Senior Backend Developer (Nest.JS - AWS - Mongo - Apollo GraphQL)
Required skills :
Nest.JS, MongoDB, AWS, Apollo GraphQL.
Company Description
At ExpiWell, we are transforming how organizations gather real-time, in-the-moment insights about human experiences. Our Experience Sampling Methodology (ESM) platform and mobile apps replace outdated survey methods, allowing organizations to capture dynamic and contextual data. Trusted by leaders in HR, Product & CX, Healthcare, and Academia, ExpiWell enables the collection of engagement, emotion, and behavior information through geofencing-triggered surveys and multimedia data capture. We aim to enhance research and promote a greater understanding of the human condition.
Position Overview :
We're seeking an experienced Senior Backend developer to modernize and extend our ExpiWell research platform API using NestJS and Apollo GraphQL, AWS and MongoDB Atlas architecture. The main server will be serving a native IOS and and Android Application as well a modern unified React Native app that is currently in development.
Key Responsibilities :
- Migrate legacy API endpoints from Express to NestJS v11 with full TypeScript typing.
- Build RESTful APIs , WebSocket gateways, and background job systems.
-Improve out AWS infrastructure to a more modern VPS. AWS certification a huge plus.
- Redesign our MongoDB architecture to better align with global customers.
- Apollo GraphQL certificate training in Parts 1 to 4. (must complete)
- Implement authentication, payment processing, and real-time messaging features.
- Write comprehensive unit tests (Jest) and maintain >
80% code coverage
Design and document APIs using Swagger / OpenAPI specifications.Review and validate AI-generated code for quality, security, and best practicesImplement AWS integrations (S3, SES) and third-party services (SendGrid, Stripe, Twilio)Required Skills
Technical Stack
Expert-level NestJS (v11+) with dependency injection, guards, interceptors, pipesAdvanced TypeScript (v5.7+) with generics, decorators, and type safety patterns
-Apollo GraphQL basic 1-4 certificate training. Free training provided by Apollo Odyssey.MongoDB with Mongoose ODM and complex aggregationsTesting : Jest, unit testing, E2E testing, test coverage strategiesRESTful API design and versioning strategiesWebSocket / Socket.IO for real-time featuresAWS Services : S3, SES, CloudWatchGit workflow with conventional commits and PR reviewsAI-Assisted Development
Experience using AI coding assistants (Claude code VSCode CLI)Ability to write effective prompts for code generationStrong code review skills to validate AI-generated codeUnderstanding of when to trust AI vs. manual implementationFamiliarity with AI-assisted testing and documentationNice to Have
React / Next.js experienceRedis for caching and distributed lockingStripe payment integrationTwilio SMS / voice integrationPuppeteer / headless browser automationSentry error monitoringDocker containerizationExperience with research / survey platformsWhat Makes You Great for This Role
You can rapidly prototype features using AI assistance while maintaining code qualityYou understand modern backend architecture (microservices, event-driven, CQRS)You write clean, maintainable code that follows SOLID principlesYou're comfortable working with large codebases and legacy migrationYou proactively write tests and documentationYou can debug complex issues across multiple servicesYou stay current with JavaScript / TypeScript ecosystem trendsProject Context
You'll be working on a research platform that powers mobile experience sampling studies. The API handles :
Survey delivery and response collectionReal-time participant messagingPayment / incentive distributionMedia upload and transcriptionGeofencing and sensor triggersAnonymous survey participationDevelopment Environment
Framework : NestJS v11 monorepo with shared librariesPackage Manager : pnpmCode Quality : ESLint v9, Prettier, TypeScriptTesting : Jest v30 with coverage reportingAI Tools : Claude Code CLI for development assistanceDeployment : AWS infrastructureHow to Apply
Submit your application with :
1. Resume highlighting NestJS and TypeScript projects
2. GitHub and profile
3. Brief description of your experience with AI coding tools.
What We Offer :
Fully remote, flexible work setupSupportive, collaborative global teamOpportunities for long-term growth and increased responsibility