Senior Software Engineer

Senior Software Engineer

A subsidiary of Publicis Groupe, Epsilon is a leading provider of multi-channel marketing services, technologies, and database solutions. At Epsilon, we do more than collect and store data. We help some of the world's biggest brands discover real opportunities inside the data types, delimiters and decimals. We are looking for a highly experienced Senior Software Engineer (7–10 years) to design, build, and scale robust backend systems using Java and Python in an Agile environment. This role has a strong emphasis on spec-driven AI-assisted development, where engineers leverage clear technical specifications and modern AI coding tools such as Cursor, Claude Code, and Kiro to accelerate development while maintaining high engineering rigor and production quality. Join us and do some truly astounding things.

Responsibilities

• Design, develop, and maintain scalable backend services using Java and Python
• Apply spec-driven AI-assisted development as a core development practice, including:
• Translating detailed functional and technical specifications into high-quality code using AI tools
• AI-assisted code generation, refactoring, and optimization with strong human validation
• Prompt-driven development aligned to explicit design and acceptance criteria
• Intelligent debugging, test generation, and code reviews using tools like Cursor, Claude Code, and Kiro.
• Build and integrate RAG-based solutions and Agentic AI workflows into enterprise systems
• Lead system design and architecture discussions
• Ensure high code quality through reviews, testing, and engineering best practices
• Collaborate with product, data, platform, and cross-functional teams
• Own and resolve complex production issues

Qualifications

• Bachelor's or Master's degree in Computer Science, Engineering, or a related field (or equivalent practical experience)
• 7–10 years of hands-on software development experience
• Strong expertise in Java and Python
• Strong backend engineering experience with Java (e.g., Spring or similar frameworks) and production-grade service development
• Experience with common Java build and delivery tooling (e.g., Maven / Gradle) and source control workflows (e.g., Git, pull requests)
• Strong Data Modeling skills and experience with relational and NOSQL databases
• Experienced working in Unix/Linux environments, including automation and scripting
• Mandatory experience with spec-driven AI-assisted development
• Practical, day-to-day usage of AI coding tools such as Cursor, Claude Code, and similar platforms
• Ability to validate, refine, and productionize AI-generated code against explicit specifications
• Mandatory hands-on experience with:
• RAG (Retrieval-Augmented Generation) architectures
• Agentic AI systems (tool-using agents, orchestration, multi-step reasoning workflows)
• Strong fundamentals in:
• Data Structures & Algorithms
• Object-Oriented Programming
• Design Patterns and System Design
• Experience building and operating backend systems in production
• Solid understanding of REST APIs, microservices, and distributed systems
• Proven ability to own problems end-to-end, including driving design, implementation, testing, and production support
• Demonstrated technical leadership (mentoring junior engineers, raising code quality via reviews, and ensuring implementations meet specifications and standards)
• Experience working in Agile / Scrum teams

Why you might stand out from other talent:

• Frontend exposure using Angular or similar frameworks
• Experience with Databricks, Spark, or large-scale data processing
• Experience with data modeling, data warehousing, and/or building ETL pipelines
• Cloud platforms (AWS / Azure / GCP) and DevOps practices
• CI/CD pipelines, Docker, Kubernetes
• Observability, monitoring, and performance tuning experience

Additional Information

Epsilon is a global data, technology and services company that powers the marketing and advertising ecosystem. For decades, we've provided marketers from the world's leading brands the data, technology and services they need to engage consumers with 1 View, 1 Vision and 1 Voice. 1 View of their universe of potential buyers. 1 Vision for engaging each individual. And 1 Voice to harmonize engagement across paid, owned and earned channels. Epsilon's comprehensive portfolio of capabilities across our suite of digital media, messaging and loyalty solutions bridge the divide between marketing and advertising technology. We process 400+ billion consumer actions each day using advanced AI and hold many patents of proprietary technology, including real-time modeling languages and consumer privacy advancements. Thanks to the work of every employee, Epsilon has been consistently recognized as industry-leading by Forrester, Adweek and the MRC. Epsilon is a global company with more than 9,000 employees around the world. Our pillars aren't just words. They're how we show up every day. People centricity: We focus on employee well-being in an environment where colleagues truly care about each other. Collaboration: We work together, support one another, and collectively achieve goals. Growth: There are endless opportunities for growth through learning, development and career advancement. Innovation: We drive progress through cutting-edge solutions and forward-thinking approaches. Flexibility: We've created a balance between work and personal life, and we encourage adaptability to solve problems creatively. Our values guide us to create value for our clients, our people and consumers. Act with integrity Work together to win together Innovate with purpose Respect all voices Empower with accountability These pillars and values are our foundation—shaping our culture, guiding our decisions, and uniting us in common purpose.

Because You Matter As an Epsilon employee, you deserve perks and benefits that put you, your family and your finances first. Our benefits encompass a wide range of offerings, including but not limited to the following: Time to Recharge: Flexible time off (FTO), 15 paid holidays Time to Recover: Paid sick time Family Well-Being: Parental/new child leave, childcare & elder care assistance, adoption assistance Extra Perks: Comprehensive health coverage, 401(k), tuition assistance, commuter benefits, professional development, employee recognition, charitable donation matching, health coaching and counseling Epsilon benefits are subject to eligibility requirements and other terms. Epsilon is an Equal Opportunity Employer. Epsilon's policy is not to discriminate against any applicant or employee based on actual or perceived race, age, sex or gender (including pregnancy), marital status, national origin, ancestry, citizenship status, mental or physical disability, religion, creed, color, sexual orientation, gender identity or expression (including transgender status), veteran status, genetic information, or any other characteristic protected by applicable federal, state or local law. Epsilon also prohibits harassment of applicants and employees based on any of these protected categories. Epsilon will provide accommodations to applicants needing accommodations to complete the application process. Please reach out to View email address on click.appcast.io to request an accommodation. For San Francisco Bay and Los Angeles Areas: Epsilon will consider for employment qualified applicants with criminal histories in a manner consistent with the City of Los Angeles' Fair Chance Initiative for Hiring Ordinance and San Francisco Police Code Sections 4901-4919, commonly referred to as the San Francisco Fair Chance Ordinance. Applicants with criminal histories are welcome to apply. Compensation Range: USD $88,900.00 - USD $165,100.00/Annually. This is the pay range the Company believes it will pay for this position at the time of this posting. Consistent with applicable law, compensation will be determined based on the skills, qualifications, and experience of the applicant along with the requirements of the position, and the Company reserves the right to modify this pay range at any time. Temporary roles may be eligible to participate in our freelancer/temporary employee medical plan through a third-party benefits administration system once certain criteria have been met. Temporary roles may also qualify for participation in our 401(k) plan after eligibility criteria have been met. For regular roles, the Company will offer medical coverage, dental, vision, disability, 401k, and paid time off. The Company anticipates the application deadline for this job posting will be 8/20/2026.