CrawlJobs Logo
0x Logo 0x · IT - Software Development

Senior Backend Engineer API

United States 95000.00 - 230000.00 USD / Year · Job Posted January 05, 2026
Apply Position
Job Link Share

Job Description

At 0x, our mission is to 'Create a Tokenized World Where All Forms of Value Can Flow Freely'. We deliver this to web3 builders with a delightfully simple suite of developer APIs that provide faster trading, better prices, and superior user experience. Matcha is a DEX aggregator, built by 0x. With over 5 million tokens indexed across 9 blockchains, the decentralized exchange provides aggregated liquidity from +100 sources and the most efficient trade execution through smart routing. Matcha offers swaps, limit orders and cross chain trades, having enabled over $62B volume and 3.5M+ trades as the first consumer-facing product by the 0x team. 0x platform is developers' one-stop shop to build financial products on crypto rails. 0x empowers hundreds of teams and developers with essential web3 tools to enable faster trading, better prices and superior UX.

Job Responsibility

  • Be an individual contributor on projects as well as lead technical projects of moderate to high complexity
  • Offer valuable insights as a peer when reviewing designs and performing code reviews
  • Create high quality, secure, clean code
  • Improve the way we build and deliver software
  • Consistently ship
  • Coach and mentor other engineers and generally up-level the team
  • Empathize with our customers and users

Requirements

  • 7+ years of experience solving complex distributed computing problems
  • Fluent in TypeScript/JavaScript - you can confidently write and debug APIs in Node/Express without relying on type-casting hacks or constant lookup
  • Experienced with designing and building systems that include: Relational or Key-Value datastores
  • Distributed, event-driven architectures (Kafka, queues, streams)
  • Cloud-based deployment (preferably AWS)
  • External-facing REST/HTTP APIs
  • Monitoring dashboards (preferably Grafana)
  • Strong problem-solving and debugging skills - you can isolate issues, reason through errors, and explain your approach clearly
  • Up to date on emerging trends in modern backend technology solutions (databases, queues, caching, etc.)
  • Passionate about DeFi and how it can improve people’s lives. You’ve used DeFi apps yourself and care about building better ones

Nice to have

  • Experience working with search engines (ElasticSearch, OpenSearch)
  • Solid understanding of blockchains (especially EVM chains). You know fundamentals like chain IDs (e.g., Ethereum mainnet = 1, Polygon = 137) and how replay protection works
  • Experience working with JSON-RPC APIs to interact with blockchain nodes for tasks like querying data, sending transactions, or monitoring events
  • Experience with Web3 libraries (e.g., ethers.js, viem, Web3.js) to build/test blockchain integrations

What we offer

  • Comprehensive insurance (medical/dental/vision/life/disability) for U.S.-based employees — 100% of base plan covered for you and dependents
  • 401k and FSA for U.S.-based employees
  • Monthly mobile phone bill, wellness, and pre-tax transportation expense
  • Covered mental health benefits (included professional therapy sessions)
  • A supportive remote environment
  • Lunch reimbursement for all employees across the globe!
  • Stipend for your ideal remote / WFH set-up: headphones, and any other work gear you may need
  • 12-week paid parental leave
  • Great office conveniently located in the SF Financial District for those in the region!
  • Flexible vacation: Take time when you need it (and we really mean it!)
0x - All Job Offers

Looking for more opportunities?

Search for other job offers that match your skills and interests.

Suggested Tags: Frontend Developer Secretary Talent Manager Salesforce Administrator Data Analyst
Similar Jobs for

Senior Backend Engineer API

8 matching positions

Senior Backend Engineer (Platform and API)

