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Senior Lead Software Engineer, Full Stack (AI Platform & Knowledge Library) (Enterprise Platforms Technology)

Do you love building AI-powered platforms that operate at enterprise scale? Do you thrive at the intersection of applied machine learning, knowledge engineering, and production software systems? At Capital One, you'll be part of a team of makers, breakers, doers and disruptors who solve real problems and meet real customer needs.

We are seeking a Senior Lead Software Engineer to own the AI platform and knowledge infrastructure at the heart of our next-generation marketing content generation capabilities. As a Capital One Senior Lead Software Engineer, you'll have the opportunity to drive a major transformation in how we create, validate, and deliver marketing content across all channels - building the shared knowledge platform that enables AI systems to generate compliant, on-brand content at scale across the entire organization.

Enterprise Platforms Technology (EPTech) comprises many of Capital One's most important enterprise platforms. We play an essential role in establishing practices for building technology solutions across the company, while also delivering capabilities that exemplify those practices.

What You'll Do

• Design and build the Content Moderation Knowledge Library - a business-unit-scoped, RAG-backed corpus covering regulatory requirements, brand rules, claims and disclosures, and marketing context, reusable across channels and product lines

• Own the embedding search pipeline - implement and tune retrieval pipelines for grounded AI generation, including chunking strategy, embedding model selection, index refresh, and hybrid search

• Lead Prompt MLOps - treat prompts as compiled, versioned artifacts; own the evaluation loop that continuously improves generation quality against labeled production data

• Own the AI content compliance and generation platform APIs as shared capabilities across multiple engineering teams - define contracts, manage versioning, and coordinate cross-team integrations

• Design the agentic critic validation stream - deterministic parallel validators (sensitive data detection, compliance rules, claims mapping) combined with LLM-as-judge semantic validators (brand voice, coherence, substantiation)

• Lead technical design, produce architecture documents, conduct design reviews, and mentor engineers on RAG system design, eval methodology, and production AI operations

Basic Qualifications:

• Bachelor's Degree

• At least 6 years of experience in software engineering (Internship experience does not apply)

• At least 1 year experience with cloud computing (AWS, Microsoft Azure, Google Cloud)

Preferred Qualifications:

• Master's Degree

• 4+ years of experience in Python

• 4+ years of experience building and operating retrieval-augmented generation (RAG) systems

• 3 + years of experience in applied AI/ML or LLM-based systems in production.

• 3+ years of experience with vector search infrastructure (OpenSearch, Pinecone, PGvector, Weaviate, or equivalent)

• 3+ years of experience designing and owning shared platform APIs

• 2+ years of experience with AWS services (OpenSearch Service, S3, Lambda, SQS, or equivalent)

• Experience leveraging interactive AI tooling to accelerate productivity, utilizing capabilities beyond basic code completion

Capital One will consider sponsoring a new qualified applicant for employment authorization for this position.

The minimum and maximum full-time annual salaries for this role are listed below, by location. Please note that this salary information is solely for candidates hired to perform work within one of these locations, and refers to the amount Capital One is willing to pay at the time of this posting. Salaries for part-time roles will be prorated based upon the agreed upon number of hours to be regularly worked.

McLean, VA: $229,900 - $262,400 for Sr. Lead Software Engineer

New York, NY: $250,800 - $286,200 for Sr. Lead Software Engineer

Richmond, VA: $209,000 - $238,500 for Sr. Lead Software Engineer

Candidates hired to work in other locations will be subject to the pay range associated with that location, and the actual annualized salary amount offered to any candidate at the time of hire will be reflected solely in the candidate's offer letter.

This role is also eligible to earn performance based incentive compensation, which may include cash bonus(es) and/or long term incentives (LTI). Incentives could be discretionary or non discretionary depending on the plan.

Capital One offers a comprehensive, competitive, and inclusive set of health, financial and other benefits that support your total well-being. Learn more at theCapital One Careers website. Eligibility varies based on full or part-time status, exempt or non-exempt status, and management level.

This role is expected to accept applications for a minimum of 5 business days.No agencies please. Capital One is an equal opportunity employer (EOE, including disability/vet) committed to non-discrimination in compliance with applicable federal, state, and local laws. Capital One promotes a drug-free workplace. Capital One will consider for employment qualified applicants with a criminal history in a manner consistent with the requirements of applicable laws regarding criminal background inquiries, including, to the extent applicable, Article 23-A of the New York Correction Law; San Francisco, California Police Code Article 49, Sections 4901-4920; New York City's Fair Chance Act; Philadelphia's Fair Criminal Records Screening Act; and other applicable federal, state, and local laws and regulations regarding criminal background inquiries.

If you have visited our website in search of information on employment opportunities or to apply for a position, and you require an accommodation, please contact Capital One Recruiting at 1-800-304-9102 or via email at RecruitingAccommodation@capitalone.com. All information you provide will be kept confidential and will be used only to the extent required to provide needed reasonable accommodations.

For technical support or questions about Capital One's recruiting process, please send an email to Careers@capitalone.com

Capital One does not provide, endorse nor guarantee and is not liable for third-party products, services, educational tools or other information available through this site.

Capital One Financial is made up of several different entities. Please note that any position posted in Canada is for Capital One Canada, any position posted in the United Kingdom is for Capital One Europe and any position posted in the Philippines is for Capital One Philippines Service Corp. (COPSSC).