142 sr api developer jobs at 71 companies in Hagerstown, MD
1mo
Save
Mark Applied
Hide
Application / API Lifecycle Automation Developer
Herndon, Virginia, United States
$160k-$195k/yr RemoteFull Time
5+ YOE5+ years designing and delivering API lifecycle automation, developer portals, CI/CD integrations, Zero Trust API security, and observability with documented automation metrics.
AppDynamics, ELK, OpenTelemetry, Backstage, Stoplight, Kong Dev Portal, Apigee Developer Portal, Kong, Apigee, MuleSoft, Azure API Management (Azure APIM), AWS API Gateway, CI/CD
2mo
Save
Mark Applied
Hide
Senior API Systems Engineer
Sterling, Virginia, United States
$150k-$254k/yr OnsiteFull Time
10+ YOEU.S. person with Top Secret/SCI polygraph clearance, 10+ years' relevant experience, Bachelor’s or Master’s in a STEM field, Security+ CE (DoDD 8140), 5+ years API gateway experience, proficiency with Java/Python/C#, cloud (AWS/Azure/GCP), Docker/Kubernetes.
Java, Python, C#, AWS, Azure, Google Cloud Platform, Docker, Kubernetes, Istio, Linkerd, MuleSoft, Apigee, Broadcom API, ServiceNow, Windows, Linux
2mo
Save
Mark Applied
Hide
Sr. AI Integration Engineer
Des Moines or Ashburn or Austin or Chaska or Chicago or Dallas or Lewisville or Kansas City or Nashville or Florida or Georgia or North Carolina or New Jersey or Pennsylvania
HybridFull Time
5+ YOE5+ years in software engineering, systems integration, and AI-enabled workflow delivery; experience with enterprise integrations (ServiceNow, Salesforce), cloud deployments, Python, APIs, and middleware.
Python, JavaScript, TypeScript, Java, C#, APIs, ServiceNow, Salesforce, Kubernetes, Docker, AWS, Azure, GCP, SQL, LangChain, LlamaIndex, Semantic Kernel
1mo
Save
Mark Applied
Hide
Sr. Software Engineer
Herndon, Virginia, United States
OnsiteFull Time
Active TS/SCI with polygraph required; strong full‑stack skills with Angular, Spring Boot, Java; experience with APIs, DevOps/CI-CD, microservices, AWS, Python, Kubernetes; bachelor\u0002s degree in CS or related field.
Angular, Spring Boot, Java, GitHub, Jenkins, JIRA, AWS, AWS Lambda, Python, Kubernetes
2w
Save
Mark Applied
Hide
Sr. Systems Engineer III (6706)
Reston or Herndon or Tysons Corner
$166k-$202k/yr HybridFull Time
10+ YOEActive TS/SCI with CI Polygraph, 10+ years technical leadership, advanced degree preferred, hands-on AI/ML and data pipelines, cloud (AWS/Azure), containerization, security and enterprise integration experience.
AWS, Azure, MLOps, DoDAF, SAFe Agile, IV&V, API
1mo
Save
Mark Applied
Hide
SME Systems Engineer- API Gateway & Cloud Architecture
Sterling, Virginia, United States
$180k-$230k/yr OnsiteFull Time
16+ YOEBachelor's in STEM, 16+ years' experience, DoD 8140/Security+ CE, 5+ years API Gateway experience (Broadcom preferred), expertise with Windows and cloud-hosted COTS, Java/Python/C#, AWS/Azure/GCP, Docker, Kubernetes, Agile, cloud architecture, troubleshooting, and system testing. TS/SCI w/ Poly required; U.S. citizenship required.
API Gateway, Broadcom API Gateway, MuleSoft, Apigee, Istio, Linkerd, ServiceNow, Docker, Kubernetes, Java, Python, C#, Windows, AWS, Microsoft Azure, Google Cloud, Message queues, Streaming platforms, ETL, COTS, MBSE
3w
Save
Mark Applied
Hide
Sr. Software Engineer (TS/SCI)
Hampton or Annapolis Junction or Alexandria or Chantilly or Washington or Reston or McLean or Herndon or Bethesda or Catonsville or Frederick or Ashburn
$144k-$268k/yr HybridFull Time
4+ YOEU.S. citizen with TS/SCI clearance (or immediate DISS eligibility), Bachelor’s degree, 4+ years Python or Java, hybrid cloud/app development, databases, ETL, algorithm design, CI/CD and stakeholder interfacing.