We're looking for a senior backend engineer to join the Channels and Platform te...
Location
Location
Salary
Salary:
156500.00 - 202300.00 USD / Year
buffer.com Logo
Buffer
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • You have practical experience designing, implementing, and maintaining public APIs, plug-in ecosystems, or extensibility platforms
  • You have deep experience with modern stack — we use Node.js, TypeScript, GraphQL, and MongoDB
  • You’ve led backend projects from start to finish — shaping architecture, guiding trade-offs, and delivering reliable systems that support real-world product needs
  • You have strong systems thinking. You look beyond the immediate task, anticipate downstream effects, and help teams converge on architecture that supports the long game
  • You’ve worked across teams to drive platform or infrastructure improvements — whether simplifying service boundaries, improving observability, or evolving internal tooling
  • You’ve contributed to collaborative or multi-user product features, and you understand the data, consistency, and UX considerations that come with them
  • You’re fluent with modern AI tools — not just using them for code generation, but integrating them into how you debug, document, explore ideas, and reduce manual effort
  • You care about performance, scale, and clean abstractions — and know how to measure, prioritize, and improve them pragmatically
  • You’ve influenced engineering culture through code reviews, mentoring, or leading by example, and you’re comfortable being a resource for others on architectural decisions
  • You have a personal stake in the world of content creation
Job Responsibility
Job Responsibility
  • Be part of a small, dedicated squad within the Channels and Platform team responsible for Public API development
  • Lead the development of the backend systems for the Buffer Platform. This includes creating an API for core Buffer features, internal services to ensure Public API stability, availability, high performance, and developer tools for platform clients
  • Improve and evolve our internal systems — helping consolidate services into a monorepo, improve tooling and observability, and reduce complexity across the board
  • Collaborate closely with engineers, product, and design to scope work, explore trade-offs, and find the simplest path to something great
  • Make steady improvements to performance, reliability, and data modeling, helping us scale quality over time
  • Participate in on-call rotation (all engineers take on a 24/7 week-long shift once a quarter on average) and day-to-day maintenance work required to keep the lights on the systems owned by the team (this includes bug fixing, addressing security vulnerabilities, incident follow-ups, etc.)
  • Contribute to shaping our engineering culture by sharing knowledge, reviewing code, and leading by example
What we offer
What we offer
  • Competitive salary
  • Work remotely
  • 4-Day workweeks
  • Health insurance
  • Home office setup
  • Growth mindset fund
  • New laptop
  • Unlimited free books
  • AI tools stipend
  • Flexible time off
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer

Lead the development of innovative solutions and contribute to a meaningful miss...
Location
Location
Japan , Tokyo 23 wards
Salary
Salary:
10000000.00 - 16000000.00 JPY / Year
https://www.randstad.com Logo
Randstad
Expiration Date
July 15, 2026
Flip Icon
Requirements
Requirements
  • 8+ years of experience in backend software development
  • Expert knowledge of at least one major backend programming language (e.g., Java, Python, Go)
  • Experience with relational and NoSQL databases
  • Experience with cloud platforms (e.g., AWS, Google Cloud, Azure)
  • Strong understanding of software design principles and patterns
  • Excellent problem-solving and analytical skills
  • Experience working in an agile environment
  • Experience with containerization technologies (e.g., Docker, Kubernetes)
  • Experience with CI/CD pipelines
Job Responsibility
Job Responsibility
  • Lead the design and implementation of new features and functionalities for our backend systems
  • Develop and maintain high-quality, scalable, and maintainable code
  • Collaborate with other engineers to design and implement APIs and integrations
  • Write unit and integration tests to ensure code quality
  • Participate in code reviews and provide constructive feedback
  • Troubleshoot and resolve production issues
  • Contribute to the overall architecture and design of our backend systems
  • Stay up-to-date with the latest technologies and trends in backend development
What we offer
What we offer
  • 健康保険
  • 厚生年金保険
  • 雇用保険
  • 労災保険
  • 通勤費 (1ヶ月50,000円を上限として全額支給)
  • 完全週休2日制（土日祝）
  • 年間休日：120日
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer - Threat Intelligence

As a Senior Backend Engineer in the Threat Intelligence team, you will own the f...
Location
Location
Czechia , Prague
Salary
Salary:
Not provided
rapid7.com Logo
Rapid7
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • A minimum of 5 years of software development experience in a production environment with deep proficiency in Backend technologies (Python), including API design, Databases, and Microservices, alongside solid experience with modern Frontend frameworks
  • Experience with Cloud computing (e.g., GCP, AWS, or similar)
  • Experience with DevOps practices (CI/CD pipelines, etc.)
  • Problem Solving: Strong creative problem-solving skills with a focus on system design and performance optimization
  • Attention to Detail: Excellent attention to detail and a commitment to high-quality technical execution
  • AI Proficiency: Hands-on approach to AI Research and the ability to integrate AI into production environments
  • Passionate and responsible team player with strong communication skills
  • You aren't afraid to challenge the status quo, bringing innovative thinking and a fresh perspective to complex problems
  • Understanding of the full lifecycle development process, including business and functional requirements, developing technical designs, implementation of scalable solutions, and object-oriented design
  • You are an active driver of change. You thrive in high-growth environments and are eager to lead the team through technical shifts
Job Responsibility
Job Responsibility
  • Build, maintain, and release well-architected services by writing clean Python code and following best practices
  • Own a feature from database design to the UI, making well-reasoned design tradeoffs
  • Lead AI Research & POCs to find innovative solutions for threat intelligence
  • Take an active role in high-level architectural thinking, working with both legacy code and greenfield projects
  • Partner with internal teams to ensure we are understanding and delighting our customers
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer

