Senior Software Engineer – MCP & AI Platform

InApp; United States; Hybrid; USD 140,000 - 190,000; Full time

Job summary

InApp is seeking a Senior Software Engineer to design and build the MCP and AI Platform backend. You will craft MCP server components, API schemas, and secure auth layers, while ensuring safe integration with LLMs and enterprise security standards.

You will own API versioning, observability, and circuit-breaker strategies, collaborating with InfoSec to meet WAF and private VPC requirements in a fast-moving enterprise space.

Qualifications

• 4+ years of professional software engineering experience building production backend systems.
• Direct experience designing and implementing MCP servers – shipped MCP integration in production or active use.
• Strong proficiency in Node.js or TypeScript; familiarity with Python or Java is a plus.
• Experience with AWS Lambda, API Gateway, VPC, Secrets Manager, and CloudWatch.
• Solid understanding of REST API design, OpenAPI/Swagger specifications, and API versioning strategies.
• Experience with OAuth 2.0 flows and API Key management.
• Clear understanding of how LLMs consume tool definitions and how tool description quality affects agent behavior.
• Strong security instincts: authentication vs authorization and credential exposure considerations.

Responsibilities

• Design and implement the Client Pulse MCP server exposing tools for approvals, billing, and workforce events via REST APIs.
• Define tool schemas, descriptions, and input/output contracts for LLMs.
• Implement the auth layer with API Key, OAuth 2.0 client credentials, and per-tenant isolation using Secrets Manager.
• Build a guardrail layer to prevent unsafe AI-triggered mutations.
• Implement response normalization for paging large payloads within context limits.
• Own the tool versioning strategy to avoid breaking deployments.
• Integrate MCP server logging with CloudWatch and maintain durable audit trails.
• Add circuit breaker and retry logic for VMS paths (API Gateway → Lambda → Direct Connect).
• Collaborate with InfoSec to meet enterprise security requirements including WAF, private VPC, PEN tests.
• Participate in architecture reviews and evolve the Client Pulse API Platform.

Skills

MCP server design

Node.js / TypeScript

Security mindset

REST API design

OAuth 2.0 flows

Tools

AWS Lambda

API Gateway

VPC networking

Secrets Manager

CloudWatch

SNS/SQS

Direct Connect

OpenAPI/Swagger

Redis

ElasticSearch

Slack Bolt SDK

Bot Framework

Java / Spring Boot

Job description

Senior Software Engineer – MCP & AI Platform

Experience : 4-8 years Project Location(s) : Hybrid/Remote

Notice Period: Immediate to 10 days

What You Will Do

• Design and implement the Client Pulse MCP server exposing tools for approvals, billing, and workforce events, mapped to our existing REST API (/v1/approvals, /v1/billings, /v1/events).
• Define tool schemas, descriptions, and input/output contracts that are precise enough for LLMs to invoke correctly without hallucination.
• Implement the auth layer: API Key injection, OAuth 2.0 client credentials flow, and per-tenant credential isolation using AWS Secrets Manager.
• Build the confirmation and safety guardrail layer for write tools to prevent unsafe AI-triggered mutations.
• Implement response normalization so complex, paginated API payloads are reshaped into LLM-friendly summaries without exceeding context window limits.
• Design and own the tool versioning strategy so breaking API changes never break deployed agents.
• Integrate MCP server logging with Amazon CloudWatch and ensure every tool invocation produces a durable, queryable audit trail.
• Implement circuit breaker and retry logic for the VMS call path (API Gateway → Lambda → AWS Direct Connect → on-prem VMS).
• Collaborate with InfoSec to ensure the MCP server meets enterprise security requirements including WAF compliance, private VPC deployment, and PEN test remediations.
• Participate in architecture reviews and contribute to the evolution of the Client Pulse API Platform.

What You Bring

Required:

• 4+ years of professional software engineering experience building production backend systems.
• Direct experience designing and implementing MCP servers – you have shipped at least one MCP integration that is in production or active use.
• Strong proficiency in Node.js or TypeScript; familiarity with Python or Java is a plus.
• Experience with AWS Lambda, API Gateway, VPC networking, Secrets Manager, and CloudWatch.
• Solid understanding of REST API design, OpenAPI/Swagger specifications, and API versioning strategies.
• Experience with OAuth 2.0 flows (client credentials, on-behalf-of) and API Key management.
• Clear understanding of how LLMs consume tool definitions and how tool description quality affects agent behavior.
• Strong security instincts: you know the difference between authentication and authorization, and you think about credential exposure before writing the first line.

Preferred:

• Experience building integrations with Microsoft Bot Framework or Slack Bolt SDK.
• Familiarity with enterprise SaaS platforms (Workday, SAP Fieldglass, ServiceNow, or similar VMS/HCM systems).
• Experience with the approval outbox pattern or event-driven architectures using SNS/SQS.
• Exposure to Redis caching and ElasticSearch in a production context.
• Background in workforce management, procurement, or enterprise HR technology.

Tech Stack

• MCP: Model Context Protocol (Anthropic spec)
• Runtime: Node.js / TypeScript (MCP server layer)
• Cloud: AWS (Lambda, API Gateway, VPC, Secrets Manager, CloudWatch, SNS/SQS, Direct Connect)
• Backend: Java / Spring Boot / PostgreSQL (on-prem VMS – you integrate with it, not build it)
• Auth: OAuth 2.0, API Key
• Observability: Amazon CloudWatch
• Channels: Microsoft Teams (Bot Framework), Slack (Bolt SDK)

WhyThis Role

• You own the layer. MCP architecture is finalized. You are not joining a committee – you are shipping the server.
• Real enterprise scale. Client manages billions in workforce spend. The tools you build will be used by managers at Fortune 500 companies to approve real workforce actions.
• Early in a fast-moving space. MCP is months old as a production standard. You will be defining best practices, not following them.
• Strong technical foundation. The API Platform, auth model, observability stack, and security architecture are already production-grade. You are adding a layer on top of something that works.

About Us

• Our Purpose & Values
• Leadership
• Our Approach
• Life@InApp
• Our History
• CSR