Java Microservices

Wissen Technology is now hiring for Java Developer with hands on experience in Core Java, multithreading, algorithms, and data structure.

We are solving complex technical problems in the financial industry and need talented software engineers to join our mission and be a part of a global software development team.

A brilliant opportunity to become a part of highly motivated and expert team which has made a mark as a high-end technical consulting.

Required Skills:

Experience - 3+.

Experience in Core Java 5.0 and above, CXF, Spring.

Extensive experience in developing enterprise-scale n-tier applications for financial domain. Should possess good architectural knowledge and be aware of enterprise application design patterns.

Should have the ability to analyze, design, develop and test complex, low-latency client-facing applications.

Good development experience with RDBMS, preferably Sybase database.

Good knowledge of multi-threading and high-volume server-side development.

Experience in sales and trading platforms in investment banking/capital markets.

Basic working knowledge of Unix/Linux.

Excellent problem solving and coding skills in Java.

Strong interpersonal, communication and analytical skills.

Should have the ability to express their design ideas and thoughts.

Job Description

Key Responsibilities

• API & Service Development:
• Build RESTful and GraphQL APIs for e-commerce, order management, inventory, pricing, and promotions.
• Database Management:
• Design efficient schemas and optimize performance across SQL and NoSQL data stores.
• Integration Development:
• Implement and maintain integrations with ERP (SAP B1, ERPNext), CRM, logistics, and third-party systems.
• System Performance & Reliability:
• Write scalable, secure, and high-performance code to support real-time retail operations.
• Collaboration:
• Work closely with frontend, DevOps, and product teams to ship new features end-to-end.
• Testing & Deployment:
• Contribute to CI/CD pipelines, automated testing, and observability improvements.
• Continuous Improvement:
• Participate in architecture discussions and propose improvements to scalability and code quality.

Requirements

Required Skills & Experience

• 3–5 years of hands-on backend development experience in Node.js, Python, or Java.
• Strong understanding of microservices, REST APIs, and event-driven architectures.
• Experience with databases such as MySQL/PostgreSQL (SQL) and MongoDB/Redis (NoSQL).
• Hands-on experience with AWS / GCP and containerization (Docker, Kubernetes).
• Familiarity with Git, CI/CD, and code review workflows.
• Good understanding of API security, data protection, and authentication frameworks.
• Strong problem-solving skills and attention to detail.

Nice to Have

• Experience in e-commerce or omnichannel retail platforms.
• Exposure to ERP / OMS / WMS integrations.
• Familiarity with GraphQL, Serverless, or Kafka / RabbitMQ.
• Understanding of multi-brand or multi-country architecture challenges.

About the Role

We are looking for a Senior Backend Engineer to join our core engineering team and help build high-

throughput, low-latency services that power real-time trading at scale. What We’re Looking For

You are someone who has built backend systems in a regulated, high-stakes environment — ideally fintech, brokerage, payments, or banking. You think in terms of system reliability, data correctness, and operational

excellence. You take ownership of services end-to-end: from design and implementation through deployment, monitoring, and incident response. You communicate clearly, make pragmatic trade-offs, and hold yourself and

your peers to a high engineering bar. What You’ll Do

• Design, build, and own backend microservices for a real-time trading platform — from API contracts

through to production observability. • Work with databases, caches, and event-driven architectures to ensure high availability and data

consistency across distributed systems. • Build integrations with third-party financial services — clearing, settlement, identity verification, and

payment rails. • Define and enforce engineering standards — code reviews, testing strategies, API design conventions, and incident response processes. • Collaborate with product, design, and cross-functional teams to translate business requirements into

well-scoped technical deliverables. • Participate in on-call rotations and own production reliability for the services you build. • Mentor junior engineers and contribute to a culture of technical excellence and continuous improvement. Must-Have

• 5+ years backend engineering experience with Golang and Java in production. • Strong experience with PostgreSQL, Redis, and event-driven messaging (Kafka, NATS, or RabbitMQ). • Experience building and maintaining REST/gRPC APIs at scale with proper error handling, rate limiting, and versioning. • Understanding of financial systems — ledgers, reconciliation, order lifecycle, or payment processing.

