Senior Backend Engineer - Performance

Weave•Lehi, UT

1d•Remote

About The Position

Weave is looking for a foundational Senior Backend Engineer - Performance to establish and lead our performance engineering practice. Weave recently acquired Truelark, and we are preparing to onboard a massive wave of new customers onto their platform. Your first mission will be to ensure the Truelark platform can scale flawlessly, directly safeguarding customer experience and revenue during a critical business transition. This is a high-stakes, high-impact challenge that requires immediate, expert-level engagement to define performance baselines, identify bottlenecks, and guarantee reliability under unprecedented load. Beyond this initial challenge, you will be the founding member of Weave's performance engineering discipline. Your long-term strategic mission is to tackle the complex, "third-order" performance issues that arise in our distributed microservices architecture—the subtle inflection points between services that are a leading cause of incidents. This involves moving beyond testing individual components to understanding and fortifying the systemic behavior of our entire platform. As a key member of the Test Infrastructure team, your mandate is not just to test, but to build. You will create the paved-road for performance testing at Weave, developing frameworks, tooling, and reference implementations that empower hundreds of engineers to "move fast without breaking things". This role requires a platform-oriented mindset, where the primary goal is to enable and multiply the efforts of others, embedding performance as a core component of the software development lifecycle at Weave. This is a unique opportunity to build a critical engineering function from the ground up, with the autonomy to select tools, define methodologies, and shape the future of reliability and performance at a rapidly growing public company. If you are a software engineer with a passion for performance, a talent for building developer-centric tools, and a drive to solve complex systems-level challenges, we want to hear from you. This position will be remote, in the US

Requirements

5+ years (for Senior level) or 8+ years (for Staff level) of professional experience in roles such as Performance Engineer, Software Engineer in Test, SRE, DevOps, or Software Engineer with a deep focus on the performance, scalability, and reliability of large-scale distributed systems.
Strong software development fundamentals and significant hands-on experience building, testing, and maintaining complex applications or infrastructure using Go and/or Python. Proficiency in Go is highly desired to align with our primary backend language and to contribute effectively to our microservices ecosystem.
Deep, hands-on expertise with Kubernetes concepts, architecture, and workflows is required. This includes experience deploying and managing containerized applications, as well as understanding the nuances of performance tuning within a Kubernetes environment.
Proven ability to design, implement, and optimize complex CI/CD pipelines to integrate automated testing, including performance testing. Experience with tools like GitLab CI, GitHub Actions, or similar is essential.
Expert-level understanding of performance testing methodologies, including load, stress, spike, endurance, and scalability testing. Demonstrable experience designing and implementing test strategies for complex microservice architectures, including identifying appropriate metrics and acceptance criteria.
Exceptional analytical, debugging, and problem-solving skills with a proven ability to diagnose and solve complex, cross-service performance issues in distributed systems. You don't just find bottlenecks; you understand the systemic reasons they occur and can articulate the broader architectural implications.
Excellent communication skills (verbal and written) with the ability to articulate complex technical ideas clearly and effectively to diverse audiences, including engineers, product managers, and leadership.

Nice To Haves

Hands-on experience with modern, script-as-code performance testing tools, particularly k6 (preferred) or Locust. Experience building custom tooling, libraries, or frameworks around these tools to enhance developer experience is a significant plus. This demonstrates an alignment with our "test-as-code" and developer-enablement philosophy.
Proficiency with modern observability stacks (e.g., Prometheus, Grafana, Datadog, ELK) and extensive experience using metrics, distributed traces, and logs to correlate application performance with underlying system behavior during performance tests.
Experience with Go-specific profiling and debugging tools (e.g., pprof). Familiarity with the xk6-g0 extension for writing k6 tests directly in Go would also be a plus, as it represents a unique and powerful intersection of the exact skills required for this role: deep Go expertise combined with a modern approach to performance engineering.
A proven track record of building internal developer tools, platforms, or frameworks that have measurably improved engineering productivity, velocity, and software quality within an organization.
Direct experience testing Go-based microservices environments and systems utilizing Kafka, NSQ, Postgres, and/or gRPC.

Responsibilities

Architect and Execute Performance Strategy for Truelark Scaling: Immediately take the lead on the end-to-end performance testing, analysis, and tuning for the newly acquired Truelark platform. This involves defining key performance indicators (KPIs) and service level objectives (SLOs) based on business requirements, establishing performance baselines, and executing a comprehensive suite of load, stress, spike, and endurance tests. Your work will be critical to ensuring the system can handle the projected influx of Weave customers without degradation, directly preventing customer churn and protecting revenue.
Design and Build a Self-Service Performance Testing Platform: Architect, build, and maintain a scalable, automated performance testing framework deeply integrated into our CI/CD pipelines (e.g., GitLab CI, GitHub Actions). The ultimate goal is a "paved road" experience that enables any developer at Weave to easily configure, execute, and analyze performance tests for their services with minimal friction. This platform should be built with a developer-centric mindset, abstracting away the complexity of infrastructure provisioning and test execution while providing powerful, actionable results.
Champion and Codify Performance Best Practices: Develop and document reference implementations for performance testing critical path systems, particularly our Go-based microservices running on Kubernetes. You will create clear documentation, run workshops, and act as the organization's subject matter expert on performance engineering. A key part of this responsibility is to address the "knowledge and process gaps" around performance testing methodologies that currently exist at Weave, fostering a culture where performance is a shared responsibility.
Conduct Deep-Dive Bottleneck Analysis and System Tuning: Go beyond surface-level metrics to perform deep root cause analysis of performance bottlenecks in our distributed architecture. You will be responsible for investigating and debugging the "3rd order" incidents that arise from complex service interactions. This requires leveraging advanced observability tools (Prometheus, Grafana, Datadog) and application profiling tools to provide concrete, actionable recommendations to service owners for code and infrastructure improvements.
Define and Monitor Service Level Objectives (SLOs): Partner closely with infrastructure and product teams to define, measure, and monitor SLOs for latency, throughput, and availability of critical services. You will use the performance testing platform to continuously validate that services can meet their SLOs under various load conditions and proactively identify performance regressions before they impact customers in production. This work directly connects the performance engineering function to Weave's broader reliability and customer satisfaction goals.