Senior MERN Stack Engineer

Ajackus; Mumbai; On-site; INR 900,000 - 1,400,000; Full time

Job summary

Ajackus is seeking a hands-on Senior Full Stack Engineer to own a Talent Development Platform end-to-end. The role spans frontend and backend development, database design, security, and production support for a multi-tenant B2B SaaS product.

You will work across requirements, architecture, testing, deployment, and observability, ensuring scalable, secure solutions with RTL language support and AI-assisted features where appropriate.

Qualifications

• 5–9 years in full-stack software development.
• At least 2 years as Senior/Lead Engineer owning a multi-tenant B2B SaaS app.
• Strong hands-on with React and TypeScript.
• Proficient in Node.js backend development and API design.
• Strong PostgreSQL SQL skills including design, migrations, indexing and performance.
• Experience implementing authorization and tenant isolation.
• Experience building REST APIs, webhooks, jobs, and third-party integrations.
• Strong automated testing across unit, integration and security.
• Experience with Git, GitHub, Docker, and CI/CD operations.
• Cloud deployments, monitoring, observability, and incident support.
• Knowledge of multi-tenant SaaS security, idempotency and secret management.
• Ability to evaluate AI-assisted code for correctness and security.
• Independence and ownership from requirements to production.

Responsibilities

• Develop, maintain, and enhance frontend and backend applications using React, TypeScript, Node.js, Drizzle ORM, and PostgreSQL.
• Own PostgreSQL database design and production readiness including schema changes, indexing, transactions, and RLS.
• Build secure REST APIs, backend services, validation, authorization workflows, and multi-tenant functionality.
• Develop enterprise integrations including inbound webhooks, identity integrations, bulk imports, background jobs, file storage, and notifications.
• Maintain and enhance product experiences for employees, managers, HR teams, and executives.
• Develop features across competency management, assessments, development plans, evidence tracking, coaching, reassessment, and workforce intelligence.
• Manage CI/CD operations, deployment workflows, and release readiness.
• Implement observability, health checks, structured logging, error handling, and production diagnostics.
• Ensure complete English and Arabic language support including RTL layouts.
• Implement AI-powered features with structured outputs, usage controls, validation, auditability, and safe failure handling.
• Review and validate AI-generated code before merging or deploying.
• Write and maintain automated tests covering business logic, authorization, DB operations, tenant isolation, and critical user journeys.
• Troubleshoot production issues, investigate regressions and bottlenecks, perform root-cause analysis.
• Collaborate with Integration Lead to develop reusable integration capabilities and client-specific enhancements.
• Maintain clean architecture, promote code reuse, and prevent technical debt.

Skills

React

TypeScript

Node.js

PostgreSQL

SQL

Authorization

Tenant isolation

REST APIs

Webhooks

Background jobs

Integrations

Automated testing

Git

GitHub

Docker

CI/CD

Cloud deployments

Monitoring

Observability

Security

Multi-tenant SaaS security

AI-assisted development

Ownership

Arabic RTL

B2B SaaS

Tools

Drizzle ORM

PostgreSQL

Docker

Job description

We are looking for a Senior Full Stack Engineer to take end-to-end ownership of an enterprise Talent Development Platform. The role involves building and maintaining scalable frontend and backend applications, managing production databases, developing enterprise integrations, and ensuring application security, performance, and reliability.

You will work across the entire product lifecycle, from requirement analysis and architecture to development, testing, deployment, and production support. The ideal candidate has hands‑on experience owning a live, multi‑tenant B2B SaaS application and can balance rapid feature delivery with technical quality, security, and maintainability.

