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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Backend Engineer - SQL, Security, Payments & Platform Architecture - **Company:** NENN LLC - **Location:** Santa Rosa Valley, CA, United States - **Experience:** Expert - **Salary:** $150,000.0 - $200,000.0 - **Contract:** Permanent contract - **Skills:** Application Programming Interfaces (APIs), Artificial Intelligence, Amazon Web Services, Application Integration Architecture, Computing Platforms, User Authentication, Microsoft Azure, Software as a Service, Cloud Computing, Cyber Security, Databases, Continuous Integration, Data Governance, Data Integrity, Relational Databases, Database Connection, Database Design, Database Storage Structures, DevOps, Disaster Recovery, Payment Systems, PostgreSQL, MySQL, Open Web Application Security, Role-Based Access Control, Standard Sql, Session Management, SQL Databases, Data Streaming, Systems Architecture, Systems Integration, Data Logging, ReactJS, Database Optimization, Software Security, Reliability of Systems, Technical Debt, Backend, Data Layers, Stripe, Data Lineage, Integration Frameworks, Codebase, Api Design, Restful APIs, Code Restructuring, Web Api - **Published:** June 21, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=5e84b198714ec00a ## About the Role Do you have experience in Systems integration?, * 5+ years backend engineering experience * Expert-level SQL (mandatory) * Strong experience with PostgreSQL/MySQL or equivalent * Proven ability to review and repair AI-generated codebases * Deep understanding of backend security principles * Experience with Stripe or equivalent payment systems * Strong API design and integration experience * Experience with system architecture and scaling applications * Familiarity with cloud infrastructure (AWS, GCP, or Azure) Preferred Qualifications * Experience with AI-assisted development environments * Experience in SaaS or operational logistics platforms * React familiarity (not required) * Experience in healthcare, veterinary, logistics, emergency response, or field operations systems * DevOps / CI/CD experience. ## Description NENN is seeking a Senior Backend Engineer to lead the stabilization, security hardening, and production readiness of an AI-assisted MVP PIMS platform. This system is being actively built with AI-generated components and requires an experienced engineer who can identify hidden risks in code, database design, and integrations, then systematically transform it into a secure, scalable, and reliable production platform. A core requirement of this role is advanced SQL expertise, including the ability to review and correct AI-generated database structures and queries. In addition, this role will own security architecture, data governance, and Stripe payment integration. The goal is to prepare the platform for public demonstration and trade show readiness by December. Core Responsibilities Architecture Ownership & System Stabilization * Audit current MVP architecture (backend, database, APIs, hosting) * Identify structural weaknesses introduced by AI-generated code * Define a scalable backend architecture (services, data flows, boundaries) * Reduce technical debt and enforce maintainable patterns * Establish environment strategy (dev / staging / production) SQL & Data Layer Ownership (Required Core Skill) * Design and normalize relational database schemas (PostgreSQL or equivalent) * Review and correct AI-generated SQL code and schema design * Optimize queries, indexing strategies, and execution plans * Identify data integrity issues (duplication, inconsistency, race conditions) * Implement audit trails and data lineage where needed * Establish backup, restore, and disaster recovery processes Security & Risk Mitigation (Critical) * Perform full application security assessment (OWASP-aligned) * Identify vulnerabilities in: * Authentication & session management * API endpoints * Database access patterns * Third-party integrations * Implement: * Role-based access control (RBAC) * Encryption at rest and in transit * Secure secrets management * Define logging, monitoring, and breach detection strategies * Ensure data privacy and compliance readiness (as applicable) Payments & Stripe Integration (Required) * Architect and implement secure Stripe integration for: * Subscriptions (if applicable) * One-time payments * Invoicing and billing workflows * Ensure PCI-safe design (no sensitive card data stored) * Handle webhook validation and idempotency correctly * Design payment state tracking in the database * Prevent double-charging, race conditions, and webhook spoofing * Build reconciliation and payment audit mechanisms API & Integration Layer * Build and maintain RESTful APIs (or equivalent architecture) * Evaluate third-party APIs for reliability and failure modes * Implement robust error handling and retry logic * Ensure system resilience under partial outages AI- Generated Code Governance (Key Requirement) * Review AI-generated backend and SQL code for correctness and safety * Identify hallucinated logic patterns, unsafe queries, or broken assumptions * Refactor AI-generated code into production-grade standards * Establish coding standards for future AI-assisted development ## Related Videos - [Navigating Growth, Scaling Challenges, and Office Expansions with David Singleton, CTO at Stripe](https://www.wearedevelopers.com/videos/100362-navigating-growth-scaling-challenges-and-office-expansions-with-david-singleton-cto-at-stripe) - [From DevOps to Scaled DevOps: How We’re Rebuilding Continuous Delivery as a Platform](https://www.wearedevelopers.com/videos/100018-from-devops-to-scaled-devops-how-we-re-rebuilding-continuous-delivery-as-a-platform) - [MySQL Protocol Features You Should Be Aware Of](https://www.wearedevelopers.com/videos/100267-mysql-protocol-features-you-should-be-aware-of) - [Postgres in the Age of AI (and Devin)](https://www.wearedevelopers.com/videos/1042-postgres-in-the-age-of-ai-and-devin) - [DevOps Maturity Check – a way to balance autonomy and alignment](https://www.wearedevelopers.com/videos/58-devops-maturity-check-a-way-to-balance-autonomy-and-alignment) - [Build Your Own Subscription-based Course Platform](https://www.wearedevelopers.com/videos/321-build-your-own-subscription-based-course-platform) ## Related Articles - [Backend Developer Salary in Germany [2023]](https://www.wearedevelopers.com/magazine/196-backend-developer-salary-in-germany-2023) - [Highest Paying Tech Companies for Developers](https://www.wearedevelopers.com/magazine/220-highest-paying-tech-companies-for-developers) - [Dev Digest 120 - Apple and peers](https://www.wearedevelopers.com/magazine/455-dev-digest-120-apple-and-peers) - [Frontend Developer Salary in Germany [2023]](https://www.wearedevelopers.com/magazine/195-frontend-developer-salary-in-germany-2023) - [Dev Digest 121 - AI goes offline](https://www.wearedevelopers.com/magazine/456-dev-digest-121-ai-goes-offline) - [What’s the Difference Between Frontend and Backend Development?](https://www.wearedevelopers.com/magazine/240-what-s-the-difference-between-frontend-and-backend-development)