Senior Software Engineer, Developer Experience

Block•Bay Area, CA, United States of America, CA

12h•$185,200 - $326,800

About The Position

Block is hiring a Senior Software Engineer focused on Developer Experience. The role builds tooling and agent workflows that enable engineers and autonomous agents to make changes to large monorepos quickly and safely. The engineer will own interfaces that help people observe, steer, and provide context to agents, and create guardrails that help control codebase complexity as agents take on larger tasks. The work includes enabling large-scale framework upgrades, language migrations, and dependency updates through agent workflows rather than primarily making those changes by hand. This is a high-leverage role in which improvements can benefit the broader engineering organization. The engineer will also shape technical direction, mentor other engineers, partner with engineering and other builders, and measure the adoption and impact of shipped tools.

Requirements

Experience shipping developer tools used by engineers daily, such as CLIs, desktop integrations, configuration management, or internal platforms, including driving adoption, debugging problems, and supporting users.
Experience building agent workflows that complete work that would normally take a team weeks, and deep understanding of agentic loops, including tool use, context management, verification, and failure handling.
Deep experience with application or platform frameworks, including upgrading and managing their evolution.
Track record leading migrations or large refactors from planning through rollout.
Significant experience working in large, complex codebases; typically 7 or more years for Senior roles.
Strong communication skills and ability to build trust with teams by owning work outcomes.

Nice To Haves

Experience with harness engineering or context engineering.
Experience with agent observability, for example through OpenTelemetry.
Experience distributing internal tools through versioning, release channels, and auto-update, and measuring adoption with telemetry or surveys.
Background in developer productivity metrics, test infrastructure, or CI/CD.
Passion for intuitive user experience and elegant solutions.
Open-source contributions to developer tooling or agent frameworks.

Responsibilities

Build, ship, support, and drive adoption of developer tools such as CLIs, desktop integrations, and interfaces for observing, unblocking, and steering autonomous agents.
Design and evolve agentic loops, harnesses, skills, and context that enable agents to perform engineering work reliably.
Build agent workflows for large-scale codebase changes, including framework upgrades, language migrations, and dependency updates, while minimizing disruption to product teams.
Develop guardrails, tests, and automation that make large agent-authored changes safe to land, and track indicators of growing codebase complexity.
Identify and address root causes of friction in development workflows for people and agents.
Partner with builders inside and outside engineering to understand their pain points and measure the adoption and impact of shipped work.
Set technical direction and mentor engineers on agent design, tooling, and codebase health.