Staff Design Verification Engineer – CPU Core Formal Verification

SiFive; California (MO); On-site; USD 140,000 - 170,000; Full time

Job summary

SiFive is seeking a Staff Design Verification Engineer to drive formal verification of high‑performance CPU core functionality. You will own verification plans, develop property sets, and mentor other engineers in formal methods.

You will collaborate with architecture, RTL, and simulation DV teams to improve proof convergence and verification quality on out‑of‑order cores. You will apply formal techniques to frontend, midcore control, issue logic, and memory/order handling, shaping scalable

Qualifications

• Bachelor's or Master's degree in Electrical Engineering, Computer Engineering, Computer Science, or a related field.
• 7+ years of ASIC, CPU/core, or SoC design verification with significant ownership for a Staff role.
• Direct experience with CPU/core verification and solid understanding of computer architecture and CPU microarchitecture.
• Hands-on experience with formal verification for RTL, including assertion-based verification, proof analysis, abstraction techniques, and closure of non-trivial properties.
• Experience developing assertions and formal strategies for control-heavy, ordering-sensitive, or interface-sensitive hardware behavior.
• Strong debugging skills across specification, RTL, properties, and verification infrastructure.
• Familiarity with scripting or programming in Python, Perl, Tcl, or similar languages used for automation and infrastructure.

Responsibilities

• Own formal verification planning and execution for one or more high-performance out-of-order CPU core areas, from block-level proof strategy through signoff-oriented closure.
• Develop formal verification plans based on architectural intent and microarchitectural risk, including assumptions, assertions, covers, abstraction strategy, and closure criteria.
• Create and maintain scalable formal environments, property sets, checkers, harnesses, and proof infrastructure for complex CPU control, ordering, and interface behavior.
• Target high-value CPU verification problems such as pipeline control, issue and dispatch correctness, flush and replay behavior, register/data movement correctness, load-store ordering, hazard handling, forward progress, and clock-gating correctness.
• Use the right mix of abstraction, decomposition, bounded proofs, connectivity checks, X-prop style reasoning, and bug-hunting strategies to improve proof convergence and debug efficiency.
• Analyze proof failures, counterexamples, vacuity, over-constraint, and incompleteness, and drive fixes across RTL, properties, assumptions, and verification infrastructure.
• Partner closely with architecture, RTL, and simulation-focused DV engineers to review specifications, identify ambiguities early, and align formal results with broader verification goals.
• Contribute reusable formal methodology, automation, debug workflows, and infrastructure that improve productivity and verification quality across future CPU core programs.
• Mentor other engineers through reviews, property-quality guidance, and formal-debug best practices.

Skills

Debugging skills

Ownership

Verif methodology

Python scripting

Collaboration

Mentoring

Education

Bachelor's or Master's in Electrical Engineering / Computer Engineering / Computer Science

Tools

Formal verification tooling

RTL assertions & proofs

Job description

As the pioneers who introduced RISC-V to the world, SiFive is transforming the future of compute by bringing the limitless potential of RISC-V to the highest performance and most data-intensive applications in the world. SiFive's unrivaled compute platforms are continuing to enable leading technology companies around the world to innovate, optimize and deliver the most advanced solutions of tomorrow across every market segment of chip design, including artificial intelligence, machine learning, automotive, data center, mobile, and consumer. With SiFive, the future of RISC-V has no limits. At SiFive, we are always excited to connect with talented individuals, who are just as passionate about driving innovation and changing the world as we are. Our constant innovation and ongoing success is down to our amazing teams of incredibly talented people, who collaborate and support each other to come up with truly groundbreaking ideas and solutions. Solutions that will have a huge impact on people's lives; making the world a better place, one processor at a time. Are you ready? To learn more about SiFive's phenomenal success and to see why we have won the GSA's prestigious Most Respected Private Company Award (for the fourth time!), check out our website and Glassdoor pages.

Job Description

SiFive is looking for a Staff Design Verification Engineer to drive formal verification of high-performance CPU core functionality.

This is a Staff individual-contributor role within the CPU Design Verification organization, focused on applying formal methods to complex out-of-order CPU core microarchitecture. The role is aimed at an engineer who can independently own difficult verification problems, define strong property-driven verification strategies, identify risk early, and improve verification quality across the broader CPU DV effort.

