36 senior backend developer jobs at 27 companies in Elsmere, DE

PromotedHiringCafe
Founding Backend / Infra Engineer
Cupertino, CA, US
$160k-$300k/yr On-SiteFull Time
HiringCafe
HiringCafe: Building a 100× better job search engine to take on Indeed and LinkedIn.
Own the crawlers, pipelines, and infrastructure powering a real-time job search engine. Strong Node.js and Python fundamentals; bonus points for security and reverse-engineering chops.
Node.js, Python, Elasticsearch, Redis
2w
Save
Mark Applied
Hide
Senior Backend Engineer - Java
United States or Tampa or Boston or Atlanta or New York City or Columbus or Chicago or Philadelphia or Raleigh or Charlotte or Minneapolis or Dallas or Washington D.C. or Austin or Miami or Newark
$152k-$194k/yr RemoteFull Time
Real
RealNasdaq: REAX: Technology-driven brokerage offering residential real estate and title services.
8+ YOE8+ years experience with Java/Spring Boot, JPA/Hibernate, relational databases; experience designing event-driven microservices, strong testing practices, AI-assisted development familiarity, BA/BS or equivalent.
Java 17, Java 21, Spring Boot 3.x, JPA/Hibernate 6, Postgres, Kafka, DynamoDB, Redis, OpenSearch, AWS, Docker, Kubernetes, Datadog, ArgoCD, TeamCity, Claude Code, Cursor, Codex, Model Context Protocol (MCP), GitHub, SonarQube
1mo
Save
Mark Applied
Hide
Backend .NET Engineer
Philadelphia, Pennsylvania, United States
OnsiteFull Time
Comcast
ComcastNASDAQ: CMCSA: Provides global telecommunications, media content, and entertainment services.
5+ YOE5+ years backend development with C#/.NET, REST APIs, SQL/EF Core, CI/CD, automated testing, Git, cloud (Azure preferred), spec-first workflows (OpenSpec) and experience mentoring teammates.
C#, Microsoft .NET, ASP.NET Core, ASP.NET Core Web API, SQL, Entity Framework Core, Git, Azure, OpenSpec, GitHub Spec Kit, CI/CD
4w
Save
Mark Applied
Hide
Backend Engineer, Flag Delivery
Oakland or San Francisco or New York City or Boston or Seattle or Irvine or Los Angeles or Monterey or Santa Barbara or Santa Rosa or Austin or Portland or Philadelphia or Chicago or United States
$146k-$235k/yr OnsiteFull Time
LaunchDarkly
LaunchDarkly: Provides a feature management platform for software development teams.
5+ YOE5+ years backend engineering experience building/operating production distributed systems; strong programming in Go/Java/Rust; production debugging, observability, on-call experience; clear AI usage in engineering work.
Go, Java, Rust
5d
Save
Mark Applied
Hide
Sr. Backend Software Engineer (NodeJS)
United States or Minneapolis or Philadelphia or New Hartford or Austin or Champaign or Chicago
$140k-$160k/yr RemoteFull Time
PAR Technology
PAR TechnologyNYSE: PAR: Provides unified software and hardware for restaurant operations.
8+ YOEExpertise in Node.js/Typescript and PostgreSQL, 8+ years backend experience with distributed systems, GraphQL, TypeORM, Nest.js; familiarity with Kubernetes, message brokers, AWS, Terraform.
Typescript, NodeJS, Ruby, Rails, PostgreSQL, GraphQL, TypeORM, Nest.js, RabbitMQ, RMQ, React, AWS, Terraform, Helm, Kubernetes, EKS, Microsoft Teams
22h
Save
Mark Applied
Hide
Backend API Engineer Technical Lead II
Charlotte or Malvern
HybridFull Time
Vanguard
Vanguard: Provides mutual funds, ETFs, and investment management services.
8+ YOE8+ years related experience, 3+ years Node.js, proficient in TypeScript and NestJS, experience with AWS, CI/CD, GitHub Actions, REST/Spring Boot/Java a plus; undergraduate degree or equivalent; strong communication and mentoring skills.
Node.js, Typescript, NestJS, Visual Studio Code, RESTful Services, Spring Boot, Java, CI/CD Pipeline, Github Actions, Git/GitHub, JIRA, AWS ECS Fargate, AWS EKS, AWS Lambda, XCode, SWIFT, Android Studio
2mo
Save
Mark Applied
Hide
Senior Software Engineer, Backend
Philadelphia, Pennsylvania, United States
$160k-$210k/yr OnsiteFull Time
Perpay
Perpay: Financial platform offering interest-free shopping and credit building via payroll.
