55 backend engineer jobs at 42 companies in Middletown, DE
1mo
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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
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
1mo
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Backend .NET Engineer
Philadelphia, Pennsylvania, United States
OnsiteFull Time
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
3w
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Backend Software Developer
Wayne, Pennsylvania, United States
HybridFull Time
Experience building backend services and APIs using Ruby/Rails, Python or NodeJS; familiarity with databases, integrations (SFTP/FTP, OAuth2, OIDC), security (TLS, SSH), Linux/Docker, testing and API tools.
Ruby, Ruby on Rails, Python, NodeJS, SFTP, FTP, OAuth2, OIDC, TLS, SSH, Postgresql, Mysql, MariaDB, rSpec, Postman, Linux, Docker, ReactJS, NewRelic, AWS, CI/CD
1mo
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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
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
2w
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Backend Software Engineer
Philadelphia, Pennsylvania, United States
HybridFull Time
Proficiency in Go, Python, Bash, and SQL; Linux and GCP experience; CI/CD and build tooling familiarity; experience in healthcare/regulated environments and building web services with OpenAPI.
Go, Python, Bash, SQL, JavaScript, Linux, GCP, Kubernetes, GKE, Cloud Firestore, Cloud Storage, BigQuery, GitHub Actions, Please, Bazel, Buck, Pants, OpenAPI, Windows, RDBMS
3w
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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
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
2w
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Drupal Backend Engineer, (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
$96k-$133k/yr RemoteFull Time
5+ YOE5+ years Drupal development with Drupal 11, ability to build custom modules/APIs, security and performance remediation, experience with DDEV/Docker, testing (Cypress, PHPUnit), Git workflows, and ability to obtain Public Trust clearance.
Drupal, DDEV, Docker, Xdebug, Cypress, PHPUnit, Git, GitHub Copilot, VS Code, PHPStorm, Jira, Confluence, Slack, Zoom, Microsoft Teams, Twig
1d
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Knowledge Engineer Manager - Back-end Engineer
Seattle or Milwaukee or Dallas or Columbus or Kirkland or Cincinnati or New York City or Cleveland or Oklahoma City or Austin or Albany or Chicago or St. Petersburg or Hartford or Pittsburgh or St. Louis or Miami or Sacramento or Raleigh or Minneapolis or Mountain View or Scottsdale or San Francisco or Morristown or Denver or Boston or Philadelphia or Des Moines or Overland Park or Los Angeles or Charlotte or Walnut Creek or Carmel or Houston or Arlington or Atlanta or Redmond or Bentonville or Beaverton or Nashville or Detroit or San Diego
$80k-$294k/yr HybridFull Time
5+ YOEMinimum 5 years in knowledge graph hydration, ontology mapping, graph and relational databases, vector databases, Python or Java, and REST API development; bachelor's degree or equivalent experience required.
RDF, OWL, SKOS, RDFS, SPARQL, R2RML, CSVW, SHACL, GraphDB, Stardog, Neo4j, Amazon Neptune, PostgreSQL, MySQL, SQL Server, Pinecone, Weaviate, Milvus, Qdrant, Elasticsearch, OpenSearch, Python, Java, SQL, JSON, XML, CSV, REST APIs, Apache NiFi, Airflow, Docker, Kubernetes, Helm, AWS Neptune, Azure Cosmos DB, GCP, Kafka, RabbitMQ, Git, GraphQL APIs, D3.js, Cytoscape.js, Terraform
2w
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Backend API Engineer Technical Lead II
Charlotte or Malvern
HybridFull Time
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
1mo
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Backend Software Engineers - King of Prussia, PA
King of Prussia, Pennsylvania, United States
$75k-$150k/yr OnsiteFull Time
2+ YOEU.S. citizen with valid passport and active Secret clearance; Bachelor's in STEM; 2+ years experience; familiarity with Rust/C/Java, Docker, gRPC, SDLC; exposure to containerization and Agile.
Rust, C, Java, Docker, gRPC, Kubernetes, Helm, Gitlab CI/CD, Python, Selenium, Cypress, Playwright
2w
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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
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
3w
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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
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
3w
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Lead Software Engineer
Wayne, Pennsylvania, United States
OnsiteFull Time
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
3w
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Lead Software Engineer (1308)
Wayne, Pennsylvania, United States
OnsiteFull Time
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
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Senior Software Engineer
Berwyn, Pennsylvania, United States
HybridFull Time
7+ YOE7+ years backend engineering with Java/Python, 2+ years hands-on AI/ML, experience designing distributed transactional systems in regulated fintech, security/observability knowledge, and production incident handling.
Java, Python, Spring Boot, SQL, Kafka, Kubernetes, Docker, LangGraph, RAG, Vector Stores
3w
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Senior Software Engineer
Baltimore, Maryland, United States
$140k-$160k/yr RemoteFull Time
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
3w
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Senior Software Engineer
Baltimore, Maryland, United States
$140k-$160k/yr RemoteFull Time
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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Senior AI Engineer
United States or Wilmington
$126k-$197k/yr RemoteFull Time
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
3w
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Senior Software Engineer
Baltimore or Austin or New York City or Washington or Maryland or Virginia
FieldFull Time
5+ YOE5+ years software engineering experience, B.Sc./M.Sc. in CS or related, experience with backend systems, cloud platforms, React/JavaScript frontend, APIs, SQL, and production deployments; strong communication and public-sector experience.
AWS, Azure, GCP, React, JavaScript, django, node, CI/CD, APIs, SQL
1w
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Staff Software Engineer
Philadelphia or United States
$169k-$192k/yr OnsiteFull Time
8+ YOE8+ years software engineering experience; proficiency in Python, Go, TypeScript or SQL; backend, APIs, distributed systems, Postgres, AWS/GCP, Docker/Kubernetes, Kafka/Redis; strong system design and cross-team leadership.
Python, Go, TypeScript, SQL, Postgres, AWS, GCP, Docker, Kubernetes, Kafka, Redis, Grafana, Prometheus, GitLab CI/CD
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