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Senior Python Developer Jobs in Leesburg, VA, US
2,200+ senior python developer jobs from 510+ companies hiring in Leesburg, VA, US.
8h
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Software Engineer Subject Matter Expert (SME)
Chantilly, Virginia, United States
OnsiteFull Time
5+ YOESenior Software Engineer with 5+ years in software development; proficient in Python, Java/.NET, Angular, and data processing; TS/SCI clearance; Agile/SAFe.
Python, Angular, Java, DotNet, SQL, REST API, Git, Apache NiFi, Terraform, GraphQL, React, SAFe
5d
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Senior Principal Software Engineer
New York City or Boston or Atlanta or Arlington or Miami or O'Fallon or San Francisco
$212k-$407k/yr HybridFull Time
Senior technical leadership; cloud-native platforms; distributed systems; real-time AI/ML inference; API design; data pipelines; MLOps; strong communication.
Java, Go, Python, AWS, Azure, GCP, Distributed Systems, Microservices, APIs, Data Pipelines, MLOps, Real-time Inference
6d
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Senior Data Analytics Engineer
Reston, Virginia, United States
OnsiteFull Time
5+ YOE5+ years in data and analytics; strong SQL, dimensional modeling; Python, PySpark; experience with Microsoft Fabric and Medallion architecture; ML/AI experience; Git; data governance.
SQL, Python, PySpark, SparkSQL, Microsoft Fabric, Foundry, Git, Power BI
1w
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Senior Systems Engineer - TS/SCI
Bethesda, Maryland, United States
HybridFull Time
12+ YOEActive Top Secret/SCI clearance, BS in Engineering/CS/Systems Engineering with 12+ years experience; MBSE; Agile; Scrum Master; Gitlab/JIRA/Confluence; strong communication; Python/Java/React a plus.
Gitlab, JIRA, Confluence, MBSE, Python, Java, React, Jenkins, Bamboo
3w
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FLEX Senior Software Engineer – Data and Analytics Technology
Bethesda, Maryland, United States
$48-$87/hr HybridFull Time
8+ YOE8+ years in data/ETL, 4+ years in data pipelines on AWS/Snowflake, leadership experience; strong communication; BS in Computer Science or related field.
AWS, Snowflake, S3, Lambda, EKS, Airflow, Python, Informatica, Spark, HashiCorp
1mo
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Senior Data AI Engineer
Alexandria, Virginia, United States
RemoteFull Time
7+ YOESenior data/AI engineer with 7+ years in data engineering or AI, strong Python, data validation, and experience with LLMs and DoD programs.
Python, FastAPI, MongoDB, Amazon S3, Redis, OpenAI API
6d
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GXM Technologies LLC - Senior Full Stack Application Developer (.NET MAUI)
Arlington, Virginia, United States
OnsiteFull Time
6+ YOE6+ years in .NET/C#, cross‑platform mobile development; US citizen; ability to obtain government clearance; BS/MS in CS/Engineering; 3+ years with SQL databases; Agile experience.
C#, .NET MAUI, Xamarin Forms, SQL Server, SQL, PowerShell, Python
1mo
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Senior Solutions Engineer, Federal
Washington, District of Columbia, United States
$160k-$200k/yr RemoteFull Time
5+ YOE5+ years engineering or deployment experience; strong software background; active Top Secret/SCI clearance or equivalent; able to scope and deliver complex gov deployments; comfortable travel up to 50%; proficient in Python/JavaScript.
Python, JavaScript, Rust, Terraform, Kubernetes, AWS GovCloud, Azure Government
1mo
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Software Developer
Winchester, Virginia, United States
OnsiteFull Time
5+ YOE5+ years software development; Top Secret/SCI-friendly clearance; proficient in C#, Java, or Python; experience with microservices, Docker, Kubernetes; use of TDD/BDD in Agile.
