Senior Software Engineer, Developer Experience
Summary
Improves developer experience across Block's (Square, Cash App) largest monorepos: leads framework and language migrations, keeps dependencies and build/CI infrastructure healthy, and designs agentic AI workflows so large changes land safely. Key tech: Bazel-style build systems, codemods/AST tooling, LLM-based coding tools.
Block is one company built from many blocks, all united by the same purpose of economic empowerment. The blocks that form our foundational teams — People, Finance, Counsel, Hardware, Information Security, Platform Infrastructure Engineering, and more — provide support and guidance at the corporate level. They work across business groups and around the globe, spanning time zones and disciplines to develop inclusive People policies, forecast finances, give legal counsel, safeguard systems, nurture new initiatives, and more. Every challenge creates possibilities, and we need different perspectives to see them all. Bring yours to Block.
The Role
Our engineers are only as effective as the tools, codebase, and workflows around them. As a Developer Experience Engineer, you’ll make our large, evolving codebase easier to build, change, and reason about, for both human developers and AI agents.
You will be responsible for the developer experience in our largest monorepos: building tools for and driving framework and language migrations, keeping dependencies healthy, improving build and test infrastructure, and shaping how agentic workflows operate in our development process. This is a high-leverage role. Every improvement you ship multiplies across the whole engineering organization.
What you’ll do
- Lead and execute large-scale changes across the codebase, including framework upgrades, language migrations, and dependency updates, with minimal disruption to product teams
- Design and evolve agentic loops: the plan, act, verify, and iterate cycles that let AI agents do real engineering work safely and reliably
- Identify friction in the developer workflow (slow builds, flaky tests, confusing abstractions) and fix the root causes
- Improve build tooling and CI performance, including work with Bazel or a comparable build system
- Build the guardrails, tests, and automation that make large, automated changes safe to land
- Partner with product engineering teams to understand their pain points and measure the impact of your work
- Set technical direction and mentor other engineers on migration strategy, tooling, and codebase health
What we’re looking for
Required
- Significant experience (typically 7+ years for Senior, 10+ for Staff) working in large, complex codebases
- Deep experience with application or platform frameworks, including upgrading them and managing their evolution over time
- Track record of leading migrations or large refactors, from planning through rollout
- Comfort navigating unfamiliar code quickly and making sound changes across many teams’ areas
- A solid understanding of agentic loops (tool use, context management, verification, failure handling) and a genuine willingness to keep investing in and evolving them as the field changes
- Strong communication skills and the ability to build trust with teams whose code you’re changing
Nice to have
- Hands-on experience with Bazel or similar build systems (Buck, Pants, Nx, Gradle, etc.)
- Experience with codemods, AST-based tooling, or automated refactoring at scale
- Background in CI/CD, test infrastructure, or developer productivity metrics
- Experience building or integrating LLM-based coding tools into engineering workflows
- Open source contributions to build tools, frameworks, or developer tooling
Block takes a market-based approach to pay, and pay may vary depending on your location. U.S. locations are categorized into one of four zones based on a cost of labor index for that geographic area. The successful candidate’s starting pay will be determined based on job-related skills, experience, qualifications, work location, and market conditions. These ranges may be modified in the future.
To find a location’s zone designation, please refer to this resource. If a location of interest is not listed, please speak with a recruiter for additional information.
Application Guidelines
Candidates may submit up to 9 active applications within a 60-day period. Reapplications to the same role are accepted 90 days after a previous application has been reviewed.
Use of AI in Our Hiring Process
We may use automated AI tools to evaluate job applications for efficiency and consistency. These tools comply with local regulations, including bias audits, and we handle all personal data in accordance with state and local privacy laws.
Contact us here with hiring practice or data usage questions.
Every benefit we offer is designed with one goal: empowering you to do the best work of your career while building the life you want. Remote work, medical insurance, flexible time off, retirement savings plans, and modern family planning are just some of our offering. Check out our other benefits at Block.
