Hammed Dauda - NodeJS Developer

Overview

Senior SDET and backend engineer specializing in well-tested, safety-conscious AI-backed APIs and deterministic business logic. The strongest proven skill is building a deterministic, replayable policy engine with comprehensive boundary and safety tests as shown in backend/src/policy/rules-engine.service.spec.ts. There is little public evidence of dedicated performance or load engineering, cloud deployment hardening at scale, or external bug tracker RCAs.

Phone

Timeline

Lead Engineer · Lead

MarketEdge Advisory · Full-Time

Feb 2026 to Present 9 Months Lagos In office

Built a CRM-integrated communication platform using Twilio for high-volume client outreach. Engineered a queue-based webhook processing layer to validate and synchronize Twilio delivery statuses back to the CRM in real time, handling duplicates and out-of-order events. Implemented opt-out and suppression rules to enforce messaging compliance and designed follow-up workflows with audience segmentation.

Node JS

TypeScript

Twilio

PostgreSQL

Redis

BullMQ

React.js

Express

Senior Full-Stack Engineer · Senior

Doftwerks West Africa Limited · Full-Time

Nov 2022 to Feb 2026 3 Years 3 Months Lagos In office

Architected scalable Node.js/TypeScript backend services for an employee appraisal system, implementing JWT authentication and RBAC authorization with robust request validation and error handling. Improved processing performance using event-driven design, Bull-based queues, optimized PostgreSQL schemas with Prisma, and Redis caching. Built React 18 client features with reusable hooks and testing automation using Jest and Supertest, while containerizing and deploying to AWS.

Node JS

TypeScript

Express

React.js

PostgreSQL

Redis

Prisma

Redux Toolkit

Material UI

Docker

AWS

Amazon EC2

Jest

Supertest

Full-Stack Engineer · Middle

Wellnite Technologies · Full-Time

Oct 2019 to Nov 2022 3 Years 1 Month Partially remote

Developed a HIPAA-compliant Node.js/TypeScript backend with end-to-end encryption for sensitive patient data. Implemented OAuth 2.0 authentication with Passport.js, delivered REST and GraphQL APIs, and built real-time messaging with Socket.io. Integrated Stripe with signed webhooks, added background processing for appointment reminders, and improved API performance via query optimization and Redis caching.

Node JS

TypeScript

Express

React.js

Next.js

GraphQL

Socket.IO

Stripe

AWS

Passport.js

Redis

Full-Stack Developer · Middle

Tavia Technologies Limited · Full-Time

Jul 2019 to Oct 2022 3 Years 3 Months Lagos In office

Built Node.js/TypeScript backend services for SharePoint Online integration and developed Express.js APIs with authentication middleware, input validation, and consistent error handling. Implemented Redis caching to reduce API latency and created enterprise React/TypeScript components with Redux state management. Integrated with SharePoint APIs to support daily active users and streamlined request flows for reliability.

Node JS

TypeScript

Express

React.js

PostgreSQL

Redis

SharePoint

Redux

Projects

Wellnite Mental Health Platform

HIPAA-oriented mental health platform connecting patients with therapists using secure authenticated sessions. Implemented backend services with OAuth 2.0, encrypted/safe data handling patterns, GraphQL APIs, Socket.io messaging, and scheduled jobs for background processing. Built a Next.js frontend optimized for SEO, with server state management, data visualization, accessible UI, and PWA features for non-technical users.

TimeX

Multi-tenant time and expense management system for high-volume usage with real-time updates. Implemented backend APIs with Express and PostgreSQL, added Socket.io for live updates, and supported subscription handling via Stripe webhooks. Built a React 18 frontend with Redux Toolkit, responsive UI styling, and validated complex forms including automated overtime calculations.

iPaySuite

Enterprise payroll platform that performs complex payroll calculations and supports automated tax computation with audit logging. Built backend microservices with Express, Prisma, and queue-based processing, and integrated payment providers for subscription and payment flows. Implemented a React 18 frontend with modular architecture, Redux Toolkit state, JWT-based auth, and robust form handling for accuracy-focused workflows.