Python, Java, MongoDB, Celery, Azure DevOps, Jenkins, React.js, Node.js, Web API, IBM CPLEX, Gurobi, SPSS, SAS, R, PyCharm, VS Code, Jupyter Notebooks, Pandas, NumPy, Dask, Matplotlib, Seaborn, Plotly, Git, GitHub, GitLab, Docker, Podman
1w
Save
Mark Applied
Hide
AI Automation Engineer / Developer
Frederick, Maryland, United States
OnsiteFull Time
Strong software development skills (e.g., Python, JavaScript/TypeScript), hands-on experience with AI tools (Claude) and automation, API integration experience, discretion with confidential client data, and ability to deliver production systems.
Claude, Python, JavaScript, TypeScript, APIs
1mo
Save
Mark Applied
Hide
Sr. Front-End Software Engineer (Geospatial & Middleware)
Sterling, Virginia, United States
OnsiteFull Time
8+ YOEActive Top Secret clearance, Bachelor’s in CS or related,8+ years front-end experience, strong JavaScript and modern frameworks, Protobuf and middleware experience, experience with Kafka/RabbitMQ/ActiveMQ/ZeroMQ, API development, geospatial UI experience.
JavaScript, React, Angular, Vue, Protobuf, Apache Kafka, RabbitMQ, ActiveMQ, ZeroMQ, gRPC, FlatBuffers, Avro, GitLab, AMQP, MQTT, Data Distribution Services, Cesium JS, Open Layers, Leaflet, Mapbox, WebGL
1mo
Save
Mark Applied
Hide
GenAI Developer
Ashburn, Virginia, United States
HybridFull Time
7+ YOEU.S. citizen able to pass CBP background check; BA/BS preferred (experience considered); 7+ years full-stack development; React/Angular, SQL/NoSQL, Python/Java/JavaScript/TypeScript; GenAI concepts and APIs; AWS and Google cloud experience; DevSecOps knowledge.
React, Angular, SQL, NoSQL, Large Language Models (LLMs), transformers, Python, Java, JavaScript, TypeScript, AWS, Google Vertex AI, AWS Bedrock, GitLab, APIs, RESTful services, DevSecOps, CDNs
4d
Save
Mark Applied
Hide
Principal Systems Engineer (API Gateway) - TS/SCI w CI Poly
Sterling, Virginia, United States
OnsiteFull Time
16+ YOEBachelor's degree and 16+ years designing enterprise systems, cloud architectures, and API solutions, including 5+ years with API gateways. Requires active TS/SCI with CI Polygraph and Security+ CE.
REST, GraphQL, AWS, Microsoft Azure, Java, Python, C#, Broadcom API Gateway, MuleSoft, Apigee, Istio, Linkerd, Google Cloud Platform (GCP), Oracle Cloud Infrastructure (OCI), IBM Cloud, ServiceNow, Windows
3mo
Save
Mark Applied
Hide
Software Developer
Herndon or Chantilly
$185k-$240k/yr OnsiteFull Time
6+ YOEActive TS/SCI with Full-Scope Polygraph, 6+ years software development, experience with Java/Python/C++/JavaScript, APIs, Git, Agile; cloud, DevOps, containerization preferred.
Java, Python, C++, JavaScript, AWS, Azure, Docker, Kubernetes, Git, REST APIs, CI/CD Tools, DevOps
1mo
Save
Mark Applied
Hide
SME Systems Engineer - API (TS/SCI w/ CI Poly required)
Sterling, Virginia, United States
OnsiteFull Time
10+ YOEActive TS/SCI with CI poly, Security+ CE or higher, 10+ years relevant experience, STEM degree, API gateway expertise (5+ years), Java/Python/C# proficiency, cloud and containerization experience.
