Senior Verification — LSU (Load/Store Unit) and Data Cache

ID: SV-LSU

Description

Role summary

Own verification of the Load/Store Unit, data cache and bus interfaces for a CPU/GPU core — the block handling memory ordering, address generation, cache/TLB interaction, forwarding, and exception handling. Contribute to drive the LSU from RTL freeze to tapeout-quality sign-off.

Responsibilities* Define and own the LSU verification plan: functional coverage, testplan, checkers, and closure criteria

• Build/extend UVM testbench components for LSU (drivers, monitors, scoreboards, memory models)
• Develop directed and constrained-random tests covering store-to-load forwarding, memory ordering (RISC-V WMO model), speculative loads, vector accesses, misaligned/split accesses, exceptions/faults, and pipeline hazards
• Drive formal verification for ordering/coherence properties where simulation coverage is weak
• Debug RTL/testbench failures in collaboration with design; triage and root-cause

Track and close functional/code coverage; report verification status to program * s

Mentor* verification engineers; review testbench code and testplans

Interface with architecture, design, and DV * s on other units to resolve cross-unit issues.

Why Seynamics?* Work at one of Europe's most promising deep-tech semiconductor scale-ups.

• Accelerated development path.
• 4 days per week in the Barcelona office (city center), 1 WFH day.
• 1 week of work from everywhere in the world.
• Competitive package.
• A collaborative, technical, and growth-oriented environment that values direct ownership and clear thinking.

Requirements

Required qualifications* BS/MS in EE/CE/CS, 5+ years in ASIC functional verification.

• Strong SystemVerilog/UVM experience; hands-on testbench architecture
• Deep understanding of memory subsystems: cache hierarchies, TLBs, memory consistency models, load/store pipelines
• Knowledge of RISC-V ISA and privileged specification is mandatory
• Knowledge of AMBA AXI4, AXI5Lite and CHI is mandatory
• Experience with coverage-driven verification and regression management
• Debugging complex RTL failures using waveform tools (Verdi/DVE or similar)

Preferred* Formal verification experience (JasperGold or similar) applied to memory ordering/coherence

• Knowledge of CPU architecture and memory execution pipeline
• Prior LSU, cache, or memory-controller verification specifically
• Experience with RISC-V, ARM, or x86 memory models
• Scripting (Python/Perl) for verification infrastructure and regression automation

Prior team* or mentorship experience

Nice to Have* Emulation platforms (Veloce, ZeBu)

• Familiarity with fuzzing techniques (AFL++)
• Knowledge of SystemC/C++ testbenches

Essential Soft Skills* An adversarial, gap-seeking mindset — instinctively asks "who actually checks this?" — collaborative relationship with the whole core.

• Clear communication across DV, design, and software teams; writes verification plans others can follow.

SENIOR