Technical skills

Languages

6

TypeScript

Node JS

Rust

JavaScript

SQL

C#

Node JS

7

Express

Passport.js

Prisma

Nest.JS

BullMQ

Sequelize

TypeORM

Rust

5

Axum

SQLx

Serde

Tracing

Tokio

Frontend

11

React.js

Next.js

Redux

Socket.IO

Material UI

Redux Toolkit

GraphQL

React Query

Tailwind CSS

Zod

Vite

DevOps

8

AWS

Amazon EC2

Docker

GitHub Actions

CI/CD

Amazon S3

Kubernetes

Docker Compose

QA

4

Jest

Supertest

Vitest

Cypress

Other

21

PostgreSQL

Redis

HIPAA

Winston

Amazon CloudWatch

AWS Lambda

.NET

React Hook Form

GitHub

QA

Recharts

Rest API

Git

Twilio

ESLint

Prettier

PostCSS

Swagger

WebSockets

State Management

PWA

Senior Backend Developer Confidence: High API Engineer

Senior backend engineer specializing in building robust, auditable AI-backed refund orchestration systems with strong safety controls. The strongest proven skill is designing a deterministic refund pipeline that isolates AI extraction from policy decisions and records replayable inputs, evidenced by backend/src/refunds/refunds.service.ts and backend/src/policy/rules-engine.service.ts. Public code does not demonstrate multi-region distributed systems, message-queue-based decoupling, or explicit performance benchmarking artifacts.

API Design

6/10

How well APIs are designed

Well-designed REST surface with pagination, filtering, consistent error shapes and an admin guard; not just autogenerated CRUD and shows deliberate API decisions around admin workflows and reply shaping.

Evidence

backend/src/admin/admin.controller.ts: Admin endpoints for list/detail/override with pagination and filters

backend/src/admin/api-key.guard.ts: ApiKeyGuard with timing-safe digest comparison for x-admin-key

backend/src/refunds/refunds.controller.ts: POST /api/refunds contract and stateless orderId handling

Data Layer & Database

6/10

Working with databases

Production-conscious data layer with Prisma migrations/seeding, idempotent seed logic, and transactional updates that guard against concurrent refunds; also a separate Rust service with SQLx that shows hand-written SQL and repository patterns.

Evidence

backend/src/refunds/refunds.service.ts: $transaction with updateMany to mark refunded items and checks to avoid double-refund

backend/prisma/seed.ts: idempotent seed logic referenced by demo fixtures and tests

secure_share_rust/src/db/file_repository.rs: sqlx queries and typed repository implementation

Scalability & Performance

5/10

Handling load and speed

Practical scalability measures - per-IP throttling, limits on page size, and concurrency-safe updates with re-evaluate-on-conflict - but no advanced distributed decoupling or measured optimizations.

Evidence

backend/package.json: dependency on @nestjs/throttler indicates per-IP throttling is used

backend/src/refunds/refunds.service.ts: MAX_SAVE_ATTEMPTS loop and retry after ItemsAlreadyRefundedError to handle concurrent duplicates

backend/test/admin.e2e-spec.ts: tests exercising pagination and pageSize limits

System Architecture

5/10

Overall system structure

Clear module decomposition (AI, policy, refunds, audit, prisma) and a deliberate pipeline (RECEIVED→EXTRACTED→VERIFIED→EVALUATED→REPLIED) enabling replayability and observability, but services run synchronously and no multi-service contract complexity is present.

Evidence

backend/src/refunds/refunds.service.ts: orchestrates the pipeline and records audit events for each stage

backend/src/policy/rules-engine.service.ts: pure, deterministic rules engine separated from DB and AI

backend/src/ai/ai.service.ts: AiService centralises timeouts, retry and validation for providers

Security & Auth

7/10

Protecting data and access

Strong security awareness: input validation, prompt-escaping and injection detection, timing-safe admin key checks, secrets validated at startup, password hashing and JWT in the Rust service; good secret and audit hygiene are evident.

Evidence

backend/src/ai/prompts/escape.ts: escaping for prompt inputs to prevent tag-closing attacks

backend/src/ai/injection-detector.ts: normalisation and heuristics for prompt-injection detection

backend/src/admin/api-key.guard.ts: timing-safe digest comparison for admin API key

Reliability & Observability

6/10

Stability and monitoring

Reliable patterns are present: timeouts and retries for AI calls, structured audit trails, graceful shutdown, robust test coverage for edge cases and error handling; lacks advanced resilience layers like circuit breakers or distributed retry policies.

