Backend Engineer (NodeJs)

Top 3 reasons to join us

• Competitive salary packages.
• Dynamic and open-sharing working environment.
• Hybrid and flexible working mode.

Job description

Build like a founder. Ship like Spartan.

Our customers are scaling fast — and so are we. That’s why we’re looking for a Backend Engineer
to join our world-class team.

At Spartan, we don’t act like vendors. We embed with startups backed by
YC, Pear VC, BlingCap ,a16z, Techstars, and more — partnering with founders and engineers from
Stanford, MIT, Yale, Google, Amazon, Uber, and beyond.
Together, we help launch MVPs in 30 days and scale systems that power billions of requests.

This isn’t “just another backend role.” It’s a chance to work shoulder-to-shoulder with elite builders, solve complex startup challenges, and see your code directly drive companies raising millions on the global stage.

You’ll also be working at the frontier of AI:
70% of our portfolio today is LLM-powered. Our engineers leverage the latest tools like
Cursor, Claude, and Codex
to move faster, write cleaner code, and solve harder problems.
 

Key Responsibilities

• Design, develop, and maintain backend services using Node.js
• Build and optimize RESTful APIs (and potentially GraphQL)
• Collaborate with frontend engineers, product managers, and cross-functional teams
• Implement best practices in coding, testing, and deployment
• Ensure system scalability, security, and performance
• Participate in code reviews, technical discussions, and architectural planning

Your skills and experience

Requirements: 

• Fluent in English
  — you’ll talk directly with US startup founders.
• 4+ years of experience in backend development
• Strong proficiency in Node.js, Express.js (or similar frameworks)
• Solid knowledge of databases (SQL and/or NoSQL)
• Familiarity with cloud platforms (AWS, GCP, or Azure)
• Understanding of CI/CD pipelines, version control (Git), and testing frameworks
• Strong CS fundamentals: algorithms, data structures, scalability.
• Experience with testing, dependency injection, and distributed systems.
• A builder’s mindset — you don’t just code, you solve problems like an owner

Tech We Use

• NodeJs • Go • Java/Kotlin/Scala • TypeScript • Python • 
• Postgres • MongoDB • DynamoDB • ElasticSearch • Redis
• Pinecone • Qdrant • pgvector
• Kafka • Pulsar • SQS • AWS Kinesis • GCP Cloud Tasks
• AWS • GCP • Azure • Kubernetes (k8s)
• Spark • Flink
• Jenkins • GitHub Actions
• DataDog • Prometheus • Grafana • ELK Stack (Elasticsearch, Logstash, Kibana)

Why you'll love working here

Perks & Benefits

• 💰Competitive salary
• 🏝Unlimited PTO+ public holidays
• 🩺 Premium healthcare insurance
• 🏃 Sports coverage (Strava integration)
• 🏠 Hybrid working style
• ✈️ Annual company trip + monthly team parties

Career Growth

• Work with
  founders from Stanford, MIT, Yale, Google, Amazon, Uber, and more.
• Exposure to
  cutting-edge tech
  (LLMs, AI agents, cloud infra, real-time systems).
• Transparent career path and mentorship from engineers who’ve taken 3 companies to IPO.
• Solve real startup challenges— every project feels like its own mini-startup.

Why Spartan

• 50+ MVPs launched, 3 IPOs, $100M+ raised.
• 95% engineer retention — because we hire the top 1%.
• You’ll never just “take tickets” here. You’ll
  own problems, ship fast, and grow with the founders we partner with.