Java Developer

Job Description:

Summary

The Data Engineer will be responsible for designing, developing, and maintaining the data infrastructure. They must have experience with SQL and Python.

Roles & Responsibilities:

● Collaborate with product, business, and engineering stakeholders to understand key metrics, data needs, and reporting pain points.

● Design, build, and maintain clean, scalable, and reliable data models using DBT.

● Write performant SQL and Python code to transform raw data into structured marts and reporting layers.

● Create dashboards using Tableau or similar tools.

● Work closely with data platform engineers, architects, and analysts to ensure data pipelines are resilient, well-governed, and high quality.

● Define and maintain source-of-truth metrics and documentation in the analytics layer.

● Partner with product engineering teams to understand new features and ensure appropriate

instrumentation and event collection.

● Drive reporting outcomes by building dashboards or working with BI teams to ensure timely delivery of insights.

● Help scale our analytics engineering practice by contributing to internal tooling, frameworks, and best practices.

Who You Are:

Experience : 3 to 4 years of experience in analytics/data engineering, with strong hands-on expertise in DBT, SQL, Python and dashboarding tools.

● Experience working with modern data stacks (e.g., Snowflake, BigQuery, Redshift, Airflow).

● Strong data modeling skills (dimensional, star/snowflake schema, data vault, etc.).

● Excellent communication and stakeholder management skills.

● Ability to work independently and drive business outcomes through data.

● Exposure to product instrumentation and working with event-driven data is a plus.

● Prior experience in a fast-paced, product-led company is preferred.

Python Developer - AI/MLYour Responsibilities

• Develop, train, and optimize ML models using PyTorch, TensorFlow, and Keras.
• Build end-to-end LLM and RAG pipelines using LangChain and LangGraph.
• Work with LLM APIs (OpenAI, Anthropic Claude, Azure OpenAI) and implement prompt engineering strategies.
• Utilize Hugging Face Transformers for model fine-tuning and deployment.
• Integrate embedding models for semantic search and retrieval systems.
• Work with transformer-based architectures (BERT, GPT, LLaMA, Mistral) for production use cases.
• Implement LLM evaluation frameworks (RAGAS, LangSmith) and performance optimization.
• Design and maintain Python microservices using FastAPI with REST/GraphQL APIs.
• Implement real-time communication with FastAPI WebSockets.
• Implement pgvector for embedding storage and similarity search with efficient indexing strategies.
• Integrate vector databases (pgvector, Pinecone, Weaviate, FAISS, Milvus) for retrieval pipelines.
• Containerize AI services with Docker and deploy on Kubernetes (EKS/GKE/AKS).
• Configure AWS infrastructure (EC2, S3, RDS, SageMaker, Lambda, CloudWatch) for AI/ML workloads.
• Version ML experiments using MLflow, Weights & Biases, or Neptune.
• Deploy models using serving frameworks (TorchServe, BentoML, TensorFlow Serving).
• Implement model monitoring, drift detection, and automated retraining pipelines.
• Build CI/CD pipelines for automated testing and deployment with ≥80% test coverage (pytest).
• Follow security best practices for AI systems (prompt injection prevention, data privacy, API key management).
• Participate in code reviews, tech talks, and AI learning sessions.
• Follow Agile/Scrum methodologies and Git best practices.

Required Qualifications

• Bachelor's or Master's degree in Computer Science, AI/ML, or related field.
• 2–5 years of Python development experience (Python 3.9+) with strong AI/ML background.
• Hands-on experience with LangChain and LangGraph for building LLM-powered workflows and RAG systems.
• Deep learning experience with PyTorch or TensorFlow.
• Experience with Hugging Face Transformers and model fine-tuning.
• Proficiency with LLM APIs (OpenAI, Anthropic, Azure OpenAI) and prompt engineering.
• Strong experience with FastAPI frameworks.
• Proficiency in PostgreSQL with pgvector extension for embedding storage and similarity search.
• Experience with vector databases (pgvector, Pinecone, Weaviate, FAISS, or Milvus).
• Experience with model versioning tools (MLflow, Weights & Biases, or Neptune).
• Hands-on with Docker, Kubernetes basics, and AWS cloud services.
• Skilled in Git workflows, automated testing (pytest), and CI/CD practices.
• Understanding of security principles for AI systems.
• Excellent communication and analytical thinking.

Nice to Have

• Experience with multiple vector databases (Pinecone, Weaviate, FAISS, Milvus).
• Knowledge of advanced LLM fine-tuning (LoRA, QLoRA, PEFT) and RLHF.
• Experience with model serving frameworks and distributed training.
• Familiarity with workflow orchestration tools (Airflow, Prefect, Dagster).
• Knowledge of quantization and model compression techniques.
• Experience with infrastructure as code (Terraform, CloudFormation).
• Familiarity with data versioning tools (DVC) and AutoML.
• Experience with Streamlit or Gradio for ML demos.
• Background in statistics, optimization, or applied mathematics.
• Contributions to AI/ML or LangChain/LangGraph open-source projects.

JOB DESCRIPTION

Experience: 3-8 years

Location- Mumbai

Wissen Technology is now hiring for a Java Developer - Mumbai with hands-on experience in Core Java, algorithms, data structures, multithreading and SQL. We are solving complex technical problems in the 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 a highly motivated and expert team which has made a mark as a high-end technical consulting. 

Required Skills:

• Exp. - 3-8 years
• Experience in Core Java and Spring Boot.
• Extensive experience in developing enterprise-scale applications and systems. 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.
• Good knowledge of multi-threading and high-performance server-side development.
• Basic working knowledge of Unix/Linux.
• Excellent problem solving and coding skills.
• Strong interpersonal, communication and analytical skills.
• Should have the ability to express their design ideas and thoughts.

Required Experience

3 - 8 Years

Skills

Java/J2EE,

Spring,

microservices

+ 1 more

• Develop unit, integration, and functional tests within Grails/Java and contribute to new architectures design for multi-tier Java EE-based products in a SOA environment.
• Interact with Business Analysts to understand software build configuration and testing processes, documenting application functionality and programming accordingly.
• Collaborate with a talented software team to work on various types of applications, ensuring the building of backend APIs using Java-based technologies.
• Stay updated with the latest trends and technologies, conducting POCs on new technical stacks to support and maintain a portfolio of applications.
• Utilize core Java skills to define, design, develop, integrate, test, deploy, maintain, and troubleshoot applications and tools written in Java and other related languages.
• Provide technical expertise in Java development, including Spring, Hibernate, and building scalable solutions for large web application deployments.
• Participate in the full SDLC, from requirements and design to development, testing, and deployment, ensuring the implementation of best practices and industry-standard procedures.
• Possess hands-on experience with Java, J2EE, Spring Boot, microservices, and web services, while also demonstrating proficiency in writing enterprise-strength code and developing backend APIs.
• Work in an agile environment, supporting users by developing documentation and offering assistance with tools, while promoting established development standards and change control procedures.

Role: Java developer
Experience: 4+ years

Job description

○ Working experience on JAVA,Spring Boot. (on building web services?)

○ NOSQL DynamoDB knowledge is plus

○ Working experience in building micro services and distributed systems

○ Working experience on using messaging queues RabbitMQ/Kafka is plus