• Experience with microservices architecture, API gateways, and service-to-service communication

patterns. • Familiarity with CI/CD pipelines, containerization (Docker/Kubernetes), and cloud infrastructure (AWS or

GCP). • Strong debugging and incident-response skills in distributed systems. Nice-to-Have

• Prior experience at a brokerage, wealth-tech, neo-bank, or payments company. • Experience with clearing broker integrations or introducing broker models. • Knowledge of compliance and regulatory requirements for cross-border financial products. • Experience with search infrastructure (Typesense, Elasticsearch). • Background in performance engineering — profiling, load testing, and latency optimization. Tech Stack

Languages Golang (primary), Java; Python (analytics/scripting)

Databases PostgreSQL, Redis, Typesense

Messaging Kafka, NATS, SSE / WebSocket

Infrastructure Docker, Kubernetes, AWS/GCP, Terraform

Integrations Clearing broker APIs, KYC providers, payment gateways

Observability Datadog / Grafana, PagerDuty, structured logging (ELK)

We're looking for highly skilled experienced engineers to design and build high-scale, cloud-based data processing systems that can handle massive amounts of data with low latency. You'll work with a team of smart, motivated, and diverse people and be given the autonomy and support to do your best work. This is a rare opportunity to make a meaningful impact in society while working in a dynamic and flexible workplace where you'll belong and be encouraged.

Qualifications:

• Bachelor's Degree required
• Significant experience with distributed systems.
• Experience with modern programming languages such as Java, C#, C/C++, or Ruby.
• Experience with container platforms such as DC/OS, Kubernetes
• Fluency in technologies and design concepts around Big Data processing and relational databases, such as the Hadoop ecosystem, Map/Reduce, stream processing, etc.
• Experience with production operations and good practices for putting quality code into production and troubleshooting issues when they arise.
• Effective communication of technical ideas verbally and in writing, including technical proposals, design specs, architecture diagrams, and presentations.
• Ability to collaborate effectively with the team and other stakeholders.
• Preferably, production experience with Cloud and data processing technologies.

Responsibilities:

As a member of the software engineering division, you will take an active role in the definition and evolution of standard practices and procedures. Define specifications for significant new projects and specify, design and develop software according to those specifications. You will perform professional software development tasks associated with the developing, designing and debugging of software applications or operating systems.

• Design and build distributed, scalable, and fault-tolerant software systems.
• Build cloud services on top of the modern OCI infrastructure.
• Participate in the entire software lifecycle, from design to development, to quality assurance, and to production.
• Invest in the best engineering and operational practices upfront to ensure our software quality bar is high.
• Optimize data processing pipelines for orders of magnitude higher throughput and faster latencies.
• Leverage a plethora of internal tooling at OCI to develop, build, deploy, and troubleshoot software.

Key Responsibilities:

• Rewrite existing APIs in NodeJS.
• Remodel the APIs into Micro services-based architecture.
• Implement a caching layer wherever possible.
• Optimize the API for high performance and scalability.
• Write unit tests for API Testing.
• Automate the code testing and deployment process.

Skills Required:

• At least 2.5 years of experience developing Backends using NodeJS — should be well versed with its asynchronous nature & event loop, and know its quirks and workarounds.
• Excellent hands-on experience using MySQL or any other SQL Database.
• Good knowledge of MongoDB or any other NoSQL Database.
• Good knowledge of Redis, its data types, and their use cases.
• Experience with graph-based databases like GraphQL and Neo4j.
• Experience developing and deploying REST APIs.
• Good knowledge of Unit Testing and available Test Frameworks.
• Good understanding of advanced JS libraries and frameworks.
• Experience with Web sockets, Service Workers, and Web Push Notifications.
• Familiar with NodeJS profiling tools.
• Proficient understanding of code versioning tools such as Git.
• Good knowledge of creating and maintaining DevOps infrastructure on cloud platforms.
• Should be a fast learner and a go-getter — without any fear of trying out new things Preferences.
• Experience building a large-scale social or location-based app.

5 years of architecture, design and programming experience preferably in fast-paced dynamic environment

Strong application design and implementation skills, solid understanding of the entire development cycle.

Strong background in Java/J2EE based application

Strong background in Spring/Spring boot based application

Strong background in Microservices based application

Experience working with Apache and/or Tomcat

Experience in transforming requirements to software design

Strong Experience with developing Java SAAS web applications.

Working experience in Industry Standard protocols related API Security including OAuth

Demonstrate strong design and programming skills using JSON, Web Services, XML, XSLT, PL/SQL in Unix and Windows environments.

Strong background working with Linux/UNIX environments.

Strong Shell scripting experience.

Working knowledge with Oracle, DB2 or MongoDB databases.

 Passion to stay on top of the latest happenings in the tech world and an attitude to discuss and bring those into play.  Strong agile/scrum development experience

 Strong collaboration and communication skills within distributed project teams

 Excellent written and verbal communication skills

Sr. Backend Developer | Disruptive HR Tech Platform | GGN

What you need to have:

Experience: 4 to 7 years