Source Job

North America

  • Take deep ownership of key systems and product areas, becoming the technical expert and primary point of reference.
  • Architect, build, and maintain highly available and scalable REST APIs and backend services.
  • Use agentic development workflows and AI coding tools as standard engineering practice.

Python Go Rust AWS Kubernetes

20 jobs similar to Senior Fullstack Engineer, Customer Context US Security & IT

Jobs ranked by similarity.

North America Unlimited PTO

  • Take deep ownership of systems and product areas, becoming the go-to technical expert for what you own.
  • Architect, build, and maintain highly available, scalable REST APIs and backend services across distributed systems.
  • Build agentically with AI coding tools, staying at the forefront of emerging AI tooling and practices.

Postscript is an AI messaging platform for Shopify brands, helping e-commerce marketers drive revenue through SMS marketing and AI features. Backed by Greylock and Y Combinator, the company has been fully remote since 2018 and serves 20,000+ Shopify brands with a culture of ownership and AI-first development.

$200,000–$230,000/yr
US Unlimited PTO

  • Lead a team of backend engineers on Core Services, owning people, execution, and outcomes.
  • Stay technically credible on critical-path systems, reviewing designs and debugging as needed.
  • Champion an AI-native culture, using AI heavily in your own work and coaching the team.

Benepass provides a fintech platform that lets companies customize benefits for their employees' individual needs. Backed by leading investors, the company has raised ~$75M in equity and was listed on Inc. Magazine's Best Workplaces of 2023. They foster a culture of high trust, accountability, and AI-native work.

Canada Unlimited PTO

  • Design and build scalable backend systems, APIs, and data models that power communications, experimentation, and personalization.
  • Partner with Product, Data Science, and Experience teams to define and execute strategies for customer acquisition and engagement.
  • Mentor and support junior engineers, contributing to a culture of learning, collaboration, and technical excellence.

Affirm is a financial technology company that provides point-of-sale installment loans to consumers, allowing them to pay over time with no hidden fees. The company is remote-first and values transparency, care, and flexibility, with a strong emphasis on employee well-being and professional growth.

$204,000–$290,000/yr
US Unlimited PTO

  • Set technical strategy for the team and drive large-scale, business-impacting projects.
  • Collaborate with product, design, and analytics to ensure technical sustainability and manage trade-offs.
  • Foster engineering quality and talent development through code review standards and mentorship.

Affirm is a financial technology company that provides transparent, flexible payment solutions, allowing consumers to pay over time without hidden fees. The company is remote-first and values inclusivity, offering competitive benefits and a collaborative culture.

Canada

  • Design and implement the core AI agent runtime in Python, including orchestration loops, tool definitions and execution, memory and context management, and failure handling.
  • Build and maintain evaluation datasets, automated evaluators, LLM-as-judge pipelines, and regression tracking to ensure agent quality and performance.
  • Develop Python and Node.js microservices for agent hosting and LLM interactions, and build reliable Laravel/PHP APIs for integration.

Jobgether is a platform that uses AI-powered matching to connect candidates with job opportunities, partnering with companies to manage applications and next steps. They emphasize a fast-growing, collaborative environment with a focus on professional growth and cutting-edge technology.

$160,000–$200,000/yr
United States Canada Europe Unlimited PTO 12w maternity 12w paternity

  • Write reliable, secure, scalable code for real-time authorization and fraud-prevention systems.
  • Build customer-facing features like rules improvements, velocity controls, and fraud tooling.
  • Own projects from planning to launch and participate on on-call rotation.

Lithic is the modern card issuing and processing platform empowering ambitious financial companies to build the future of payments. We are a team of 170+ across 26 states and 7 countries, headquartered in New York City.

Canada Unlimited PTO

  • Work with technical leaders to design and implement forward-looking approaches for checkout systems.
  • Own components of checkout systems and define their long-term health.
  • Collaborate with engineers to build the next generation of the checkout platform.

Affirm provides a clear, predictable way to pay over time through buy now, pay later solutions. It is a remote-first company with a culture focused on honesty, trust, and customer-centric innovation.

$170,000–$235,000/yr
US

  • Design and implement backend services for licensing, entitlements, feature access, and usage limits across NodeZero's product and APIs.
  • Build and evolve provisioning, admin experience, MSP/MSSP capabilities, and audit logging for a multi-tenant SaaS platform.
  • Operate production services with monitoring, incident response, and a high bar for design quality and test coverage.

Horizon3 is a fast-growing, remote cybersecurity company that helps organizations proactively find, fix, and verify exploitable attack vectors through its NodeZero autonomous pentesting platform. The team is a fusion of former special operations cyber operators and startup engineers, fostering a culture of respect, collaboration, ownership, and results.

UK Unlimited PTO

  • Own and deliver quarterly goals for your team, leading engineers through ambiguity and ensuring support throughout delivery.
  • Collaborate with product management, design, and analytics to articulate technical constraints and partner on decisions with risk and trade-offs.
  • Foster a culture of quality by setting code review and design standards, and develop talent through feedback and guidance.

Affirm provides a clear, predictable way to pay over time, with no hidden fees or surprises. We are a remote-first company serving over 20 million people, with a culturally rooted Silicon Valley team spread across Europe.