Key Responsibilities

• Develop, maintain, and enhance frontend and backend applications using React, TypeScript, Node.js, Drizzle ORM, and PostgreSQL.
• Own PostgreSQL database design and production readiness, including schema changes, migrations, indexing, transactions, performance optimization, and row‑level security (RLS).
• Build secure REST APIs, backend services, validation mechanisms, authorization workflows, and multi‑tenant functionality.
• Develop enterprise integrations, including inbound webhooks, identity integrations, bulk employee and organization imports, background jobs, file storage, and notification services.
• Maintain and enhance product experiences for employees, managers, HR teams, and executives.
• Develop features across competency management, assessments, development plans, evidence tracking, coaching, reassessment, and workforce intelligence.
• Manage day‑to‑day application CI/CD operations, deployment workflows, and release readiness.
• Implement observability, health checks, structured logging, error handling, and production diagnostics.
• Ensure complete English and Arabic language support, including right‑to‑left (RTL) layouts wherever applicable.
• Implement AI‑powered features with structured outputs, usage controls, validation, auditability, and safe failure handling.
• Review and validate AI‑generated code before merging or deploying it to production.
• Write and maintain automated tests covering business logic, authorization, database operations, tenant isolation, and critical user journeys.
• Troubleshoot production issues, investigate regressions and performance bottlenecks, and perform root‑cause analysis.
• Collaborate with the Integration Lead to develop reusable integration capabilities and implement client‑specific product enhancements.
• Maintain clean architecture, promote code reusability, and prevent unnecessary technical debt or duplication of models and workflows.

Required Skills & Experience

• 5–9 years of experience in full‑stack software development.
• At least 2 years of experience as a Senior or Lead Engineer with significant ownership of a production‑grade, multi‑tenant B2B SaaS application.
• Strong hands‑on experience with React and TypeScript.
• Proficiency in Node.js backend development and API design.
• Strong knowledge of PostgreSQL and SQL, including database design, schema migrations, indexing, transactions, and performance troubleshooting.
• Practical experience implementing authorization, tenant isolation, and database‑level or policy‑based access controls.
• Experience building REST APIs, webhooks, scheduled tasks, background jobs, and third‑party integrations.
• Strong automated testing practices across unit, integration, security, and database‑backed workflows.
• Experience with Git, GitHub, Docker, and day‑to‑day CI/CD operations.
• Working knowledge of cloud deployments, application monitoring, observability, production troubleshooting, and incident support.
• Understanding of multi‑tenant SaaS security, idempotency, auditability, and secure secret management.
• Ability to critically evaluate AI‑assisted and AI‑generated code, with a strong focus on correctness, security, and maintainability.
• Ability to work independently and take ownership of features from requirements through deployment and production support.

Good to Have

• Experience with Drizzle ORM and PostgreSQL Row‑Level Security (RLS).
• Experience with MySQL‑to‑PostgreSQL migration or production database cutovers.
• Background in B2B or enterprise SaaS product development.
• Experience in HR technology, talent management, assessments, LMS/LXP, or workforce platforms.
• Familiarity with Microsoft Entra ID, OAuth 2.0, OIDC, or SAML‑based authentication.
• Experience building multilingual applications, particularly Arabic and RTL interfaces.
• Experience integrating AI APIs with strict structured‑output requirements.
• Exposure to Azure services, including managed PostgreSQL, cloud storage, secrets management, monitoring, and application hosting.
• Experience with queues, notifications, file storage, webhooks, and production observability.
• Experience working in small, fast‑paced product teams with broad engineering ownership.

About the Product

You will contribute to an enterprise Talent Development Platform that helps organizations manage job architecture, competency frameworks, employee assessments, development plans, coaching, reassessment, and workforce intelligence.

The platform also supports integrations with enterprise HR systems and is built around a modern technology stack comprising React, TypeScript, Node.js, Drizzle ORM, and PostgreSQL, with PostgreSQL Row‑Level Security supporting tenant isolation.

The role requires a product engineering mindset, with a focus on building reliable, secure, scalable, and maintainable solutions for enterprise customers.

What We’re Looking For

We are looking for a hands‑on senior engineer who is comfortable working across frontend development, backend services, databases, security, testing, integrations, CI/CD, and production troubleshooting.

You should have experience taking meaningful ownership of a live multi‑tenant SaaS product and be comfortable using AI‑assisted development tools to improve productivity without compromising engineering quality.

Strong communication skills, a practical approach to problem-solving, and the ability to work independently in a fast‑moving environment are essential.