Senior Backend & AI Agent Architect (Next.js, TypeScript, Python) — Long-Term Project

Job Description: We are looking for a heavy-hitting Senior Backend Architect (8+ years of production experience) with a deep background in designing unified API integration layers and writing tools for agentic AI architectures. You will initially lead a rapid 1–2 day intensive sprint to implement an Ayrshare integration within Juliet—an AI-driven website and growth builder tool. The immediate goal is to wire up our baseline "Ship v1" social publishing spine, enabling profile connecting, scheduling, publishing, and webhook-driven monitoring across multiple brands. Following a successful kickoff, this will transition into a long-term engagement where you will lead the architecture of our broader, manifest-driven unified integration layer (building swappable provider adapters for CRM, SEO data, and messaging infrastructure). The initial codebase is already partially prepared: the database schemas, state lifecycles (draft → scheduled → published), and front-end tabs exist. Your job is to hit the ground running, act as the primary architect to build a clean, swappable PublishAdapter layer, write robust webhook ingestion engines, and cleanly expose backend capabilities as tools into our LangGraph-based AI agent layer. Key Responsibilities: Architect Swappable Integration Layers: Design and implement modular, provider-abstracted integration adapters (TypeScript/Node.js) behind strict boundaries, ensuring we avoid hard-coupled vendor lock-in. Build Agentic AI Tools: Cleanly translate complex backend API logic, schema validation, and multi-tenant connection states into autonomous, executable tools (Python/LangGraph) optimized for LLMs. Bulletproof Inbound/Outbound Data Pipelines: Implement HMAC-verified webhook ingestion, deep idempotency strategies (idempotencyKey), and rate-limit/backoff handling to eliminate data duplication or silent connection failures. Accelerated Development: Work comfortably alongside agentic developer tools (such as Claude Code and MCP workflows) to rapidly prototype, validate payloads, and push production code within tight constraints. Technical Requirements: Seniority: 8+ years of professional engineering experience architecting multi-tenant B2B SaaS platforms or complex data-integration engines. Languages: Dual-fluency in both TypeScript (Next.js/Node.js) for the backend/BFF API routes and Python for our core AI workflow layer. AI Agent Context: Practical understanding of stateful multi-agent frameworks (e.g., LangGraph, LangChain), human-in-the-loop interrupts, and dynamic tool schemas. API & Security Master: Deep expertise handling complex OAuth loops, securely managing encrypted tenant tokens (AES-256-GCM), and handling tricky platform-specific formatting quirks (carousels, media file uploads, custom CTAs). Integration & Tooling Context (Ayrshare Primitives): To help accelerate this fast-turnaround sprint, please review the following architectural primitives from the Ayrshare ecosystem: Historical post data and analytics are fully accessible via the API, allowing you to run that data through our internal modeling for tone-of-voice or performance analysis. You can check the documentation details for the History API [https://www.ayrshare.com/docs/apis/history/overview] and the Analytics API [https://www.ayrshare.com/docs/apis/analytics/overview]. Because our agent infrastructure runs on LangChain and Claude, you can leverage Ayrshare's live MCP Server [https://www.ayrshare.com/docs/additional/mcp-action-server] and their specialized Claude plugin [https://www.ayrshare.com/docs/additional/mcp-claude-code-plugin] as developer-time accelerators. We will be hooking into a data repository utilizing webhooks to push data back to our platform and reduce constant API polling. The receiver architecture can be framed around their Webhooks API [https://www.ayrshare.com/docs/apis/webhooks/overview]. All infrastructure runs on an enterprise-grade 99.99% SLA with dedicated engineering resources. All tiers include full feature access, with the exception of the vendor's Max Pack and FB Boosted ads features. Project Context: First Sprint: 1–2 days to build the baseline social publishing spine within the Juliet builder platform. Long-Term Horizon: Designing a manifest-driven, generic router to rapidly expand our API catalog across analytics, CRM routing, and complex external data endpoints. Starting Line: Detailed PRDs, database schema blueprints, and pre-mapped endpoint matrices are ready for a clean Day 0 start. If you are a high-autonomy backend engineer who builds production systems that simply don't break, and you're excited to rapidly architect the bridge between external APIs and autonomous AI agents, apply with a brief overview of your technical background.