API gateway, Broadcom API, AWS, Azure, Google Cloud Platform, Docker, Kubernetes, Java, Python, C#, MuleSoft, Apigee, Istio, Linkerd, ServiceNow
1mo
Save
Mark Applied
Hide
Agile Developer
Herndon or United States
RemoteFull Time
5+ YOEBachelor's degree in CS/IT/Engineering, 5+ years software development in Agile, experience with Java/C#/JavaScript/Python, web services/APIs, Git, CI/CD and DevSecOps, and knowledge of secure coding and federal cybersecurity.
Java, C#, JavaScript, Python, VistA, MUMPS, CPRS, AWS, Azure, Google Cloud, Docker, Kubernetes, React, Angular, Vue.js, HL7, FHIR, Git, CI/CD, DevSecOps
2w
Save
Mark Applied
Hide
Software Developer, Senior
Herndon, Virginia, United States
$87k-$198k/yr OnsiteFull Time
6+ YOE6+ years software development; 3+ years with legacy enterprise systems; experience with microservices, APIs, Git; HS diploma/GED; TS/SCI clearance with polygraph required.
Python, Java, JavaScript, React, Angular, NodeJS, Git, AWS, Azure, Google Cloud Platform
3w
Save
Mark Applied
Hide
Senior Application Developer
Denver or Springfield or Sterling or St. Louis
$75k-$158k/yr OnsiteFull Time
8+ YOEBachelor's in CS or related,8+ years software development experience,expert Java and/or Python,REST APIs,databases,CI/CD,GIT,TS/SCI clearance and polygraph willingness.
Java, Python, ArcGIS, GeoServer, OpenLayers, Cesium, Kubernetes, AWS/C2S, Git, CI/CD
1mo
Save
Mark Applied
Hide
GenAI Developer
Ashburn, Virginia, United States
$52-$94/hr OnsiteFull Time
7+ YOEU.S. citizenship and CBP background check, BA/BS or equivalent experience, 7+ years full-stack development (React/Angular, SQL/NoSQL), familiarity with LLMs and GenAI, Python/Java/JavaScript/TypeScript, cloud (AWS, Google), API and DevSecOps experience.
React, Angular, SQL, NoSQL, Python, Java, JavaScript, TypeScript, AWS, Google, Google Vertex AI, AWS Bedrock, GitLab, RESTful services, DevSecOps
1mo
Save
Mark Applied
Hide
IT Software Application Developer II (79635)
Sterling, Virginia, United States
OnsiteFull Time
10+ YOEBachelor's in CS or related (or equiv. experience); 10+ years full-stack web development with Java and .NET; experience with Spring Boot, ASP.NET MVC/Web API, Azure, Angular, HL7/FHIR, SQL databases, CI/CD, and healthcare compliance (HIPAA).
Java, .NET, ASP.NET MVC, Web API, Spring Boot, Azure, Angular, FHIR, HL7, EHR, SQL Server, PostgreSQL, SVN, Git, CI/CD, Jenkins, GitHub, Azure DevOps, Power BI, Pentaho, Microservices
1mo
Save
Mark Applied
Hide
React Developer Senior
Ashburn, Virginia, United States
$120k-$160k/yr HybridFull Time
5+ YOE5+ years React and UI development experience, BS in CS/Engineering, TypeScript/JavaScript, HTML4/5, CSS/SCSS, Jest/Enzyme/React Testing Library, experience with complex backend APIs, strong communication and critical thinking.
React, Microsoft Visual Studio Code, TypeScript, JavaScript, MVC, MVVM, JSON, HTML4/5, CSS, SCSS, Jest, Enzyme, React Testing Library, Chrome DevTools
6d
Save
Mark Applied
Hide
Senior Developer
Herndon, Virginia, United States
OnsiteFull Time
10+ YOEActive US security clearance (TS/SCI with CI polygraph), 10+ years experience (or 15+ with BS), proficiency in Java/Python/C#, RESTful APIs, containerization, databases, Agile/DevSecOps.
Java, Python, C#, RESTful APIs, RDF, OWL, SPARQL, Docker, Kubernetes, OpenShift, CI/CD, Git