Evidence

backend/src/ai/ai.service.ts and backend/src/ai/ai.service.spec.ts: 10s abortable timeout per attempt with retry and tests using fake timers

backend/src/audit/audit.service.ts: audit trail implementation used across pipeline steps

backend/src/common/all-exceptions.filter.ts: consistent JSON error shape and preservation of 4xx middleware errors

Expertise

Backend AI & LLM· Senior

Microservices & API Architecture· Middle

Node.js· Middle

Rust· Middle

Databases & Vector Storage· Senior

Technologies

Rust· since 2023 · Senior

Rest API

.NET

Nest.JS

GraphQL· since 2019

Tokio

Axum

Serde

Tracing

Prisma· since 2022

SQLx

Recommendations

Build or harden AI-assisted customer-facing backend flows that require auditable, reproducible decisioning and prompt-injection protections.
Implement deterministic policy engines and transactional refund orchestration where concurrency and idempotency are critical.
Develop secure, high-assurance Rust services that integrate with existing Node.js APIs for cryptography and file storage workloads.
Own admin tooling and observability for production services, including audit trails, structured logs and well-scoped operational tests.

Repositories

The developer's experience in this domain has been verified based on AI analysis of the following repositories:

AI-Powered-Customer-Support-Refund-System meal-beta-backend secure_share_rust

Senior Frontend Developer Confidence: High Fullstack

Fullstack engineer at a Senior level specializing in safe, auditable AI-backed backend systems and deterministic policy engines. The strongest proven skill is designing robust AI-to-business workflows and state discipline, evidenced by the AiService with timeouts/retries/abort handling (backend/src/ai/ai.service.ts) and the deterministic rules engine and its extensive tests (backend/src/policy/rules-engine.service.spec.ts). There is limited public evidence of advanced frontend component architecture, accessibility engineering and measured client-side performance tuning.

UI Component Architecture

2/10

How interface parts are built

Light evidence of small reusable client utilities and hooks but no original, deliberate component library or complex composition in the human-authored front-end files.

Evidence

AI-Powered-Customer-Support-Refund-System/frontend/src/lib/admin-key.ts

AI-Powered-Customer-Support-Refund-System/frontend/src/lib/outcome.ts

Responsive & Cross-browser

2/10

Works on all screens and browsers

Project uses modern toolchain (Vite, Tailwind) and tests mention mobile checks, but there is little custom responsive architecture or explicit RTL/i18n handling in the human-authored front-end files.

Evidence

AI-Powered-Customer-Support-Refund-System/frontend/vite.config.ts

AI-Powered-Customer-Support-Refund-System/frontend/package.json

Performance Optimization

2/10

Speed of the interface

Some sensible choices (React Query dependency, server-side concerns handled), but no measurable client-side performance artifacts, large-list virtualization or bundle-analysis evidence in the human-authored front-end files.

Evidence

AI-Powered-Customer-Support-Refund-System/frontend/package.json

AI-Powered-Customer-Support-Refund-System/frontend/src/api/client.ts

Accessibility & Semantics

1/10

Usable for everyone

Almost no explicit accessibility work visible in the human-authored front-end files; a few UX utilities exist but ARIA, keyboard handling and CI a11y checks are not present.

Evidence

AI-Powered-Customer-Support-Refund-System/frontend/src/lib/format.ts

AI-Powered-Customer-Support-Refund-System/frontend/src/lib/outcome.ts

State Management & Data Flow

5/10

Managing data in the app

Strong server-state discipline and robust data-flow patterns on the backend: deterministic rules engine, transaction-safe save logic with re-evaluation on concurrent updates, structured audit trail, and reliable AI call handling (timeouts, retries, aborts). Client-side state evidence is modest but appropriate (ApiError, apiRequest utilities and an in-memory admin key hook).

Evidence

AI-Powered-Customer-Support-Refund-System/backend/src/policy/rules-engine.service.spec.ts

AI-Powered-Customer-Support-Refund-System/backend/src/refunds/refunds.service.ts

AI-Powered-Customer-Support-Refund-System/frontend/src/lib/admin-key.ts

UX & Visual Polish

3/10

Look and feel quality

Good backend UX considerations (safe template replies, clear reply rules, audit trail) and tested edge states; front-end visual polish and bespoke UX components are limited in the human-authored client code.

Evidence

AI-Powered-Customer-Support-Refund-System/backend/src/ai/reply-templates.ts

AI-Powered-Customer-Support-Refund-System/frontend/src/lib/format.ts

Expertise

Modern Web Frameworks· Middle

Frontend AI Integration· Middle

Industries

Commerce· Senior

Technologies

JavaScript

TypeScript· since 2019 · Staff

Node JS· since 2019 · Staff

Redux· since 2019

Tailwind CSS

Next.js· since 2019

Express· since 2019

Socket.IO· since 2019

WebSockets

Winston

Git

AWS· since 2019

Docker· since 2022

Kubernetes

React.js· since 2019

Vite

React Query

Sequelize

Passport.js· since 2019

BullMQ· since 2026

TypeORM

Material UI· since 2022

PostCSS

ESLint

Prettier

Zod

Recharts

AWS Lambda

Amazon EC2· since 2022

React Hook Form

Redux Toolkit· since 2022

GitHub

Amazon S3

Amazon CloudWatch

Recommendations

Lead development of backend systems that integrate LLMs safely - design provider wrappers, timeouts, retry logic and injection detection.
Build deterministic business logic and audit trails for regulated flows such as refunds, disputes or compliance workflows.
Own admin and moderation tooling that requires robust server-state handling, transactional updates, and careful UX around escalation and review.