5+ YOE5+ years web apps; 2+ years leading teams; PostgreSQL; AWS; Docker/Kubernetes; Python/Django or Rails; strong communication.
JavaScript, Python, Django, Flask, React, React Native, Redux, Kubernetes, AWS, Docker, Celery, Redis, Datadog, CloudWatch
3d
Save
Mark Applied
Hide
Senior Software Engineer, Backend FinPlatform
New York City or San Francisco or Salt Lake City or Los Angeles or Seattle or Austin or Washington or Philadelphia or San Diego or Chicago or Atlanta or Australia or Canada or South America
$146k-$215k/yr RemoteFull Time
Flex
Flex: A financial platform allowing renters to split monthly rent payments.
6+ YOE6+ years software engineering experience, 4+ years with Java, experience with backend systems, APIs, data pipelines, AWS, and distributed teams.
Java, Spring, Gradle, JUnit, JVM, AWS, EKS, Aurora RDS, Elasticache, DynamoDB, GitHub Actions, git, DataDog, Snowflake, CDK, Terraform
7h
Save
Mark Applied
Hide
Senior Python Engineer, Integration
Philadelphia or New York City or Austin or Sofia or Europe
RemoteContract
Fliff
Fliff: Operates a social sportsbook platform offering free-to-play gaming.
5+ YOE5+ years Python development with API and system integrations, experience with observability and scalable backend architecture, willingness to join on-call rotations.
Python, Django, Datadog, CloudWatch, Grafana
2w
Save
Mark Applied
Hide
Senior AI Engineer
United States or Wilmington
$126k-$197k/yr RemoteFull Time
Chemours
ChemoursNYSE: CC: Manufactures specialty chemicals, refrigerants, and high-performance industrial fluoropolymers.
8+ YOEDegree in Computer Science/Engineering, 8+ years backend development with Python and JavaScript, 2+ years production GenAI systems experience, React/TypeScript UI skills, Pydantic proficiency, strong stakeholder communication.
Python, JavaScript, React.js, TypeScript, HTML, Pydantic, PyTorch, Azure, Azure Kubernetes, Office 365, GitHub
1mo
Save
Mark Applied
Hide
Nuuly Senior Software Engineer
Philadelphia, Pennsylvania, United States
OnsiteFull Time
Urban Outfitters
Urban OutfittersNASDAQ: URBN: Multi-brand retail operator of lifestyle apparel and home goods.
5+ YOE5+ years software engineering experience with ~2 years senior-level responsibilities; strong JVM (Java/Kotlin/Scala) or backend skills, microservices, cloud (GCP/AWS/Azure), Docker/Kubernetes, Postgres/AlloyDB, and practical LLM/AI tool use.
Java, Kotlin, Scala, Python, Go, Node, TypeScript, JVM, Spring, Google Cloud Platform (GCP), AWS, Azure, Docker, Kubernetes, Postgres, AlloyDB, Kafka, Spark, Storm, RESTful APIs, ChatGPT, Claude, Cursor, Windsurf, Copilot, MCP
2mo
Save
Mark Applied
Hide
Sr. Software Engineer
Wayne or Naperville
$120k-$135k/yr HybridFull Time
Frontline Education
Frontline EducationNYSE: ROP: Provides administrative and management software for K-12 school districts.
5+ YOE5–7 years backend engineering or intelligent systems with production impact; strong Python, CI/CD, and system design; experience with ML model APIs and cloud inference; familiarity with vector databases and retrieval systems.
Python, CI/CD, AWS Bedrock, Azure OpenAI, Google Vertex AI, PyTorch, Hugging Face Transformers, vLLM, FAISS, Pinecone, OpenSearch/KNN, LangChain, LlamaIndex, MLflow, Weights & Biases, Prometheus
1w
Save
Mark Applied
Hide
Senior Software Engineer – Mobile Development (iOS)
Philadelphia, Pennsylvania, United States
$105k-$110k/yr OnsiteFull Time
City of Philadelphia
City of Philadelphia: Provides municipal services and governance to the city of Philadelphia.
5+ YOE5+ years professional iOS development, strong Swift/Objective-C, Xcode, UIKit/SwiftUI/Combine, Core Data, App Store deployment, REST API integration, familiarity with backend tech and accessibility, bachelor\u0002s degree preferred, city residency within six months, cover letter required.
Swift, Objective-C, Xcode, UIKit, Core Data, SwiftUI, Combine, App Store Connect, Git, React Native, Node.js, SQL, PostgreSQL, Oracle, MSSQL, Amazon Web Services (AWS)
2w
Save
Mark Applied
Hide
Senior Software Engineer | Research Tech | Experienced Hire
Bala Cynwyd, Pennsylvania, United States
OnsiteFull Time
Susquehanna International Group
Susquehanna International Group: Global quantitative trading and market making firm.
