MERN Stack Developer (Permanent WFH)

Job Title : Senior Java Developer

Experience : 6+ Years

Shift Timing : 01:00 PM to 10:00 PM

Domain : Clinical Research

Location : Noida, Gurgaon & Pune

Mandatory Skills :

Java 8+, Hibernate, Oracle, PostgreSQL, JAX-RS (RestEasy), Jackson, REST APIs, JSP, React.js, GitHub, GitHub Actions, SonarQube, SonarLint, and AWS (IAM, SNS, SQS, S3, CloudWatch).

Job Summary :

We are looking for an experienced Senior Java Developer with 6+ years of experience to join the software development team of a leading Clinical Research organization.

The role involves developing and enhancing enterprise applications, building scalable APIs, and contributing to feature development while ensuring code quality and best practices.

Key Responsibilities :

• Develop and maintain enterprise applications using Java 8+ and Hibernate.
• Design and consume RESTful APIs using JAX-RS (RestEasy) and Jackson.
• Work with Oracle and PostgreSQL databases, including complex query writing.
• Develop UI components using JSP and React.js.
• Utilize GitHub and GitHub Actions for version control and CI/CD processes.
• Ensure code quality through SonarQube and SonarLint.
• Work with AWS services including IAM, SNS, SQS, S3, and CloudWatch.
• Collaborate with cross-functional teams to deliver high-quality solutions.

Note : Candidates should preferably be sourced from organizations within the Grid ecosystem.

About ZYSYGY

ZYSYGY is building Germany's zero-fee payment network. Merchants pay zero transaction fees. We route payments directly over SEPA Instant, bypassing Visa, Mastercard, and the entire card network chain. No hardware. No card reader. Just a phone.

We are building the first company to combine a fully software-based merchant POS with a consumer super-app for everyday financial life: payments, transport, utilities, government services, all in one place. Think what UPI did for India. We are doing it for Germany, from the ground up, on banking rails.

Role Overview

You will join the core engineering team as a founding engineer. You will own the backend payment engine end to end: transaction flows, wallet management, SEPA Instant settlement, KYB/KYC integration, recurring mandates, refund logic, and the compliance export layer (DATEV, Kassenbuch, GoBD, fiskaltrust). On mobile, you will contribute to the React Native consumer and merchant apps alongside our mobile engineer.

You will own what you build from development through deployment, monitoring, and production reliability. The architecture decisions you make in the first six months will run in production for years.

What you will do

Design and build the backend payment engine: transaction flows, wallet management, SEPA Instant settlement, offline payment authorization, and recurring mandate billing.

Own KYB/KYC integration and the compliance export layer: DATEV, Kassenbuch, GoBD, and fiskaltrust for KassenSichV.

Build REST APIs for financial-grade reliability and high-throughput transaction processing, including full R-transaction handling and reconciliation pipelines.

Contribute to the React Native consumer and merchant mobile apps alongside our mobile engineer.

Own the full lifecycle of what you build, from development through deployment, monitoring, and continuous improvement.

Integrate AI tooling into your development workflow as a matter of course: code generation, automated testing, and intelligent review.

Who you are

Meaningful hands-on experience building payment systems, fintech infrastructure, or financial APIs.

You have designed a ledger. You understand double-entry bookkeeping, immutable transaction records, and why you never update a financial row.

You have solved the partial failure. Money left one wallet and did not arrive in the other. You know how to detect it, resolve it, and make sure it does not happen again.

You understand idempotency at a design level. You have built systems that survive client retries, duplicate webhooks, and network drops without double-charging anyone.

You have built or reasoned about reconciliation: detecting discrepancies between your internal ledger and an external settlement file, and resolving them reliably at scale.

You understand KYC and KYB state machines, what happens when verification status changes mid-transaction, and what a regulator expects from your audit trail.

You are comfortable with SQL databases and own the full lifecycle of your code from development through deployment.

You can communicate technical decisions clearly to non-technical stakeholders. At this stage of the company, that matters.

You are a continuous learner. Payments infrastructure is a deep domain and you treat it that way.

You are comfortable with ambiguity and early-stage risk. There is no playbook yet. You will help write it.

Strong academic background preferred. Demonstrated engineering ability matters more than institution.

Relocation

Relocation to Munich, Germany, is on the table for the right candidate, including visa support.

