systems that power both sides of this marketplace. Your work will touch everything from real-time AI infrastructure to scalable backend integrations and intuitive frontends.

💡 Consumer-Facing Engineering Challenges

  • Bring AI interviewer response latency under 200ms

  • Scale infrastructure to handle 1,000+ concurrent interviews, globally and compliantly

  • Build and maintain a vector database for matching candidates on complex traits

🏢 Enterprise-Facing Engineering Challenges

  • Integrate with customer ATS and internal hiring systems

  • Build blazing-fast visualizations of interview data

  • Ship countless new feature requests from our growing customer base

🎯 Responsibilities

  • Build and own full-stack products across consumer and enterprise platforms

  • Optimize performance across frontend, backend, and AI interfaces

  • Scale system architecture and infrastructure (Azure, Kubernetes, Docker)

  • Integrate third-party systems and APIs with precision and stability

  • Visualize complex interview data clearly and efficiently

  • Collaborate cross-functionally with co-founders and the broader team

  • Launch impactful features fast—weekly, not quarterly

  • Work in-person with an ambitious team based in SF

🧠 Ideal Candidate Profile

Experience

  • 5+ years of full-stack engineering experience (staff, senior, or principal level)

  • Built production systems with React (TypeScript) and Python (FastAPI, asyncio)

  • Experience at a fast-growing startup for 2+ years

  • Strong understanding of vector databases, embeddings, or semantic search

  • Familiar with DevOps and Cloud Infra (Azure, Docker, Kubernetes)

  • Solid grasp of PostgreSQL and data modeling

  • Degree in CS / Math / Engineering from a top-tier university

Skills & Traits

  • Strong frontend design sense; can bring Figma designs to life

  • Operates with ownership, urgency, and pragmatism

  • Excited by ambiguity and end-to-end product development

  • Willing and eager to work in-person 5 days/week in San Francisco

📌 Interview Process Tips

We’ll ask things like:

  • Have you built a full-stack app in React? Did it have its own backend?

  • Can you relocate to SF, or are you already here?

  • What are your salary expectations and current recruiting activity?

🔧 Tech Stack

  • Frontend: React (TypeScript)

  • Backend: Python (FastAPI, asyncio)

  • Infra: Azure, Kubernetes, Docker

  • Database: Postgres, Vector Databases

  • Design: Figma

 

Apply now
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