$193,461–$291,000/yr
US

  • Work on core infrastructure powering Arbitrum, tackling distributed systems challenges and optimizing performance.
  • Collaborate with research, product, and blockchain engineering teams at the cutting edge of blockchain technology.
  • Establish backend architectural standards and drive technical roadmap for complex distributed systems.

Offchain Labs is a pioneer in blockchain scalability and security, building the Arbitrum stack that powers the leading Ethereum scaling solution. Backed by $124 million in funding, our team of thinkers and doers embraces new challenges and pushes boundaries.

US 18w maternity 12w paternity

  • Build and improve customer-facing package registries, APIs, and artifact-serving systems for secure software consumption.
  • Develop and operate backend services in Go, owning projects from technical design through deployment and iteration.
  • Collaborate across engineering and product teams to enhance scalability, reliability, and observability of production systems.

This partner company builds secure, reliable systems for serving software artifacts at scale, including customer-facing registries and APIs. It is a collaborative, remote-first environment focused on engineering ownership and continuous learning.

US Unlimited PTO

  • Drive technical strategy for the card loan platform by leading planning and execution of projects.
  • Design and develop large-scale, high-availability services with robust APIs and data models.
  • Collaborate across functions with product, analytics, and other teams to define requirements and execute card loan strategy.

Affirm provides a clear, predictable way to pay over time for purchases, with no hidden fees. It is a remote-first company experiencing explosive growth and fostering a culture of care, transparency, and flexibility.

$139,200–$235,200/yr
Canada United States Unlimited PTO

  • Design, build, and operate GitLab Orbit backend services, primarily in Rust, within a distributed, cloud-native environment.
  • Improve deployment, monitoring, and operations using Kubernetes, Helm, Terraform, and cloud services from AWS or GCP.
  • Automate operational work, strengthen observability, and manage production issues to reduce single points of failure.

GitLab is the intelligent orchestration platform for DevSecOps, helping organizations increase developer productivity, improve operational efficiency, and accelerate digital transformation. Trusted by more than 50 million registered users and over 50% of the Fortune 100, GitLab fosters a high-performance culture driven by shared values and continuous knowledge exchange.

Global

  • Build LLM-based agents on the platform's scaffolding, integrating tool calls, internal APIs, and guardrails.
  • Take agents to production on AWS with containers, CI/CD, secrets, permissions, and security controls.
  • Define and run evals, monitor with Langfuse, and document runbooks for independent operation.

Muttdata builds innovative Data Products and Machine Learning solutions to help companies solve complex business challenges. It is a fast-growing, remote-first startup that values collaboration, continuous learning, and a positive, ownership-driven culture.

US

  • Design, develop, and launch backend systems at scale using Python or Kotlin.
  • Collaborate with team and stakeholders to balance speed and quality while protecting system reliability.
  • Contribute to community through growth and development activities and navigate large codebases.

Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without hidden fees. They are a remote-first company that values transparency and employee well-being, offering competitive benefits and a collaborative culture.

US Unlimited PTO

  • Design, build, and maintain core services and infrastructure that power large-scale logistics solutions.
  • Identify and address performance bottlenecks, ensuring reliability and scalability across the platform.
  • Collaborate closely with Product, Data Science, and other engineering teams to deliver impactful features.

Roadie is a logistics and delivery platform that helps businesses tackle delivery complexities with same-day and last-mile solutions. With over 310,000 independent drivers nationwide and a remote-first culture, Roadie values innovation, collaboration, and flexibility.

$85,000–$115,000/yr
US

  • Build and scale automated data pipelines across analytics, legal, and commissions.
  • Integrate CRM, billing, and finance systems using custom APIs and data pipelines.
  • Ship and maintain internal applications and deploy containerized AWS services.

LeanTaaS builds AI-powered software that helps hospitals optimize capacity by reducing wait times and costs. With over $300 million in funding from top investors, the company serves more than 190 health systems and employs a culture focused on innovation and operational excellence.

UK

  • Design and ship backend features that shape a global platform, making sound architectural trade-offs.
  • Mentor engineers, define standards, and drive quality, security, and operational excellence.
  • Integrate agentic AI into production workflows and collaborate with PMs and designers to deliver user value.

GitLab is the intelligent orchestration platform for DevSecOps, helping organizations increase developer productivity and accelerate digital transformation. Trusted by more than 50 million registered users and over half of the Fortune 100, GitLab fosters a remote-first, AI-driven culture where every voice is valued.

Europe 5w PTO

  • Build and operate Python/Django services for repairs, payments, messaging, notifications, and fraud prevention.
  • Work in cross-functional product teams using AI-assisted, spec-driven development from design through delivery.
  • Ensure reliability and data integrity through automated testing, observability, security, and incident response.

Plentific is a property technology platform for housing providers, local authorities, and contractors in the UK and Germany. We are a growing London-headquartered team working across Europe to expand the platform and integrate AI.

US Unlimited PTO

  • Design and implement backend systems for trust and safety at scale.
  • Collaborate with product, design, and analytics to ensure technical sustainability.
  • Foster a culture of quality through code reviews, design standards, and mentoring.

Affirm provides a clear, predictable way to pay over time with no hidden fees. It is a remote-first company with a focus on engineering excellence and scalable solutions.