Kastle

About Kastle Kastle is building AI operating system for consumer lending, starting with mortgage. We work with some of America's largest mortgage lenders, helping them scale their contact center and compliance operations using AI-driven voice agents. Backed by Y Combinator, Commerce Ventures, and executives from Snapdocs, Google, and WePay, we are redefining lending with AI. About the Role You’re joining at an inflection point. Our usage has grown 40x in the last 6 months and our Agent Success team is a high impact group that shapes how customers use and gain value from our product. You will partner closely with customers to guide deployments, support adoption and ensure they have the tools and insight they need to achieve meaningful outcomes. You will work cross functionally with Engineering and Sales to surface customer needs, solve challenges and help shape how our technology performs in real world environments. This role blends relationship management with hands on execution and is ideal for someone who thrives in a fast paced setting and wants to have a direct impact at a high growth company. What You’ll Do Own deployments end-to-end: scope requirements, customize agents, define success metrics, manage the roadmap, and drive customers from signed contract through full production adoption Serve as a strategic thought partner to C-suite and senior executives at major servicers and banks — shaping AI roadmaps, leading steering forums, and driving the decisions that determine how AI gets deployed across their operations Build durable executive relationships and lead high-stakes conversations around compliance risk, operational redesign, systems integration, and borrower experience transformation Translate customer requirements into production-grade AI systems — working directly with engineering to build, test, and iterate on agents handling millions of customer interactions Monitor account health through usage telemetry, surface risk early, and execute retention and expansion plays before problems escalate Partner with engineering to submit crisp, data-backed product feedback that translates customer friction into roadmap improvements Help define the playbooks, hiring bar, and operating standards that will scale the Agent Success function as Kastle grows What You'll Bring We're looking for people who have owned complex, high-stakes engagements and are ready to move from advising on strategy to being accountable for its execution. Strong candidates typically come from one of these backgrounds: Engagement Managers or Senior Consultants from top-tier management consulting firms who have led enterprise transformation programs and are ready to own outcomes rather than advise on them Technical Product Managers or Solutions Engineers who have run complex, multi-stakeholder deployments at product-focused or infrastructure technology companies and want to operate at a higher level of strategic ownership Early-stage operators or former founders who have built from zero, thrive in ambiguity, and understand what it takes to earn trust with enterprise customers Great to Have Are familiar with Agentic AI tool deployments in large organizations Have working knowledge of Customer Support processes, systems, and best practices Have experience in a high-growth startup environment Have a bachelor's degree in Science, Technology, Engineering, Math or similar fields Why join Kastle Build what banks run on: Your work powers core operations at top-25 servicers — your work directly impacts the core operations at the largest financial institutions in the world. Act like a founder: High ownership and direct input on product direction, company culture, and how the ASM function scales Learn fast: Daily exposure to the most complex AI deployments in financial services, with rapid feedback loops — see your work deployed within days Strong upside: Competitive salary, meaningful early-stage equity, and relocation support Great team: Work alongside fo

About Kastle Kastle is building AI operating system for consumer lending, starting with mortgage. We work with some of America’s largest mortgage lenders, helping them scale their contact center and compliance operations using AI voice agents. Backed by $2.3M from Y Combinator, Commerce Ventures, and executives from Snapdocs, Google, and WePay, we are redefining lending with AI. About the Role As a Forward Deployed Engineer, you’ll be the technical owner of our most important accounts. You’ll embed deeply with customers, translate messy business problems into working software, and ship AI agents on Kastle’s platform that go live in production. You’ll own outcomes end-to-end: scoping, developing, deploying, scaling, and ensuring long-term success. This is not a roadmap-bound role. You’ll work at the intersection of engineering, product, and GTM—moving fast, unblocking customers, and making Kastle indispensable. Responsibilities Build, configure, and launch AI agents on Kastle’s platform to handle real borrower workflows Write production-grade backend and full-stack code (Python, Java, TypeScript) to integrate with loan servicing systems, data sources, and telephony platforms. Scope ambiguous customer asks, prototype quickly, and iterate into stable deployments. Own reliability, performance, and security across customer environments. Act as the technical face of Kastle in key accounts, building trust through speed, empathy, and impact. Feed customer learnings back into the core product, influencing roadmap and reusable tooling. What We’re Looking For 2–5 years of software engineering experience, with real ownership of features or deployments. Strong coder with proficiency in Python, Java, or similar; comfortable building APIs and backend systems. Bias toward outcomes: you care more about unblocking customers and delivering value than perfect abstractions. Comfortable with ambiguity: able to decompose fuzzy asks, prioritize independently, and ship without a spec. Customer-centric: confident working directly with business leaders as well as engineers. Willing to relocate to SF and work 5 days a week in-office. 30% travel Nice to Have Experience building or deploying AI/ML-powered applications. Experience in highly regulated industries (finance, healthcare, etc.). Familiarity with enterprise security, networking, or infrastructure. Previous customer-facing engineering role (forward deployed, solutions engineer, etc.). Why Join Kastle? Full account ownership—from implementation to expansion. Build AI systems used by millions of borrowers. High-velocity environment with a world-class founding team. Competitive salary, equity, and relocation support.

