Flex is a growth-stage, NYC headquartered FinTech company that is creating the best rent payment experience. It’s hard to believe that it’s 2026 and paying rent on time is expensive, inflexible, and difficult. We’re here to change that! Flex enables our users to pay rent throughout the month on a schedule that better fits their finances and budget. Our mission is to empower as many renters as possible with flexibility over their most significant recurring expense. After deliberately keeping a stealth profile as we built up unprecedented investor support and an enthusiastic user base, we are looking for motivated individuals to help us keep our mission growing. Will you be a part of the team?
Flex is looking for a Senior Staff Infrastructure Engineer who owns outcomes, not just systems. You navigate ambiguity and competing priorities across engineering teams — resolving technical and organizational conflicts independently and building shared frameworks that create clarity and alignment. You translate complexity into clear plans and decisions, welcome debate because it produces better results, and stay composed under pressure when your teams need stability. You lead with curiosity, not ego, confident in your expertise, but genuinely open to being wrong.
You'll lead the technical strategy for our infrastructure platform, a small team responsible for the reliability, scalability, and developer experience that enables Flex to deliver for our customers. Your success isn't measured by the infrastructure you build; it's measured by the engineering velocity you unlock and the customer impact you enable.
You'll partner with engineering leaders across domains to identify where infrastructure capabilities can solve real business problems, shape roadmaps together, and deliver platforms that teams actually adopt. You anticipate what the org needs before they ask for it and you build the case with data, not intuition.
Flex is an AI-first engineering organization. At this level, that means more than using AI tools in your own workflow, it means driving AI-assisted engineering practices at scale across teams, setting governance for responsible use, and removing the organizational barriers that slow adoption. You combine deep domain expertise in cloud architecture and SRE with the judgment to know where AI adds leverage and where human decision-making is essential.
This is a remote role. We're looking for someone with 10+ years of cloud infrastructure experience and a software engineering background (Java, Python, or TypeScript) that lets you collaborate credibly with product teams and build the tooling and automation that raises the bar for the whole org.
What you’ll do
- Drive infrastructure strategy that connects to business outcomes. Define the technical direction for scalable, resilient infrastructure and partner with domain owners to ensure the roadmap reflects real customer needs and organizational priorities.
- Identify and unlock cross-domain opportunities. Proactively spot where infrastructure capabilities can enable new product possibilities or remove bottlenecks across engineering. Work with teams to quantify the impact on delivery speed, quality, and cost.
- Own the developer experience end-to-end. Architect self-service platforms, CI/CD systems, and deployment mechanisms that maximize organizational velocity. Measure adoption and iterate — the best platform is the one teams choose to use.
- Establish and scale SRE culture across engineering. Define SLOs/SLIs for critical infrastructure systems, lead high-severity infrastructure incident response across team boundaries, and drive post-incident reviews that produce systemic improvements.
- Raise the engineering bar through craftsmanship, not just oversight. Mentor engineers, lead design and code reviews, and set standards for quality and process that teams internalize. Your goal is to make the teams you work with permanently better.
- Partner with security to build trust into the platform. Ensure infrastructure meets regulatory and security requirements by design, not as an afterthought. Champion security-by-design principles across engineering so that secure defaults are the path of least resistance.
- Champion AI-assisted engineering and automation at organizational scale. Champion governance and quality guardrails for AI usage across teams, identify high-leverage opportunities, and help the org measure real impact. Design systems and pipelines that minimize operational toil by default — every manual process is a candidate for elimination, every incident a signal that the system should be more self-healing.
- Support cloud cost strategy across the engineering org. Contribute FinOps practices, cost visibility tooling, and allocation frameworks that give teams the context to understand and optimize their infrastructure spend.
- Cloud infrastructure at scale. Deep experience designing, building, and operating resilient AWS infrastructure (EKS, RDS, S3, API Gateway, DynamoDB/DocumentDB). You've made architectural decisions that held up over time.
- Infrastructure as Code at org scale. Track record driving Terraform best practices, reusable modules, and governance frameworks — not just for your team, but across engineering.
- Platform and developer tooling. Experience building internal platforms and CI/CD pipelines (GitHub Actions or equivalent) that measurably improved engineering productivity. You think in terms of adoption, not just capability.
- Observability as a practice. Defined and led implementation of metrics, logs, and traces frameworks (Datadog preferred) that transformed monitoring from reactive alerting to proactive operational insight.
- Networking and security fundamentals. Hands-on experience with service mesh (Istio), service discovery, VPC design, and security architecture in cloud environments.
- Technical communication and influence. You drive alignment on complex technical strategies across engineering, product, and leadership through clarity and evidence, not authority.
- Tier A (NYC/SF/Seattle): $240,000 - $300,000 USD
- Tier B: $216,000 - $270,000 USD
- Tier C: $204,000 - $255,000 USD
#LI-Remote
Life at Flex:
We understand that it takes a diverse team of highly intelligent, curious, determined, empathetic, and self aware people to grow a successful company. Our HQ is located in New York City, but we have employees located throughout the US, Australia, Canada and South America. We are growing quickly, but deliberately, with a focus on building an inclusive culture. Our dynamic team has incredible perspectives to share, just as we know you do, and we take great pride in being an equal opportunity workplace.
We offer many employee benefits & perks. For full-time U.S based positions we offer:
- Competitive medical, dental, and vision available from Day 1
- Company equity
- 401(k) plan with company match (our company match kicks off at the beginning of 2026)
- Unlimited paid time off + 13 company paid holidays
- Parental leave
- Flex Cares Program
- Free Flex subscription
For full time non-US employees, we offer
- Competitive compensation + company equity
- Unlimited PTO
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