Sr Principal Software Engineer

Senior Principal Software Engineer

Are you excited to work with a variety of products and technologies in a collaborative and supportive environment?

Do you enjoy sharing knowledge and learning with colleagues from diverse backgrounds?

About the Business:

At LexisNexis Risk Solutions Company, we believe in the power of data and advanced analytics for better risk management. With over 40 years of expertise, we are the trusted data analytics provider for organizations seeking actionable insights to manage risks and improve results while upholding the highest standards for security and privacy. Headquartered in metro Atlanta, LexisNexis Risk Solutions serves customers in more than 100 countries and is part of RELX Group plc, a world leading provider of information and analytics for professional and business customers across industries. For more information, please visit

About the Team

The LexisNexis Risk Solutions Threat Metrix engineering team is an international team that includes experts in device identification, device intelligence, fraud detection, high performance and low latency real time systems, Software as a Service (SaaS) applications, machine learning, and data analytics. We are an Agile engineering team using concepts such as Scrum, Continuous Integration, self organizing teams, and Continuous Improvement.

About the Role

Threat Metrix is looking for an experienced developer and systems engineer to work across multiple teams and components. This is not a normal scrum team developer role; this role spans teams and will be required to provide architecture, design, implementation, and review to a broad range of products and technologies across the Threat Metrix platform. There will be research and experimentation around the core principle of improving product efficiency. This is a challenging but fun role.

The Threat Metrix platform includes components such as

• High performance C++ servers providing low latency responses to customer queries from around the globe
• Java applications
• JavaScript and Web technologies applications, iOS and Android mobile apps
• Web portal architecture
• Big Data No SQL and SQL

We are looking for an operating system, networks and/or data storage specialist to work with multiple in house applications to optimise code, configuration and tuning for our various high performance, low latency software components.

Responsibilities

• Drive production p95/p99 down and throughput up across services and data paths.
• Diagnose hotspots using tcpdump/pcap, kernel metrics and code runtime analysis.
• Tune Linux (RHEL/CentOS/Rocky/Alma) networking: sysctls, queues, IRQ affinity, RPS/RFS, backlog sizing, PMTU/IPv6.
• Read and fix performance issues in C++ (Java is a plus).
• Set client policy guardrails (timeouts/retries/back pressure/connection pools) to protect tail latency.
• Lead design and code reviews; write crisp experiment notes; mentor engineers across teams.

Required Technical Skills

• Proven production wins reducing tail latency (p95/p99) on RHEL/CentOS/Rocky/Alma systems.
• Fluency with packet and kernel observation: tcpdump/pcap, ss/netstat, /proc/net/ , sar, perf
• Concrete Linux networking tuning: SYN/accept backlog, socket buffers, GRO/GSO, PMTU/MSS clamp, IRQ/RPS/RFS/affinity, conn tracking nuances.
• Strong recent hands on in C++ (threading/lock contention) and bonus Java (GC ergonomics, thread pools, reactive/async).

Bonus Technical Skills

• NoSQL at scale (Aerospike/Scylla/Cassandra/Redis/Dynamo): data modelling, client policies, compaction/replication trade offs.
• TLS termination at scale, proxies/load balancers (Envoy/Nginx/A10), IPv6 edge cases.
• SRE practices: SLIs/SLOs, canaries, chaos, incident reviews.

Requirements

• Excellent written/spoken communication; can align multiple teams with data/presentations.
• Strategic thinking
• Team player who works effectively with others
• Detail Oriented and desire to learn/research/understand
• Ability to work with geographically dispersed teams in different timezones
• Ability to accept criticism and provide feedback (e.g. code reviews)

Experience

• 10+ years building high-performance systems with strong recent hands on in C++ (Java a bonus)
• 10+ years OS/kernel/networking configuration & optimisation on Linux in production
• Code reviews, CI, source control, bug tracking (Atlassian/Jira/Bitbucket or similar)
• Design & architecture for low-latency, high-throughput services

We are an equal opportunity employer: qualified applicants are considered for and treated during employment without regard to race, color, creed, religion, sex, national origin, citizenship status, disability status, protected veteran status, age, marital status, sexual orientation, gender identity, genetic information, or any other characteristic protected by law.