My client is a well funded early stage startup building a high scale social plat...
Location
Location
United States , New York
Salary
Salary:
150000.00 - 300000.00 USD / Year
apollo-solutions.com Logo
Apollo Solutions
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • Strong expertise in TypeScript, Node.js, and NestJS, with the ability to design and build production grade backend systems
  • Proven experience implementing secure authentication systems using OAuth, FIDO2 or WebAuthn, and JWT
  • Hands on experience working with Prisma ORM, PostgreSQL or Aurora, Redis, and DynamoDB across high-scale environments
  • Strong understanding of distributed systems, including event driven architecture, pub sub patterns, and message brokers such as Kafka or AWS MSK
  • Experience building real time systems
  • Deep familiarity with AWS and cloud infrastructure, including services such as Aurora Global Database, RDS Proxy, ElastiCache or Valkey, EKS, and Terraform
  • Experience working with observability tooling such as LGTM stack and implementing modern CI/ CD pipelines
  • Proven track record of building external facing systems where performance, concurrency, and reliability are critical
Job Responsibility
Job Responsibility
  • Design, build, and deploy backend services using TypeScript and NestJS with a focus on performance, scalability, and maintainability
  • Architect and implement high traffic APIs, authentication systems, and distributed services enabling real-time and AI-enhanced product features
  • Model and optimize data systems across relational databases, caches, and event streaming platforms to support both operational workloads and AI-driven insights
  • Build resilient, event-driven systems using pub sub patterns and long-lived connections that handle large scale concurrent usage
  • Work closely with AWS infrastructure to improve deployment pipelines, scalability, and overall system reliability
  • Support backend systems that enable AI and machine learning workflows, including data pipelines and real-time inference services
  • Collaborate with a small, high-performing engineering team to make strong technical decisions and execute quickly with high ownership
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer

The Senior Backend Engineer will design and build scalable, production-grade sys...
Location
Location
United States , Glendale
Salary
Salary:
160000.00 - 180000.00 USD / Year
https://www.roberthalf.com Logo
Robert Half
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • 5–8+ years of backend or full-stack software engineering experience
  • Strong proficiency in Node.js, Python, Go, or similar backend languages
  • Experience building and maintaining RESTful and/or GraphQL APIs
  • Hands-on experience with event-driven architectures (e.g., Kafka, RabbitMQ, SQS)
  • Strong understanding of microservices design and distributed systems
  • Experience working with cloud platforms (e.g., AWS) and modern deployment practices
  • Strong knowledge of relational and NoSQL databases and data modeling
  • Demonstrated ability to build scalable, production-grade systems
Job Responsibility
Job Responsibility
  • Design, develop, and maintain scalable backend services and APIs that power core business functionality
  • Build and operate event-driven, distributed systems supporting high-throughput data processing
  • Develop RESTful and/or GraphQL APIs for real-time data access and system integration
  • Integrate backend systems with AI/ML models, data pipelines, and workflow automation systems
  • Architect microservices and ensure systems are reliable, observable, and performant at scale
  • Implement and optimize data pipelines for ingestion, transformation, and delivery
  • Collaborate with cross-functional teams to translate system design into working solutions
  • Lead technical discussions, contribute to architecture decisions, and guide system design best practices
  • Mentor engineers through code reviews, knowledge sharing, and technical leadership
  • Identify and resolve performance bottlenecks, system issues, and technical debt
What we offer
What we offer
  • Comprehensive medical coverage with high employer contribution
  • Retirement savings plan
  • Generous paid time off policy
  • Additional employee perks including wellness initiatives and team-provided meals
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer (AI Focus)

Location
Location
Spain; Bosnia & Herzegovina; France; Italy; Kosovo; Malta; Moldova; Portugal; Romania; Serbia; UK; Ukraine
Salary
Salary:
Not provided
deel.com Logo
Deel
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • 8+ years of experience in backend/full-stack engineering
  • JavaScript, Node.js and PostgreSQL experience
  • Strong API integration skills
  • Hands-on experience integrating AI APIs into production systems
  • Comfort working with unstructured/messy data and ETL pipelines
Job Responsibility
Job Responsibility
  • Build backend services that bring AI capabilities to life inside our Payroll workflows
  • Collaborate with ML engineers and operations to create real-world AI-powered tools
What we offer
What we offer
  • Stock grant opportunities dependent on your role, employment status and location
  • Additional perks and benefits based on your employment status and country
  • The flexibility of remote work, including optional WeWork access
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer (APIs)