Docker, Kubernetes, C#, Java, Python, TDD, BDD, Agile
1w
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Systems Engineer Senior Level
Laurel, Maryland, United States
$160k-$215k/yr OnsiteFull Time
Senior Systems Engineer with TS/SCI clearance and polygraph; experience with DNS/DHCP/IPAM (DDI), Infoblox, network automation; scripting (Python/Perl); RMF; strong problem-solving.
Infoblox, DNS, DHCP, IPAM, Load Balancing, F5, Python, Perl, RMF
3w
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Software Engineer, Level 3
Annapolis Junction, Maryland, United States
OnsiteFull Time
12+ YOESenior software engineer with 12+ years of software development experience; strong Java/Python/C/C++ skills; Spring Boot; distributed systems; Docker/Kubernetes; CI/CD; TS SCI with poly required.
Java, Python, C, C++, Spring Boot, Kafka, JMS, Oracle, Elasticsearch, Docker, Kubernetes, Maven, Gradle, GitLab, Angular
1mo
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Software Developer 3 (SWD3)
Annapolis Junction, Maryland, United States
OnsiteFull Time
15+ YOESenior software developer with Java, Linux/UNIX, and full lifecycle software development; experience with AWS, Spring, and middleware; DoD 8570 IAT Level II certification.
Java, AWS, Angular, Hibernate, PostgreSQL, Docker, Podman, JHipster, XML/XSD, C++, Python, Perl, Ruby on Rails, Django, Spring Framework, Eclipse, JBuilder
1w
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Senior Systems Integration Engineer
Reston, Virginia, United States
$136k-$184k/yr OnsiteFull Time
8+ YOETS/SCI with CI Poly; 8+ years experience; US citizenship; Bachelor's degree; Linux CLI; Python; NiFi; Grafana; REST APIs; SQL databases; security certifications (8570/IAT Level 2); on-site in Reston, VA.
Apache NiFi, Python, Grafana, Microsoft Visio, SQL databases (Oracle, MySQL, PostgreSQL), Linux, RESTful APIs, Active Directory
2mo
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Senior Engineer, Spectrum Management & Development, Americas (McLean, VA, US)
McLean, Virginia, United States
OnsiteFull Time
5+ YOELead spectrum management, development, and regulatory coordination; 5+ years engineering experience; English fluency; travel ~30%.
Python, MATLAB, SQL
1mo
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Software Engineer Level 4
Annapolis Junction, Maryland, United States
OnsiteFull Time
Backend developer with data engineering and API development; Python, FastAPI, PostgreSQL, Elasticsearch; TS/SCI with CI Poly.
Python, FastAPI, PostgreSQL, Elasticsearch
2w
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Senior Appian QA Automation Engineer
McLean, Virginia, United States
$137k-$165k/yr RemoteFull Time
5+ YOE5+ years QA automation; Appian or low-code testing experience; Python automation; CI/CD with GitLab/Jenkins/Azure DevOps; API and performance testing; multi-project QA leadership; able to obtain Secret clearance; remote with East Coast hours.
Python, GitLab, Jenkins, Azure DevOps, Locust, JMeter, Selenium, Playwright, Appian
2mo
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Sr. AI Developer, GS (Chantilly, VA, US, 20151)
Chantilly, Virginia, United States
$116k-$189k/yr OnsiteFull Time
5+ YOE5+ years Python ML, DL, LLMs; strong MLOps; cloud platforms; gov't compliance; security-focused AI.
Python, TensorFlow, PyTorch, Scikit-learn, Hugging Face, LangChain, OpenAI, AWS SageMaker, Azure ML, Google Vertex AI, MLflow, Airflow, Kubeflow, FAISS, Pinecone, Retrieval-Augmented Generation, CMMC, FedRAMP, NIST
2w
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Senior Network Engineer
Seattle or Reston or New York or San Jose
$162k-$242k/yr HybridFull Time
10+ YOE10+ years in network engineering; experience with FedRAMP Moderate/High; multi-region/global routing; automation; strong communication.