The primary technical scope includes formal verification of CPU core units such as frontend, midcore control logic, issue and commit behavior, load-store interactions, clock-gating and control logic, and other bounded or high-risk microarchitectural behaviors where exhaustive reasoning provides strong value.

Responsibilities

• Own formal verification planning and execution for one or more high-performance out-of-order CPU core areas, from block-level proof strategy through signoff-oriented closure.
• Develop formal verification plans based on architectural intent and microarchitectural risk, including assumptions, assertions, covers, abstraction strategy, and closure criteria.
• Create and maintain scalable formal environments, property sets, checkers, harnesses, and proof infrastructure for complex CPU control, ordering, and interface behavior.
• Target high-value CPU verification problems such as pipeline control, issue and dispatch correctness, flush and replay behavior, register/data movement correctness, load-store ordering, hazard handling, forward progress, and clock-gating correctness.
• Use the right mix of abstraction, decomposition, bounded proofs, connectivity checks, X-prop style reasoning, and bug-hunting strategies to improve proof convergence and debug efficiency.
• Analyze proof failures, counterexamples, vacuity, over-constraint, and incompleteness, and drive fixes across RTL, properties, assumptions, and verification infrastructure.
• Partner closely with architecture, RTL, and simulation-focused DV engineers to review specifications, identify ambiguities early, and align formal results with broader verification goals.
• Contribute reusable formal methodology, automation, debug workflows, and infrastructure that improve productivity and verification quality across future CPU core programs.
• Mentor other engineers through reviews, property-quality guidance, and formal-debug best practices.

Minimum Qualifications

• Bachelor's or Master's degree in Electrical Engineering, Computer Engineering, Computer Science, or a related field.
• 7+ years of relevant experience in ASIC, CPU/core, or SoC design verification, with strong hands-on ownership of complex verification problems appropriate for a Staff role.
• Direct experience with CPU/core verification and solid understanding of computer architecture and CPU microarchitecture.
• Strong hands-on experience with formal verification for RTL, including assertion-based verification, proof analysis, abstraction techniques, and closure of non-trivial properties.
• Experience developing assertions and formal strategies for control-heavy, ordering-sensitive, or interface-sensitive hardware behavior.
• Strong debugging skills with the ability to root-cause issues across specification, RTL, properties, and verification infrastructure.
• Strong understanding of verification methodology, including test planning, failure analysis, coverage thinking, and signoff discipline.
• Familiarity with scripting or programming in Python, Perl, Tcl, or similar languages used for automation and infrastructure.

Preferred Qualifications

• Experience with out-of-order CPU core verification.
• Experience applying formal methods to CPU core areas such as frontend control, issue logic, scoreboarding, commit, LSU ordering behavior, MMU/TLB control, or power / clock-gating logic.
• Experience with formal techniques for safety, liveness, deadlock, forward progress, connectivity, reset, and microarchitectural consistency checks.
• Experience balancing formal and simulation approaches, including identifying when a problem is best solved through exhaustive proof versus dynamic verification.
• Experience improving formal convergence through abstraction, environment modeling, assume-guarantee decomposition, and scalable proof planning.
• Experience collaborating across architecture, RTL, formal, and design verification teams in a fast-moving CPU development environment.
• Experience mentoring engineers and influencing verification methodology beyond immediate ownership scope.

Additional Information

In addition to base pay, this role may be eligible for variable/ incentive compensation and/ or equity. In addition, this role is eligible for a comprehensive, competitive benefits package which may include healthcare and retirement plans, paid time off, and more!

This position requires a successful background and reference checks and satisfactory proof of your right to work in United States of America

Any offer of employment for this position is also contingent on the Company verifying that you are an authorized for access to export-controlled technology under applicable export control laws or, if you are not already authorized, our ability to successfully obtain any necessary export license(s) or other approvals.

SiFive is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees.

As an E-Verify employer, we use this system to confirm the employment eligibility of all new hires in accordance with federal law. All applicants will be required to complete a Form I-9, Employment Eligibility Verification, upon hire. We do not use E-Verify to pre-screen job candidates and will comply with all E-Verify regulations.