Repositories

The developer's experience in this domain has been verified based on AI analysis of the following repositories:

redux-react-supersquad-state-management redux-react-recipe-finder-state-management AI-Powered-Customer-Support-Refund-System

Senior QA Engineer Confidence: High SDET

Senior SDET and backend engineer specializing in well-tested, safety-conscious AI-backed APIs and deterministic business logic. The strongest proven skill is building a deterministic, replayable policy engine with comprehensive boundary and safety tests as shown in backend/src/policy/rules-engine.service.spec.ts. There is little public evidence of dedicated performance or load engineering, cloud deployment hardening at scale, or external bug tracker RCAs.

Test Automation Frameworks

7/10

Building automated tests

Well-structured test infra with isolated fixtures, an in-memory/stubbed LLM provider, database test helpers and a vitest config supporting unit and e2e suites.

Evidence

backend/test/app.ts: createTestApp bootstrap for e2e tests

backend/test/database.ts: createTestPrismaClient and truncateAll test helpers

backend/vitest.config.ts: vitest configuration for unit tests

Test Coverage & Strategy

7/10

What and how to test

Meaningful unit and boundary tests, negative-path coverage, replayable policy inputs and focused tests for safety properties and timeouts.

Evidence

backend/src/policy/rules-engine.service.spec.ts: boundaries, purity and safety property tests

backend/src/ai/ai.service.spec.ts: timeout, retry, schema validation and injection detection tests

backend/test/admin.e2e-spec.ts: API-level scenarios and negative-path checks

API & Integration Testing

7/10

Testing how parts work together

API and integration testing with real Postgres migrations/seeding in CI-like flows, Supertest-based e2e tests and tests that assert transactional behaviour and concurrency outcomes.

Evidence

backend/test/admin.e2e-spec.ts: end-to-end admin API tests using Supertest

backend/test/database.ts: test Prisma client and DB reset helpers

backend/src/refunds/refunds.service.ts: transactional save logic tested via e2e flows

Performance & Load Testing

1/10

Testing speed under load

Little or no dedicated performance/load testing; only small concurrency scenarios are covered in functional tests.

Evidence

backend/test/refunds.e2e-spec.ts: tests for concurrently submitted refund requests (concurrency functional check)

Bug Reporting & Analysis

5/10

Finding and describing bugs

Evidence of defensive fixes and root-cause handling for concurrency and input errors, but no public external bug tracker links or formal RCA artifacts in the scored files.

Evidence

backend/src/refunds/refunds.service.ts: ItemsAlreadyRefundedError and retry/re-evaluate loop to handle concurrent refunds

backend/src/common/all-exceptions.filter.spec.ts: tests exercising error shapes and client vs server error handling

CI Test Integration

5/10

Running tests automatically

CI/test scripts and vitest config present and test commands are wired into package.json, but workflow files show limited customization and one workflow file in the tree contains errors.

Evidence

backend/package.json: test, test:e2e and test:cov scripts

backend/vitest.config.ts: centralized test configuration

.github/workflows/ci.yml: CI workflow present (needs review due to reported errors)

Expertise

SDET & Test Engineering· Senior

API Testing & Contract Validation· Middle

Unit & Component Testing· Middle

Industries

Commerce· Senior

Technologies

QA

SQL

C#

Cypress

Swagger

Docker Compose

GitHub Actions

Jest· since 2022

CI/CD

Vitest

Supertest· since 2022

Recommendations

Lead development of safety-critical AI-backed APIs and the associated test and audit infrastructure.
Implement deterministic policy engines and replayable decision records for regulated workflows and payments.
Build or harden test infrastructure that exercises transactional concurrency and database migrations in CI pipelines.
Design contract and schema validation test suites (provider stubs and zod-based checks) for third-party LLM integrations.

Repositories

The developer's experience in this domain has been verified based on AI analysis of the following repositories:

redux-react-supersquad-state-management redux-react-recipe-finder-state-management AI-Powered-Customer-Support-Refund-System

Job preferences

Work permits: Nigeria
Employment type: Full-Time