BGP, OSPF, JunOS, EOS, NX-OS, IOS-XE, Python, Ansible/AWX, Git
1w
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Senior Security Engineer
Columbia, Maryland, United States
$138k-$184k/yr HybridFull Time
5+ YOE5+ years in a customer-facing technical sales/engineering role with PoV engagements; strong cloud and network security knowledge; vulnerability management; excellent communication.
Nessus, Python, REST/GraphQL, Terraform, AWS, Azure, Google Cloud, Docker, Kubernetes, IAM, AI security concepts
2w
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Senior Data Engineer
Washington or Richmond or United States
$86k-$110k/yr RemoteFull Time
4+ YOE4+ years in data architecture/analytics consulting; strong SQL and data modeling; experience with data pipelines and warehouse design; excellent communication; ability to translate problems into solutions.
SQL, AWS, Data warehousing, ETL, Python
1mo
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Senior Network Engineer
Atlanta or Washington
$120k-$165k/yr RemoteFull Time
6+ YOESix+ years in Cisco networks; experience with Palo Alto next-gen firewalls, GlobalProtect VPN, Prisma Access, and SD-WAN; Azure networking; scripting/automation; CCIE/CCNP Enterprise and Palo Alto NGFW Engineer certifications preferred.
Palo Alto, GlobalProtect, Prisma Access, SD-WAN, Cisco, Azure, Panorama, Python, Ansible
1mo
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Senior Research Engineer, Applied AI
Washington, District of Columbia, United States
$100k-$190k/yr OnsiteFull Time
5+ YOE5+ years building software, tools, or data systems; expertise in LLM-enabled systems; Python; experience in or with research, policy, government, or academic environments; familiarity with ChatGPT, Claude, Gemini, Grok.
Python, LLMs, Claude Code, Codex, ChatGPT, Claude, Gemini, Grok, SQL, R, Stata
2mo
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Senior Application Programmer/Developer (Secret Clearance and Full time On-site)
Washington, District of Columbia, United States
$135k-$145k/yr OnsiteFull Time
5+ YOEBachelor's degree in CS/IT or related field; 5+ years full-stack development; strong C#, Python, JavaScript/TypeScript; experience with .NET, SQL databases, HL7; federal/government contracting experience a plus.
C#, Python, JavaScript, TypeScript, .NET, SQL Server, Oracle, MySQL, HTML5, CSS3, jQuery, REST, SOAP, WSDL, XML, AWS, Azure DevOps, Jira, Palantir Foundry, Palantir Gotham, Git, CI/CD, HL7, EHR, HIPAA, Crystal Reports
4w
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Senior Full-Stack AI Application Engineer - iOS & VisionOS Emphasis
Lanham, Maryland, United States
HybridFull Time
5+ YOE5+ years full-stack development; 3+ years native iOS dev; Bachelor's in CS/Engineering or equivalent; VisionOS/spatial computing a plus.
Swift, SwiftUI, VisionOS, RealityKit, ARKit, CoreML, React, Next.js, Python, FastAPI, PostgreSQL, Redis, Cloud Services, Containerization, WebSockets
1w
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Application Software Developer (Full Stack Developer)
Herndon, Virginia, United States
RemoteFull Time
10+ YOEExperienced full stack developer with 10+ years in software development; 5+ years in DevSecOps and cloud-hosted apps; strong Java, Python, AWS, React/Angular; CI/CD with Jenkins, GitHub, Artifactory; Jira/Confluence; API, databases (MySQL, PostgreSQL).
Java, Python, AWS, React, Angular, Jenkins, GitHub, Artifactory, Jira, Confluence, MySQL, PostgreSQL, JBoss, Spark, Vault
1mo
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Senior Business Intelligence (BI) Developer (Columbia, MD, US)
Columbia, Maryland, United States
HybridFull Time
5+ YOE5-7 years as BI developer with data modeling, reporting (Power BI) and analytics experience.
