Senior Backend Engineer

virtuos holdings pte. ltd.; Singapore; Vor Ort; SGD 140.000 - 190.000; Vollzeit

Zusammenfassung

virtuos holdings pte. ltd. seeks a Senior Backend Engineer to design, develop, and maintain backend services and AI-powered applications. You will deliver new features, implement AI capabilities, and improve the reliability and performance of existing systems.

This hands-on role requires owning features from design through deployment, collaborating with cross-functional teams, and mentoring junior engineers as the organization scales its AI-driven products in a fast-paced environment.

Qualifikationen

• 5+ years of professional backend development experience, including 2+ years developing AI-powered applications or services
• Strong Python and FastAPI expertise, including asynchronous programming, type annotations, Pydantic, dependency injection, and RESTful API design
• Practical experience integrating AI APIs or SDKs, including prompt design, structured outputs, and streaming or asynchronous workflows
• Understanding of LLM challenges including context management, hallucinations, prompt injection, rate limits, and token costs
• Hands-on cloud experience (AWS/Azure/GCP)
• Solid PostgreSQL or relational DB skills with data modeling and query optimization
• Knowledge of secure API design, authentication/authorization, and secrets management
• Experience with testing (pytest), Git, CI/CD, and Docker
• Strong problem-solving and ability to navigate and improve existing codebase
• Strong written and verbal English and Chinese communication skills

Aufgaben

• Design, develop, and maintain scalable Python services and secure RESTful APIs using FastAPI
• Integrate AI capabilities and tools, including LLMs and AI SDKs, with well-defined input/output schemas
• Collaborate with cross-functional teams, review code, and mentor junior engineers
• Ensure reliability, performance, and maintainability of backend and AI integrations
• Write automated tests, improve logging, monitoring, and CI/CD pipelines
• Design multi-agent workflows when appropriate to meet business needs

Kenntnisse

Python

FastAPI

Async programming

RESTful APIs

English-Chinese

Pytest

Git & CI/CD

Docker

Problem solving

Cloud platforms

Tools

AWS

Azure

GCP

Vue

React

LangGraph

Claude Agent SDK

Pydantic AI

pgvector

vLLM

llama.cpp

Jobbeschreibung

About the Position

We are looking for a Senior BackendEngineer to design, develop, and maintain backend services and AI-poweredapplications. You will deliver new features, integrate AI capabilities, andimprove the reliability, performance, and maintainability of existing systems.

This is a senior, hands-on individualcontributor role. You will write code, contribute to architectural decisions,and collaborate with cross-functional teams to turn product requirements andemerging AI capabilities into production-ready solutions.

Responsibilities

Backend Development and Maintenance

• Build and maintain scalablePython services and secure RESTful APIs using FastAPI.
• Own features from technicaldesign and implementation through testing, deployment, and ongoing support.
• Extend existing applications,troubleshoot production issues, refactor code, and manage dependency upgradeswhile preserving API compatibility.
• Design and optimize databaseaccess, caching, and asynchronous processing.
• Implement authentication,authorization, input validation, and reliable error handling.

AI Application Development

• Integrate LLMs and other AIservices through provider APIs and SDKs, creating reusable interfaces forapplication teams.
• Design reliable APIs and toolinterfaces for AI applications, with well-defined input/output schemas,validation, and error handling.
• Develop AI workflows usingprompt orchestration, structured outputs, tool calling, and streamingresponses.
• Manage context limits, ratelimits, timeouts, retries, and provider failures to support reliable productionuse.
• Evaluate model and promptchanges against representative test cases, balancing output quality, latency,and cost.
• Design and develop multi-agentsystems and workflows, where appropriate, to address business requirements andautomate complex tasks.

Quality Delivery and Collaboration

• Write automated tests andmaintain regression coverage for backend services and AI integrations.
• Improve logging, metrics, andtracing to diagnose failures and monitor service performance and AI usage.
• Maintain CI/CD pipelines andcontainerized deployments in collaboration with infrastructure teams.
• Conduct code reviews, documenttechnical decisions, and mentor junior engineers.
• Partner with product, frontend,AI, and infrastructure teams to clarify requirements and deliver maintainablesolutions.

Must Have

• 5+ years of professional backend development experience, including2+ years developing AI-powered applications or services, with demonstrated ownership of service design, productiondeployment, and ongoing maintenance.
• Strong Python and FastAPI expertise,including asynchronous programming, type annotations, Pydantic, dependencyinjection, and RESTful API design.
• Practical experienceintegrating AI APIs or SDKs, including prompt design, structured outputs, andstreaming or asynchronous workflows.
• Understanding of common LLMchallenges, including context management, hallucinations, prompt injection,rate limits, and token costs.
• Hands-on public cloud experience, suchas AWS, Azure, or GCP, including deploying and operating backend applications.
• Solid database skills withPostgreSQL or another relational database, including data modeling and queryoptimization.
• Working knowledge of secure APIdesign, authentication and authorization, and secrets management.
• Experience designing reliablebackend services and external API integrations, including concurrency control,timeouts, retries, idempotency, and rate limiting, with the ability to explaindesign tradeoffs.
• Experience with pytest orequivalent testing tools, Git, CI/CD, and Docker.
• Strong problem-solving skillsand the ability to independently navigate, extend, and improve an existingcodebase.
• Strong written and verbal communication skills in both English andChinese, with the ability to explain technicaldecisions and tradeoffs across teams.

Nice to Have

• AWS experience, particularly with S3,SageMaker, DynamoDB, ECS, CloudWatch, or Secrets Manager.
• Frontend development experience with Vue or React, including TypeScript or JavaScript.
• Experience with agentframeworks such as LangGraph, Pydantic AI, Claude Agent SDK, or comparabletools, including multi-agent orchestration, task delegation, and contextsharing.
• Experience withretrieval-augmented generation (RAG), embeddings, and vector databases such aspgvector.
• Experience deploying local orself-hosted LLMs using tools such as vLLM, Ollama, or llama.cpp.
• Experience with multimodal AI,including image, audio, or 3D generation.