We’re looking for an intern to start asap, in person in San Francisco. As an intern, this will be the most intense, competitive, and transformative experience of your life. You’ll work directly with the founders and a small team of exceptionally smart, driven peers who are building the operating system for consumer lending. You will: Ship real products. Touch every part of the business from customer support, growth, operations, engineering, and sales. Work directly with founders and unblock them Handle the hardest, most boring, least glamorous tasks — without flinching. Operate with extreme autonomy in an unstructured, high-paced environment. Take vague prompts like “build something that helps the company grow” and turn them into working systems — on your own, or by rallying others to help. Ideal candidate: Relentlessly resourceful Learns fast, moves faster Cares about quality Very Technical Can start next week If that’s you, email us: founders at kastle dot ai. Just tell us why you’re a fit and add “Founder Intern” in subject. Keep it short. We’ll know.

Founding Applied AI Engineer at Kastle About Kastle Kastle is building AI agents for consumer lending starting with mortgage. We work with some of America’s largest mortgage lenders, helping them scale their contact center and compliance operations efficiently using AI-driven voice agents. Backed by $2.3M from Y Combinator, Commerce Ventures, and executives from Snapdocs, Google, and WePay, we are redefining loan servicing with AI. About the Role As a Founding Applied AI Engineer, you will play a crucial role in integrating advanced AI technologies into Kastle’s platform. You’ll work on fine-tuning large language models (LLMs), designing AI workflows for highly regulated enterprises, and ensuring our AI agents deliver precise, compliant, and effective interactions. This role is ideal for an engineer who is passionate about applied AI, eager to solve real-world challenges, and excited to build the technical foundation of an early-stage AI startup. Responsibilities AI Model Integration: Fine-tune and deploy LLMs for real-time borrower interactions. Prompt Engineering: Design, test, and iterate on prompts to optimize AI performance and compliance. Custom AI Solutions: Train and implement domain-specific AI models for mortgage servicing. Scalability & Compliance: Ensure AI solutions meet regulatory standards (FDCPA, RESPA, TILA) and scale efficiently. Data Pipelines & APIs: Build robust AI-driven workflows that integrate seamlessly with loan servicing platforms. Continuous Optimization: Monitor AI performance, reduce error rates, and enhance borrower experience. What We’re Looking For 1+ years in applied AI, ML engineering, or a related role. Proficiency in Python, TensorFlow/PyTorch, and deep learning frameworks. Experience fine-tuning LLMs (Llama, GPT) and designing AI prompt workflows. Strong product mindset—ability to bridge AI capabilities with real-world mortgage servicing needs. Experience with deploying AI models into production and optimizing for speed and accuracy. Strong communication skills to collaborate with product, engineering, and compliance teams. Why Join Kastle? Build and scale AI applications that interface directly with consumers. Get to interact directly with customers on a daily basis and see them use your work in production and collect feedback. Work closely with a world-class founding team backed by top investors. High ownership and autonomy, shaping the company’s technical direction. Competitive salary, early-stage equity, and frequent company paid site visits to customers.

Founding Engineer at Kastle About Kastle Kastle is building AI operating system for consumer lending, starting with mortgage. We work with some of America’s largest mortgage lenders, helping them scale their contact center and compliance operations using AI voice agents. Backed by $2.3M from Y Combinator, Commerce Ventures, and executives from Snapdocs, Google, and WePay, we are redefining lending with AI. About the Role We’re looking for a Founding Engineer to build and optimize the Kastle platform. As an early team member, you’ll have a pivotal role in architecting and scaling our AI systems, ensuring high availability, low latency, and compliance with strict financial regulations. You’ll work closely with the founding team to design, develop, and deploy mission-critical AI applications that integrate with financial institutions. This role requires expertise in backend development and LLM Engineering—ideal for an engineer who thrives in high-impact environments. Responsibilities Architect and develop scalable backend services for AI-driven consumer lending applications. Design and implement APIs that integrate with loan servicing platforms, payment processors, and compliance systems. Optimize performance for real-time AI interactions, ensuring sub-700ms latency. Manage containerized deployments using Kubernetes to maintain high availability and reliability. Develop event-driven architectures using Python AsyncIO for parallel processing and real-time automation. Own the full development lifecycle—from designing scalable solutions to deploying and monitoring them in production. Minimum Requirements 1+ years of backend engineering experience in high-velocity environments. Expertise in Python, with strong knowledge of AsyncIO, FastAPI, or Django. Familiarity with event-driven architectures and message queues (e.g., Kafka, RabbitMQ, or Redis Streams). Strong database skills, including PostgreSQL or other relational/NoSQL databases. Excellent problem-solving skills and a passion for optimizing backend performance. Preferred Qualifications Background in AI/ML-powered systems, especially LLM applications. Previous startup experience, with a hands-on approach to problem-solving. Why Join Kastle? Build the AI operating system that large banks and lenders run on. Get to interact directly with customers on a daily basis and see them use your work in production and collect feedback. Work closely with a world-class founding team backed by top investors. High ownership and autonomy, shaping the company’s technical direction. Competitive salary, early-stage equity, and frequent company paid site visits to customers.