Power BI, Salesforce Analytics, SQL, Python, Spark, R
1w
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Senior Engineer, Production
Arlington, Virginia, United States
OnsiteFull Time
3+ YOE3+ years production/ process engineering; advanced degree preferred; LNG or hydrocarbon experience; data tools such as Power BI, Python/SQL beneficial.
Excel, Power BI, Unisim, HYSYS, Python, SQL
2mo
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NLM Software Developer
Rockville, Maryland, United States
$105k-$132k/yr OnsiteFull Time
9+ YOE6+ years of software development experience; full SDLC; strong programming in C++, Python, Java, JavaScript, R; databases MySQL, PostgreSQL, MongoDB, ElasticSearch; Agile/DevSecOps; strong problem-solving and communication.
C++, Python, Java, JavaScript, R, Bash, MySQL, PostgreSQL, MongoDB, ElasticSearch, Jupyter Notebooks, GitHub, GitLab, CI/CD
5d
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Sr. Developer w/Analytics
Crystal City or United States
$100k-$150k/yr RemoteFull Time
5+ YOE5+ years software development experience with analytics; strong Python, SQL, data warehouses/lakes, Spark/Databricks, Elasticsearch; DHS Public Trust eligibility; US citizenship.
Python, SQL, PostgreSQL, Oracle, Data Warehouses, Data Lakes, Apache Spark, Databricks, Elasticsearch
1mo
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Principal Software Architect (Python)
Washington or Sarasota or Miami or Toronto
$160k-$195k/yr HybridFull Time
Expert-level Python development; RESTful APIs; OAuth2/OpenID Connect; relational DBs; distributed systems; Docker/Kubernetes; GitHub/CI/CD; strong communication and mentorship.
Python, FastAPI, SQLAlchemy, Jinja2, Flask, Gunicorn, GitHub, GitHub Actions, CI/CD, Docker, Kubernetes, OpenAPI, OAuth2, OpenID Connect, PostgreSQL, MySQL, RESTful APIs, Swagger
3w
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Software Engineer
Arlington or United States
$70k-$150k/yr RemoteFull Time
5+ YOE5–8+ years software development; healthcare domain experience; Agile; Python, React, FastAPI; REST APIs; CI/CD/DevSecOps; strong problem solving and communication.
Python, React, FastAPI, REST APIs, CI/CD, DevSecOps, VistA RPC, MUMPS, VistA, EHR
3w
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Senior Site Reliability Engineer (Arlington, VA)
Arlington or Chantilly
$180k-$220k/yr OnsiteFull Time
5+ YOE5+ years in Platform/DevOps/SRE; Top Secret clearance; Terraform/Ansible; Kubernetes; CI/CD; Python/Go/Bash; AWS; observability; incident response.
Terraform, Ansible, Kubernetes, Prometheus, Loki, Grafana, GitLab CI/CD, Jenkins, GitHub Actions, Python, Go, Bash, AWS, ELK, Datadog
1w
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Senior Scientist/Engineer
Fairfax or Alexandria or Arlington or Washington
$65-$180/hr RemotePart Time
5+ YOEPh.D. plus 5 years in hazardous waste remediation; strong writing, data analysis, problem-solving; experience with quantitative research and communicating to technical/non-technical audiences.
Mathematical Modeling, Data Analysis, Report Writing, Quantitative Research Tools, Python, R, MATLAB
1w
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Senior Digital Signals Processing and Algorithms Engineer
Arlington, Virginia, United States
HybridFull Time
5+ YOE5+ years DSP algorithm development for RF; C/C++ proficiency; geolocation experience; Python for prototyping; active Secret clearance or ability to obtain.