5+ YOE5+ years software engineering experience; strong hands-on C#, Python, and React/JavaScript; full-stack backend/frontend comfort; excellent communication; Bachelor’s in CS, CE, math, physics or related.
C#, .NET, Python, React, JavaScript, Microsoft Excel
2mo
Save
Mark Applied
Hide
Sr. Software Engineer
Philadelphia or New Jersey or Delaware or New York or Maryland or Florida or South Carolina or Texas or Virginia or Georgia
HybridFull Time
FreedomPay: A fast-growing payments and commerce technology delivering secure solutions globally.
7+ YOE7+ years in application development and testing; strong web, SPA, and backend skills; security-focused; Agile experience; strong English communication.
.NET, SQL Server, MVC, jQuery, React, Angular, Redux, TypeScript, JWT, Git, HTML, CSS, Websockets
1w
Save
Mark Applied
Hide
Lead Software Engineer (1308)
Wayne, Pennsylvania, United States
OnsiteFull Time
autoMHatic Financial
autoMHatic Financial: Specialized lender for manufactured home loans with instant decisions.
5+ YOE5+ years backend/full-stack engineering experience with APIs, integrations, Snowflake, SQL, and modern DevOps; strong communication and ownership; experience mentoring offshore developers.
Snowflake, SQL, C#/.NET, Java, Node.js, Git, CI/CD, dbt, iPaaS
6d
Save
Mark Applied
Hide
Senior QA Engineer
Malvern, Pennsylvania, United States
OnsiteFull Time
Rajant
Rajant: Provides industrial wireless mesh networking for mission-critical connectivity.
5+ YOE5+ years QA experience for backend/platform/cloud/web applications; strong manual testing, test strategy, defect management; automation with Python/Pytest/Playwright/Selenium; API, Linux, Docker, SQL, Jira/Confluence experience.
Python, Pytest, Playwright, Selenium, Postman, Swagger/OpenAPI, Docker, Keycloak, Jira, Confluence, TestRail, Zephyr, Xray, PostgreSQL, Bash, Ansible
3mo
Save
Mark Applied
Hide
Vice President, Full Stack Engineer
Berwyn, Pennsylvania, United States
OnsiteFull Time
BNY
BNYNYSE: BK: Global institution managing and servicing financial assets worldwide.
5+ YOE5-9 years backend software development; Bachelor’s in CS/Engineering; finance experience; Java/Python/Node.js; Oracle DB; strong problem solving.
Java, Python, Node.js, Oracle Database
2mo
Save
Mark Applied
Hide
Software Engineer Staff
King of Prussia, Pennsylvania, United States
OnsiteFull Time
Lockheed Martin
Lockheed MartinNYSE: LMT: Designs and manufactures global security and aerospace systems.
Experience developing backend applications on Linux using C/C++ or Java; Agile (SAFe/Kanban/Scrum); design, test, debug complex applications; active TS/SCI clearance with poly required; initiative and domain interest in mission management/command and control.
C/C++, Java, Linux, SAFe, Kanban, Scrum, Ant, Git, Maven, Gradle, Jenkins, Jira, Confluence, Collaborator, Docker, Kubernetes, Matlab, STK, AWS
1mo
Save
Mark Applied
Hide
Senior Engineer - Product & Platform Engineering (Newark, Delaware, US)
Newark, Delaware, United States
OnsiteFull Time
Altimetrik
Altimetrik: Provides digital business enablement and platform engineering services for enterprises.
4+ YOE4+ years finance-domain Java backend experience with Spring Boot and microservices; B.Tech/M.Tech in CS or Software Engineering required; Docker/Kubernetes, MongoDB, Kafka, Git, JUnit experience preferred.
Java, J2EE, Spring, Spring Boot, ORM, InMemory cache/DB, MySQL, Oracle DB, REST, Microservices, JUnit, Docker, Kubernetes, MongoDB, Kafka, Git
1w
Save
Mark Applied
Hide
Lead Software Engineer
Wayne, Pennsylvania, United States
OnsiteFull Time
autoMHatic Financial
autoMHatic Financial: Provides consumer financing and loans for manufactured housing.
5+ YOE5+ years backend or full‑stack engineering experience focused on APIs, services, integrations, Snowflake, SQL, and modern DevOps/CI/CD practices.
Snowflake, SQL, C#/.NET, Java, Node.js, Git, CI/CD, dbt