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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Backend Engineer - ChainIT Pay - **Company:** ChainIT Inc. - **Location:** United States (Remote available) - **Experience:** Expert - **Salary:** $80,000.0 - $115,000.0 - **Contract:** Permanent contract - **Skills:** ASP.NET, Java (Programming Language), JavaScript (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Amazon Web Services, Amazon S3, Audit Trail, Automation of Tests, Microsoft Azure, Biometrics, C Sharp (Programming Language), Cloud Computing, Code Coverage, Code Review, Databases, Command-Query Responsibility Segregation (Software Development), Relational Databases, Payment Systems, Middleware, Identity and Access Management, Key Management, PostgreSQL, MongoDB, Node.Js, Object-Relational Mapping, PCI Data Security Standards, Query Optimization, RabbitMQ, Ruby on Rails, Redis, PM2, Swagger, Next.js, SQL Databases, Data Streaming, Systems Integration, Strategies of Testing, TypeScript, Management of Software Versions, Openapi, AWS Cdk, Apache Yarn, Spring-boot, Indexer, Backend, Kotlin, Stripe, Integration Tests, Kubernetes, Sentry, Apache Kafka, Graphql, Web3.js, Route53, Api Design, NestJS, Amazon Simple Queue Service (SQS), Monolithic Repository, Microservices - **Published:** May 14, 2026 - **Apply:** https://www.indeed.com/viewjob?jk=632c5a674bd9833e ## About the Role Do you have experience in SQL databases?, * 5+ years of production backend engineering, with 3+ years in TypeScript or another strongly-typed OO language (Java, C#, Kotlin) * 2+ years of NestJS, or deep experience in an equivalent DI-first framework (Spring Boot, ASP.NET Core, Ruby on Rails) * Strong relational database fundamentals: schema design, migrations, indexing, query tuning. Postgres preferred. * Production experience with at least one queue/streaming system (RabbitMQ, SQS, Kafka, NATS) * Comfortable operating in AWS: S3, IAM, Secrets Manager, ECR, and Kubernetes (EKS) * Demonstrable habit of writing testable code. You know what good test coverage looks like even if prior codebases lacked it. * Experience working in a monorepo (Nx, Turborepo, Bazel, Lerna, or similar) * Payment industry experience - familiarity with payment rails, processors (e.g. Paysafe, Stripe, Plaid), or regulated payment flows (ACH, card-present, disbursements). We already integrate with Plaid and Paysafe; prior exposure here shortens the learning curve. * Prior work in a regulated industry (FinTech, HealthTech, GovTech, gaming), * Back-end development: 3 years (Required) * Next.js: 2 years (Required) * AWS: 3 years (Required) ## Description * ChainIT Pay - PayFac/ISO payment processing, merchant onboarding, disbursements, and regulated payment flows * Pactvera - court-enforceable biometric smart agreements (1,000+ business rules) * Sportafi - NIL payment automation and Title IX reporting for college athletics * Age App - privacy-first age verification (no PII stored) * ChainITX - physical-to-digital asset tokenization (ERC-721) * Touch Audit - HIPAA-aligned zero-knowledge audit trails * ChainIT SDK - launched at Consensus 2025 Customers include U.S. banks, mortgage lenders, and government agencies. Our philosophy: Truth over Trust - nothing is assumed, everything is verified. The Role You will own and evolve the payments-focused backend services that power ChainIT Pay - our PayFac/ISO payment processing platform. Your work sits at the intersection of regulated payment flows, merchant lifecycle management, and the shared ChainIT platform layer. This is not a greenfield role. You will inherit a production codebase that: * Runs 25+ Nx-managed microservices using CQRS + hexagonal architecture * Persists audit-grade records to Amazon QLDB (immutable ledger) alongside per-service Postgres * Integrates with ~40 external systems including payment processors and rails (Paysafe, Plaid, ACH networks), AWS services (Cognito, KMS, S3), identity providers (Incode, IDScan, Regula), and more * Communicates over dual transport (HTTP/REST + RabbitMQ quorum queues) Unlike our product-assigned Full Stack Engineers, this role is payments-platform-first: you serve ChainIT Pay and its downstream consumers, ensuring payment processing, merchant onboarding, disbursements, and compliance flows are reliable, auditable, and scalable. What You Will Own * Architecture and implementation decisions across ChainIT Pay backend services (candidates include: payment processing, merchant onboarding, disbursement orchestration, settlement reconciliation, transaction monitoring, subscriptions, reports, notifications - scope assigned at onboarding) * CQRS command/query handlers, domain aggregates, and RabbitMQ event flows for payment lifecycle events * TypeORM schema design, migrations, and