As a Senior Backend Engineer, you will contribute to the design and evolution of...
Location
Location
Spain , Madrid
Salary
Salary:
Not provided
parserdigital.com Logo
Parser Limited
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • 5+ years of professional software engineering experience with a Bachelor’s degree, or 3+ years with a Master’s degree
  • Strong backend engineering experience building and operating production systems at scale
  • Strong proficiency in JVM-based technologies, where Java and Kotlin are preferred, and Spring Boot
  • Experience designing and building APIs and integrations between distributed systems
  • Experience working with cloud-native architectures in public or hybrid cloud environments
  • Strong understanding of microservices, asynchronous processing, and service-oriented architectures
  • Experience with SQL and/or NoSQL databases and scalable data access patterns
  • Experience with observability, monitoring, logging, alerting, and production troubleshooting
  • Ability to design maintainable, modular, and testable systems with strong operational awareness
  • Understanding of software design principles, data structures, and distributed systems fundamentals
Job Responsibility
Job Responsibility
  • Design, build, and maintain scalable backend services and APIs using JVM technologies such as Java or Kotlin, and Spring Boot
  • Develop integration layers with third-party insurance and assurance providers
  • Build systems supporting the full Trip Protection lifecycle, including eligibility, quoting, purchase, servicing, claims, cancellations, and refunds
  • Design clean, maintainable, observable, and testable software using sound software engineering principles and design patterns
  • Create APIs and backend workflows consumed by multiple internal and external partners
  • Contribute to architecture and technical design discussions for moderately complex distributed systems
  • Collaborate cross-functionally with product, platform, compliance, finance, and partner teams
  • Support production systems through monitoring, debugging, troubleshooting, and operational improvements
  • Participate in code reviews and help guide engineering best practices across the team
  • Contribute to reporting, reconciliation, and operational data flows required to support the business
What we offer
What we offer
  • The chance to join an organization with triple-digit growth that is changing the paradigm on how software products are built
  • The opportunity to form part of an amazing, multicultural community of tech experts
  • A highly competitive compensation package
  • Medical insurance
  • Fulltime
Read More
Arrow Right

Senior Backend Engineer - Python / Threat Intelligence

Are you ready to join a team that's building the future of threat intelligence? ...
Location
Location
Czechia , Prague
Salary
Salary:
Not provided
rapid7.com Logo
Rapid7
Expiration Date
Until further notice
Flip Icon
Requirements
Requirements
  • A minimum of 5 years of software development experience in a production environment with deep proficiency in Backend technologies (Python), including Python libraries (eg. SQLAlchemy, Pydantic, Playwright, Pytest), API design, Databases, and Microservices
  • Experience with Cloud computing (e.g., GCP, AWS, or similar)
  • Experience with DevOps practices (CI/CD pipelines, etc.)
  • Experience with Databases (eg. ElasticSearch, Firestore, PostgreSQL, MongoDB)
  • Problem Solving: Strong creative problem-solving skills with a focus on system design and performance optimization
  • Attention to Detail: Excellent attention to detail and a commitment to high-quality technical execution
  • AI Proficiency: Hands-on approach to AI Research and the ability to integrate AI into production environments
  • Passionate and responsible team player with strong communication skills
  • You aren't afraid to challenge the status quo, bringing innovative thinking and a fresh perspective to complex problems
  • Understanding of the full lifecycle development process, including business and functional requirements, developing technical designs, implementation of scalable solutions, and object-oriented design
Job Responsibility
Job Responsibility
  • Take an active role in the design and planning of upcoming features and make well-reasoned decisions and tradeoffs in your areas of expertise
  • Develop, test, and deploy high-quality, efficient code across the full stack, adhering to best practices and coding standards
  • Lead AI Research & POCs to find innovative solutions for threat intelligence
  • Take an active role in high-level architectural thinking, working with both legacy code and greenfield projects
  • Investigate and resolve the most complex system defects and production issues, performing root cause analysis to implement permanent technical solutions
  • Partner with internal teams to ensure we are understanding and delighting our customers
  • Fulltime
Read More
Arrow Right