42 senior backend developer jobs at 32 companies in Townsend, 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
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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
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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
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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
3mo
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Senior Back-End Developer - United States
San Antonio or Baltimore or United States
RemoteFull Time
Maximus
MaximusNYSE: MMS: Provides government health and human services program administration.
10+ YOE5+ MgmtActive Top Secret/SCI clearance, bachelor’s degree in a related field, 10+ years experience, 5+ years back-end development with Python and PostgreSQL, experience with RESTful APIs, AWS, Kubernetes, RedHat Linux, CI/CD, DevSecOps, and related toolchains.
Python, PostgreSQL, Jira, AWS Infrastructure, Kubernetes, RedHat Linux, BASH, Spring, Ansible, JUnit5, Nexus Repository, Maven, RESTful API, DevSecOps, microservices, containers, CI/CD, Agile Test-Driven development
5d
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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
2mo
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Lead Backend Engineer (Node.js)
Baltimore, Maryland, United States
$120k-$170k/yr HybridFull Time
Alertus Technologies
Alertus Technologies: Provider of unified emergency mass notification and communication systems.
8+ YOELead Backend Engineer with 8+ years’ experience; strong Node.js skills; designing and scaling high-throughput, multi-tenant SaaS systems; proficient with relational and NoSQL databases and message brokers.
Node.js, PostgreSQL, MySQL, Redis, DynamoDB, MongoDB, RabbitMQ, Kafka, Terraform, Pulumi
22h
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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
3d
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Open Data Backend Engineer, (Senior Consultant, Engineering & Technical Services)
Baltimore or Alabama or California or Delaware or District of Columbia or Florida or Georgia or Maryland or New Jersey or New York or North Carolina or Pennsylvania or South Carolina or Tennessee or Texas or Virginia or West Virginia
$121k-$159k/yr RemoteFull Time
Fearless
Fearless: Digital services firm delivering IT solutions for government agencies.
7+ YOE7+ years engineering experience with Drupal 10–11, DKAN familiarity, PHP and SQL proficiency, Git/CI-CD, automated testing, Public Trust clearance eligibility, and US residency requirements.
Drupal 11, DKAN, CKAN, Socrata, DCAT, FHIR, SQL, Drush, Docker, DDEV, docker-compose, PHPUnit, Cypress, Xdebug, Git, Varnish, Akamai CDN, GraphQL, REST
2mo
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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
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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
4d
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Staff Software Engineer (Backend) - Billing Platform *HYBRID*
Palo Alto or Falls Church or Frisco or Washington or Baltimore or Dallas or Bethesda or Fort Worth
$110k-$230k/yr HybridFull Time
GEICO
GEICO: Provides vehicle and property insurance services to consumers.
8+ YOE8+ years software development experience with large-scale systems; proficiency in Java/Kotlin/Golang, SQL/NoSQL, Kafka, Spark, Airflow, cloud and DevOps practices; strong communication and system design skills.
Java, Kotlin, Golang, SQL, NoSQL, Kafka, Spark, Airflow
7h
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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
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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
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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
5d
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Senior Software Engineer
Baltimore, Maryland, United States
$140k-$160k/yr RemoteFull Time
Impruvon Health
Impruvon Health: Software and hardware for medication management in care settings.
5+ YOE5+ years software engineering experience; strong Ruby on Rails backend skills; product-minded; experience with React and Flutter, relational databases, security and reliability (HIPAA/SOC 2); strong communication.
Ruby on Rails, React, Flutter, AWS, ECS, RDS, S3
5d
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Senior Software Engineer
Baltimore, Maryland, United States
$140k-$160k/yr RemoteFull Time
Impruvon Health
Impruvon Health: Automated medication management and clinical workflow platform for providers.
5+ YOE5+ years software engineering experience, ownership of features from design to production, deep Ruby on Rails backend expertise, relational DB design, strong communication; React and Flutter experience preferred.
Ruby on Rails, React, Flutter, AWS, ECS, RDS, S3
1mo
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Software Engineer 2
Annapolis Junction, Maryland, United States
HybridFull Time
Entegra Systems
Entegra Systems: Provides engineering and intelligence analysis for government missions.
14+ YOESenior backend developer with TS/SCI CI Poly clearance; Java/Spring/Maven; 14+ years experience; BS in CS or related field; NoSQL/Big Data and CI tools
Java, Spring Framework, Maven, MongoDB, ElasticSearch, Jenkins, Git, PostgreSQL, Python, Hadoop, Hive, Pig, MapReduce, NoSQL
2mo
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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
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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
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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