Principal Engineer, API & MCP Platform

Babel Street•Reston, VA

1d•Hybrid

About The Position

Babel Street is the trusted technology partner for the world’s most advanced identity intelligence and risk operations. We deliver advanced AI and data analytics solutions providing unmatched, analysis-ready data regardless of language, proactive risk identification, 360-degree insights, high-speed automation, and seamless integration into existing systems. Babel Street empowers government and commercial organizations to transform high-stakes identity and risk operations into a strategic advantage. The actionable insights we deliver safeguard lives and protect critical assets around the world. Babel Street is headquartered in Reston, Virginia, with regional offices in Boston, MA and Cleveland, OH, and international offices in Australia, Canada, Israel, Japan, and the U.K. For more information, visit www.babelstreet.com. Role Summary We are seeking a Principal Engineer to lead Babel Street’s API and MCP platform strategy and delivery as we evolve toward an AI-native, agent-driven platform. This is a hands-on, senior technical leadership role responsible for defining and delivering API-first platform capabilities that enable both developers and AI agents to interact with Babel Street’s services. You will lead the design and implementation of semantic APIs, Model Context Protocol (MCP) integrations, and context-aware service patterns that power next-generation intelligence workflows. This role requires a finger-on-keyboard engineer who can both define direction and deliver foundational systems. You will partner closely with AI, Data, and Platform teams to ensure Babel Street’s APIs and services are consistent, discoverable, scalable, and optimized for agentic workflows. You will work in close partnership with the Architecture function to align on long-term technical direction, ensuring API and MCP platform decisions are consistent with the company’s broader architectural vision while maintaining a strong focus on execution and delivery. This is a hybrid role working out of either our Reston, VA or Somerville, MA office. Full remote may be considered. Why This Role Matters This role will be instrumental to Babel Street’s AI-native technology strategy. The API and MCP platform will serve as the interface layer between data, AI, and product capabilities, enabling agents, developers, and systems to interact seamlessly. This is a high-impact, senior technical leadership role with broad influence across the organization and the opportunity to shape the future of Babel Street’s platform. The position spans four core domains: API Platform & Strategy You will define and lead Babel Street’s API-first platform strategy, establishing consistent patterns for service design, versioning, discoverability, and governance. You will help evolve the platform toward agent-ready APIs, ensuring services are consumable by both human developers and AI agents. You will establish standards for API consistency, reliability, and performance across the organization. You will also work closely with product and engineering teams to ensure APIs are designed as first-class platform capabilities, not just service interfaces. MCP & Agent Integration You will lead Babel Street’s Model Context Protocol (MCP) strategy and implementation, enabling agents and AI systems to interact with services in a standardized and scalable way. This includes defining patterns for: MCP service exposure Tool and service discovery Agent-to-service communication Context-aware interactions You will partner closely with AI and platform teams to enable agent-native workflows across the organization. Semantic APIs & Agent-Ready Interfaces You will lead the design of semantic, agent-friendly APIs, where documentation becomes a first-class interface for AI-driven systems. This includes defining standards for: API descriptions optimized for agents Schema consistency and semantic modeling Tool and service discoverability API documentation optimized for agent consumption You will establish best practices for documentation-as-code, ensuring APIs are designed for both developers and AI systems. Context Management & Runtime Patterns You will define patterns for context-aware APIs and services, including: Context management and retrieval Context caching Session and state management Memory-aware service interactions You will help design scalable context-aware systems leveraging technologies such as Vertex AI Context Caching and related frameworks.

Requirements

10+ years of software engineering experience
Experience operating at Principal Engineer or Staff+ level
Strong hands-on experience building distributed systems
Experience designing and building API-first platforms
Experience with cloud-native architectures (GCP preferred)
Experience building developer platforms or service-oriented architectures
Strong system design and architectural thinking skills
Proven ability to lead cross-team technical initiatives

Nice To Haves

Hands-on work with Google Cloud Platform (GCP)
Familiarity with Vertex AI Agent Engine
Background in ADK and reasoning frameworks such as LangChain
Understanding of the Model Context Protocol (MCP)
Exposure to data warehouse technologies like BigQuery and Snowflake
Knowledge of Apigee or similar API gateway solutions
Proven ability to design semantic APIs for AI or agent-driven use cases
Experience managing context or building memory systems
Development of agent-based architectures or orchestration frameworks
Exposure to Anti-Gravity

Responsibilities

Partner closely with Architecture to define and lead Babel Street’s API and MCP platform strategy
Design and deliver semantic, agent-ready APIs
Establish MCP standards and implementation patterns
Define context management patterns for agent workflows
Partner with AI and Data teams to enable agent-native architectures
Establish API governance and platform standards
Build foundational frameworks and reusable components
Provide hands-on technical leadership and mentorship
Partner with Google and other vendors on platform capabilities
Drive adoption of API and MCP standards across engineering teams

Benefits

Health Benefits: Babel Street covers 85-100% monthly premium costs for Medical, Dental, Vision, Life & Disability insurances – for you and your family!
Retirement Plans: Babel Street offers both a Traditional and Roth 401(K) with a very competitive match.
Unlimited Flexible Leave: We trust our employees to manage their own time and balance their personal and work lives.
Holidays: Babel Street provides employees with 12 paid Federal Holidays
Tuition Reimbursement: We are committed to investing in our employees. One way we do that is with our Tuition Reimbursement Program for continuing education.

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