Connect with the Founder

You can also connect with me on LinkedIn at www.linkedin.com/in/shabbir-maimoon

Position: Microsoft .NET Full Stack Developer

Experience: 4–6 Years

Open Positions: 10

Location: PAN India (Final Round – Face-to-Face Interview)

Budget: Up to 15 LPA

Notice Period: Immediate joiners preferred

Key Responsibilities:

· Work on highly distributed and scalable system architecture

· Design, develop, test, and maintain high-quality software solutions

· Ensure performance, security, and maintainability of applications

· Collaborate with cross-functional teams and stakeholders

· Perform system testing and resolve technical issues

Required Skills:

· Strong experience in ASP.NET, C#, .NET Core, MVC

· Hands-on experience with SQL Server / PostgreSQL

· Experience in Angular / React (Frontend technologies)

· Knowledge of microservices architecture & RESTful APIs

· Familiarity with CQRS pattern

· Exposure to AWS / Docker / Kubernetes

· Experience with CI/CD pipelines (Azure DevOps, Jenkins)

· Knowledge of Node.js is an added advantage

· Understanding of Agile methodology

· Good exposure to cybersecurity and compliance

Technology Stack:

· Microsoft .NET technologies (primary)

· Cloud platforms: AWS (SaaS/PaaS/IaaS)

· Databases: MSSQL, MongoDB, PostgreSQL

· Caching: Redis, Memcached

· Messaging queues: RabbitMQ, Kafka, SQS

• Minimum of 3 years of hands-on experience in React.js development. Proficient in JavaScript, ES6/ES7, HTML5, and CSS3.
• Strong understanding of React.js and its core principles. Experience with state management libraries, particularly Redux.
• Knowledge of modern frontend build tools and package managers (e.g., Webpack, npm).
• Solid understanding of RESTful APIs and asynchronous request handling.
• Familiarity with code versioning tools, such as Git. Strong problem-solving skills and attention to detail.
• Excellent communication and collaboration skills.
• Experience with TypeScript. Familiarity with GraphQL.
• Knowledge of front-end testing frameworks (e.g., Jest, Enzyme).
• Previous contributions to open-source projects or an active GitHub profile.
• Understanding of CI/CD pipelines.

You will be responsible for developing features on the application and integrations end to end. You will be working closely with the Technical Team to come up with high-quality, resilient, and highly performant applications.

• Design and develop SaaS-based applications based on microservices architecture.
• Work on the core backend and ensure it meets the performance benchmarks.
• API and Integrations.
• Designing and developing APIs for the front end to consume.
• Constantly improve the architecture of the application by clearing the technical backlog.
• Meeting both technical and consumer needs.
• Staying abreast of developments in web applications and programming languages.
• Work on the front end with ReactJS is a plus point.

• An enthusiastic individual with the following skills. We are open to promising candidates who are passionate about their work and are team players.
• A subset of the below skills should be fine as long as you are good.
• OAuth, API Integrations.
• Overall 6+ yrs of experience.
• Agnostic/Polyglot with multiple tech stacks.
• Worked on open source technologies – NodeJS, ReactJS, MySQL, NoSQL, MongoDB, CouchDB, DynamoDB, Clickhouse, Kafka.
• Backend exposure – good knowledge of building and integrating APIs.
• Efficient in building microservices in combining server & front-end.
• Knowledge of cloud architecture.
• Excellent knowledge and understanding skills on OAuth.
• Should have sound working experience with relational and columnar DB.
• Should be innovative and communicative in approach.
• Will be responsible for functional/technical track of a project.

You will closely work with the engineering team and support the Product Team of Plum.

A fast-growing SaaS commerce company based in Bangalore with offices in Delhi, Mumbai, SF, Dubai, Singapore, and Dublin. We have three products in our portfolio: Plum, Empuls and Compass. Xoxoday works with over 1000 global clients. We help our clients in engaging and motivating their employees, sales teams, channel partners or consumers for better business results.

We look forward to connecting with you. As you may take time to review this opportunity, we will wait for a reasonable time of around 3-5 days before we screen the collected applications and start lining up job discussions with the hiring manager. We however assure you that we will attempt to maintain a reasonable time window for successfully closing this requirement. The candidates will be kept informed and updated on the feedback and application status.