C/C++, Python, Software-defined radio, FPGA, HDL, Embedded systems, Spectral analysis, Digital filtering
2w
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Senior Site Reliability Engineer
Reston, Virginia, United States
$164k-$222k/yr HybridFull Time
10+ YOEBachelor's degree in computer science or related field; 10+ years sys/admin experience; strong Linux, Python, automation, and IaC skills; excellent communication; security knowledge; monitoring and DevOps tooling experience.
Ansible, Jenkins, Hashicorp Vault, Guardicore, Grafana, Splunk, Github, Jira, Confluence, oVirt, VMware, Squid, RedHat Enterprise Linux, ServiceNow, FreeIPA, Active Directory
13h
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Machine Learning Developer
Arlington County, Virginia, United States
HybridFull Time
5+ YOEExperience as ML developer; strong Python/Java/C#/R; ML frameworks TensorFlow/PyTorch/Scikit-Learn; NLP/Computer Vision; data preprocessing; Git; active Secret clearance.
TensorFlow, PyTorch, Scikit-Learn, Python, R, C#, Java, Git
1w
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Senior Systems Engineer #339
Washington, District of Columbia, United States
$103k-$174k/yr OnsiteFull Time
5+ YOEFive to eight years of relevant work experience; Secret security clearance; experience with storage, LAN/WAN/SAN, databases, troubleshooting, and Splunk; on-call rotation.
Splunk, Red Hat Enterprise Linux (RHEL), Ansible, Python, JavaScript, REST APIs, LAN/WAN, SAN
2w
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Senior Systems Engineer, DoW
Reston, Virginia, United States
OnsiteFull Time
10+ YOE10+ years pre-sales engineering; strong network security expertise; Federal DoD experience; excellent presentation skills; travel up to 50%.
TCP/IP, Routing, Switching, MPLS, VPN, SD-WAN, BGP, OSPF, IS-IS, ADVPN, Wired LAN, Wireless LAN, WAN, IPS, DLP, Antivirus, Web Filtering, NAC, RADIUS, LDAP, SAML, PKI, IPSEC/ESP, Firewall, Deep Packet Inspection, 802.1X, 802.1Q, SSH, SSL/TLS Decryption, Syslog, Encryption Ciphers, KVM, ESXi, HyperV, OpenStack, Docker, Kubernetes, Linux, Unix, Ansible, Terraform, YAML, JSON, NETCONF, OpenConfig, TCL, Perl, Python
6d
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Software Developer
Adelphi, Maryland, United States
OnsiteFull Time
10+ YOEBachelor's degree or 3 years of relevant experience; 10+ years software development; proficient in Python, PHP, JavaScript, C/C++, and/or Java; Elasticsearch/PostgreSQL; Linux; secure SDLC; ML/AI; web frameworks; Git/CI/CD; Atlassian tools; REST APIs; Docker/Kubernetes; ITIL Foundations; TS/SCI clearance.
Python, PHP, JavaScript, C/C++, Java, Elasticsearch, PostgreSQL, Docker, Kubernetes, Laravel, NodeJS, React, Angular, Git, BitBucket, CI/CD, JIRA, Confluence, RESTful API, REST API, Linux
5d
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Senior Signals Software Engineer
Columbia, Maryland, United States
OnsiteFull Time
7+ YOEBachelor's degree in CS or related field; 7+ years as Signals Software Engineer with RF focus; C++/Java; Linux exposure; signal processing.
C++, Java, Linux, Python, Git, ClearQuest, Trac, Subversion, Matlab, SIMULINK
HiringCafe market data
Senior Python Developer Jobs market signals in Leesburg, VA, US
These signals come from live HiringCafe job inventory, not a static article. Use them to compare the market, then open listings above to apply directly.
Open jobs
2,200+
Hiring companies
510+
Fresh sample
56% new in 30d
Salary visibility
45% show pay
Companies appearing in this market
ApplauseAST SpaceMobileBase-2 SolutionsEnvision Innovative SolutionsMarriott InternationalRealmOneSAICVMD Corp
Work location mix in visible results
Onsite: 43Hybrid: 24Remote: 18