indexing for per-service Postgres databases * QLDB ledger integration for immutable audit records (Validated Data Tokens) * API versioning and OpenAPI / AsyncAPI contracts consumed by our new AI-Agent Contracts Hub - the cross-org source of truth for AI coding agents working across every BIT codebase * Integration with payment processors and rails (Paysafe, Plaid, ACH, card-present, disbursement networks) - maintaining, extending, and hardening these integrations * Test strategy rollout: schema-lockfile diff runners, service-level integration tests against real Postgres, contract tests * Code review for Full Stack Engineers on product teams whose UIs consume your services * Production on-call rotation (EKS / Helm / PM2 cluster), * Amazon QLDB or other immutable ledger systems (Immudb, Azure Confidential Ledger) * Web3 integrations: ethers.js, Alchemy, AWS KMS signers, ERC-721 / ERC-20 interaction * Experience introducing a test framework into a production codebase with little or no existing coverage * Biometric / identity verification domain (IDV vendors, liveness detection, eKYC) * OpenAPI / AsyncAPI tooling and contract-first API design * PayFac/ISO operations - merchant underwriting, sponsor bank relationships, PCI-DSS compliance, chargeback management * AML/KYC/KYB compliance engineering - building or integrating transaction monitoring, sanctions screening, or suspicious activity reporting systems Stack You Will Work With * Language / Runtime: TypeScript 5.1, Node.js 20.15, Yarn 1.x * Framework: NestJS 10 (CQRS, Microservices / RMQ, TypeORM, Mongoose, GraphQL, Bull, Swagger) * Monorepo: Nx 16 - 25+ apps + shared libraries * Persistence: TypeORM 0.3 + Postgres (per-service DB), Mongoose 6, Amazon QLDB * Messaging: RabbitMQ (quorum queues), Redis, Bull * Cloud / Infra: AWS SDK v3 (S3, Cognito, Rekognition, KMS, SES v2, SNS, Route 53), AWS CDK, EKS + Helm, PM2 cluster in containers * Observability: pino + Sentry * Testing: Jest 29 (currently under-utilized - you will help change that) * Auth: JWT + Passport + custom auth middleware * Web3: ethers 6, Alchemy SDK, AWS KMS Web3 signers * Payments: Paysafe, Plaid, ACH processing, card-present integrations Why This Role Is Worth Your Time * Real payments, real regulation. You'll work with live payment rails, ACH flows, disbursement orchestration, and merchant onboarding - not sandboxed demos. * You install the safety net. A production platform with zero test coverage is a rare opportunity to define what "done" means going forward. * Platform leverage. ChainIT Pay rides on the shared platform. One well-designed change compounds across the entire product portfolio. * AI-native engineering. We are building an agent-consumable contracts hub so AI coding agents across the org always ground in one current, versioned source of truth. You will help shape it. * Patent-backed technology. 14+ U.S. patents on identity, tokenization, and verification primitives - you will be implementing the real thing, not a wrapper. ## Related Videos - [Nest.js - TypeScript in the backend can also be clean](https://www.wearedevelopers.com/videos/1033-nest-js-typescript-in-the-backend-can-also-be-clean) - [Meet Your New BFF: Backend to Frontend without the Duct Tape](https://www.wearedevelopers.com/videos/682-meet-your-new-bff-backend-to-frontend-without-the-duct-tape) - [Reducing LLM Calls with Vector Search Patterns - Raphael De Lio (Redis)](https://www.wearedevelopers.com/videos/1714-reducing-llm-calls-with-vector-search-patterns-raphael-de-lio-redis) - [Streaming AI Responses in Real-Time with SSE in Next.js & NestJS](https://www.wearedevelopers.com/videos/1630-streaming-ai-responses-in-real-time-with-sse-in-next-js-nestjs) - [Next, Nest, Nuxt… Nust?](https://www.wearedevelopers.com/videos/421-next-nest-nuxt-nust) - [Build and Deploy a Fullstack App with Open Source Tooling](https://www.wearedevelopers.com/videos/775-build-and-deploy-a-fullstack-app-with-open-source-tooling) ## Related Articles - [What’s the Difference Between Frontend and Backend Development?](https://www.wearedevelopers.com/magazine/240-what-s-the-difference-between-frontend-and-backend-development) - [Backend Developer Salary in Germany [2023]](https://www.wearedevelopers.com/magazine/196-backend-developer-salary-in-germany-2023) - [Frontend Developer Salary in The UK](https://www.wearedevelopers.com/magazine/233-frontend-developer-salary-in-the-uk) - [React Developer Salary [2023]](https://www.wearedevelopers.com/magazine/198-react-developer-salary-2023) - [Highest Paying Tech Companies in Europe](https://www.wearedevelopers.com/magazine/162-highest-paying-tech-companies-in-europe) - [The 7 Most Popular Backend Frameworks for Developers](https://www.wearedevelopers.com/magazine/403-the-7-most-popular-backend-frameworks-for-developers)