Block, Inc. (NYSE: XYZ) builds technology to increase access to the global economy. Each of our brands unlocks different aspects of the economy for more people. Square makes commerce and financial services accessible to sellers. Cash App is the easy way to spend, send, and store money. Afterpay is transforming the way customers manage their spending over time. TIDAL is a music platform that empowers artists to thrive as entrepreneurs. Bitkey is a simple self-custody wallet built for bitcoin. Proto is a suite of bitcoin mining products and services. Together, we’re helping build a financial system that is open to everyone.
Privacy Policy
Skills
As published by greenhouse · 16 questions · 2 written answers
Basics
First Name, Last Name, Email, Phone, Resume/CV, Cover Letter, Location
Short answers (7)
- LinkedIn Profile optional
- Additional profiles (e.g. GitHub, Stack Overflow) optional
- If you answered "Yes" to the question above, please enter your dates of employment. Note that your performance history may be reviewed as part of the application process. optional
- If you answered "Yes" to the question above, please enter your dates of contract engagement or work through agency. optional
- I certify that all of the information I have provided is correct and complete and realize that falsification or misrepresentation, including omission, on this or any other personnel record, or in the hiring process, may be grounds for refusal of employment, or if hired, may lead to disciplinary action, up to and including termination. By signing this Electronic Signature Acknowledgment Online Form, I agree that my electronic signature is the legally binding equivalent to my handwritten signature. Whenever I execute an electronic signature, it has the same validity and meaning as my handwritten signature. I will not, at any time in the future, repudiate the meaning of my electronic signature or claim that my electronic signature is not legally binding. Please sign by typing your Full Legal First, Middle Initial, and Last Name.
- What is your Legal First Name?
- What is your Legal Last Name?
Pick from a list (7)
- Will you now or in the future require sponsorship for work authorization? (This information will not be used in assessing your qualifications for any position.)
- Are you authorized to work lawfully in the location posted for this position?
- Have you ever been employed full-time at Block or its subsidiaries?
- Have you ever provided any contract work for Block, Inc. or any of its subsidiaries or affiliates (whether in the U.S. or internationally)?
- By clicking “accept,” you agree that any disputes related to your application, including those related to Block’s selection process, hiring decision, and your background check, shall be submitted to binding arbitration with the Judicial Arbitration and Mediation Services, Inc. (JAMS) on an individual basis only in San Francisco, before a single arbitrator according to the applicable JAMS Rules then in effect, with Block bearing all costs unique to arbitration. To the extent permitted by law, you and Block each waive the right to initiate or participate in any class, collective, or representative action against the other in any forum (including court and arbitration). If any provision of this agreement is deemed unenforceable, the remainder shall remain in effect, except that, notwithstanding the above, under no circumstances shall class or collective, or representative proceedings be permitted in arbitration.
- How we interview: Our hiring process prioritizes authenticity and fairness, and we ask all candidates to adhere to a few key expectations. Acceptable use of AI may differ depending on the role, so we encourage you to confirm with your recruiter what is or isn’t permitted during the process. Recording any part of the interview without consent is prohibited. However, if you need recording as an accommodation, please notify your recruiter before your scheduled interview. During virtual interviews, keep your video on to foster meaningful engagement; if you require accommodations, please inform our team in advance. Lastly, maintain confidentiality by refraining from sharing any proprietary or trade secret information from previous employers or other sources throughout the interview process.
- With your permission, we may use AI transcription software to transcribe and summarize your interview to help us capture accurate notes. Participation is entirely voluntary, and your decision will not affect the outcome of your application. You can withdraw consent at any time. Do you consent to us using AI to transcribe and summarize your interview?
Written answers (2)
- Tell us a bit about why you're applying to work here. What excited you about this role? optional
- Block's purpose is economic empowerment. Briefly tell us about what that purpose means to you. optional
