Backend Systems Engineer | Full-Stack Developer

William Lyons

I’ve led the architecture and delivery of high-scale backend platforms and full-stack systems across Python, Node.js, and .NET, building resilient cloud-native solutions on AWS and Azure. I operate at the intersection of engineering, product, and design-turning ambitious ideas into robust, production-grade systems that scale with confidence.

Tech Stack

ReactNext.jsTypeScriptJavaScriptReduxReact QueryTailwind CSSNode.jsExpressNestJSPythonFastAPIDjangoMongoDBPostgreSQLMySQLSupabaseAmazon Web ServicesGoogle Cloud PlatformDockerFirebaseGitGitHubOpenAILangChainAzureC#.NETASP.NET CoreHugging FaceAngular

Certifications

AWS Certified Cloud Practitioner

Expires July 2028

AWS Certified AI Practitioner

Expires November 2028

Microsoft Certified: Azure Fundamentals

AWS Agentic AI Demonstrated

Expires January 2027

Projects.

xFigura — Generative AI Platform project preview

xFigura — Generative AI Platform

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Public product experience for an AI text, image, and 3D generation platform: clear positioning for creative professionals, fast marketing pages, and a cohesive story around multimodal generative tooling.

Next.jsGenerative AIPythonFastAPIThree.jsMachine Learning
MoeGo project preview

MoeGo

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Marketing and product storytelling for an all-in-one pet business platform—scheduling, operations, payments, and customer experience—tailored to mobile groomers, salons, boarding, daycare, and scaling multi-location operators.

ReactPythonDjangoNode.jsPostgreSQLOpen AI
Short Circuit Electronics project preview

Short Circuit Electronics

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Bold, dark-themed site for a 30-year car audio and electronics shop in Staunton, VA. Custom audio visualizer animation, 9-project gallery, and conversion-focused design built to drive phone calls.

Next.jsTypeScriptTailwind CSSLocal SEOCustom Animations
Mosaic Ridge Client Portal project preview

Mosaic Ridge Client Portal

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Full-stack client dashboard with authentication, Stripe Connect subscription billing, automated weekly analytics email reports, and a cron-based pipeline for site performance summaries. Real paying customers use this system.

Next.jsNode.jsSupabaseStripe ConnectResendVercel
BorrowWorks project preview

BorrowWorks

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Fintech-focused platform and services presence centered on smart data, decision science, ACH processing, and cloud architecture for banks, lenders, and fintech partners.

PythonC#FastAPIASP.NET CoreEntity FrameworkMicrosoft AzureFintech
StrongSuit project preview

StrongSuit

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Legal AI platform for litigators featuring legal research with citations, contract redlining, litigation drafting, and discovery workflows built for lawyer-in-the-loop execution.

Legal AIPythonDjangoRAGAmazon Web ServicesPostgreSQLRedis

Experience.

2025202420232011

August 2024 - Present

Freelance

Senior Software Engineer

Build and ship production software for client projects, from architecture and API design through deployment and long-term maintenance.

  • Architect end-to-end systems using NestJS, .NET and Python services with clear domain boundaries, API versioning, and asynchronous job processing.
  • Deliver secure integrations, role-based access controls, observability, and CI/CD pipelines to support reliable production operations.
  • Partner directly with stakeholders to scope features, prioritize delivery, and translate product requirements into maintainable backend platforms.
PythonNode.jsNestJS.NETPostgreSQLRedisDockerAWSGitHub Actions

July 2022 - August 2024

Borrow Works

Founding Engineer

Helped build the core platform from the ground up for equipment rental and asset operations, establishing backend architecture and engineering standards.

  • Implemented core rental lifecycle services (inventory, reservations, billing workflows, and notifications) using a service-oriented NestJS architecture.
  • Designed Python-based background workers for reconciliation, reporting, and operational automation across finance and ops data pipelines.
  • Set up deployment workflows, metrics, and alerting to improve release confidence and reduce incident resolution time.
Node.jsNestJSPythonPostgreSQLRedisAWSDockerTerraform

September 2020 - September 2022

Brex

Software Engineer

Contributed to financial product infrastructure supporting card, spend, and internal operations workflows with an emphasis on reliability and developer velocity.

  • Built and maintained backend APIs and internal tooling to support transaction lifecycle events, controls, and compliance-sensitive workflows.
  • Improved service performance and resiliency through profiling, queue-based processing, and better failure handling patterns.
  • Worked closely with product and data teams to ship features with clear ownership, measurable outcomes, and production-grade monitoring.
PythonNode.jsNestJSPostgreSQLKafkaRedisKubernetesAWS

August 2014 - August 2020

Relativity

Software Engineer

Developed backend systems for legal and compliance workflows, focused on secure data handling, workflow automation, and enterprise-scale stability.

  • Delivered API and service features for document and case-management workflows with strong auditability and permission controls.
  • Built Python and Node.js services for ingestion, transformation, and asynchronous processing of large data volumes.
  • Collaborated across product and platform teams to modernize architecture and reduce operational complexity in core services.
PythonNode.jsNestJSSQL ServerPostgreSQLRabbitMQDockerAzure

September 2009 - August 2013

Imaginary Landscape

Software Developer

Built custom web and backend solutions across client engagements, translating varied business requirements into production-ready applications.

  • Developed backend APIs and integration endpoints for content, commerce, and operational systems across multiple client accounts.
  • Implemented automation scripts and services in Python to streamline recurring operational and data tasks.
  • Contributed to deployment and support processes, improving release consistency and post-launch maintainability.
PythonNode.jsNestJSPostgreSQLMySQLLinuxNginxGit

October 2002 - September 2009

Contegix

Linux System Administrator

Managed Linux-based hosting environments and platform operations, building a strong foundation in reliability, automation, and production support.

  • Administered servers, networking, backups, and security hardening for customer-facing applications and hosted services.
  • Automated system maintenance and monitoring tasks using Python and shell tooling to reduce manual operational load.
  • Partnered with engineering teams to troubleshoot production incidents and improve platform uptime and performance.
PythonNode.jsLinuxBashNginxApacheMySQLMonitoring

Connect.

Feel free to reach out to plan your next project.