
Craig Duhn engineered scalable backend and infrastructure solutions for the cisagov/XFD and cisagov/cool-dns-cyber.dhs.gov repositories, focusing on secure data synchronization, robust API development, and automated deployment. He integrated NIST and Redshift vulnerability data, modernized API endpoints using Python and Django, and enhanced observability with AWS ADOT and X-Ray. Craig refactored data models for maintainability, implemented Terraform-based infrastructure as code, and improved CI/CD reliability. His work on DNS management and certificate automation strengthened operational security, while code quality improvements and comprehensive testing increased deployment confidence. The depth of his contributions advanced both business value and technical resilience across environments.

October 2025 (Month: 2025-10) - cisagov/XFD monthly summary focusing on delivering scalable telemetry, reliable deployment automation, and quality improvements that drive business value. Key outcomes include robust ADOT layer deployment configuration, stronger observability, and CI/CD stabilization across the repository.
October 2025 (Month: 2025-10) - cisagov/XFD monthly summary focusing on delivering scalable telemetry, reliable deployment automation, and quality improvements that drive business value. Key outcomes include robust ADOT layer deployment configuration, stronger observability, and CI/CD stabilization across the repository.
September 2025 performance for cisagov/XFD focused on reliability, observability, and maintainability. Delivered core WAS synchronization improvements, enhanced Redshift scanning, and expanded test coverage; aligned endpoints with Pydantic v2 standards; enabled comprehensive OpenTelemetry observability (ADOT with X-Ray) and infrastructure refinements; and stabilized dependencies with frontend updates and a dependency lockfile. These changes improved data synchronization accuracy, scan throughput, and developer velocity while strengthening security and compliance posture.
September 2025 performance for cisagov/XFD focused on reliability, observability, and maintainability. Delivered core WAS synchronization improvements, enhanced Redshift scanning, and expanded test coverage; aligned endpoints with Pydantic v2 standards; enabled comprehensive OpenTelemetry observability (ADOT with X-Ray) and infrastructure refinements; and stabilized dependencies with frontend updates and a dependency lockfile. These changes improved data synchronization accuracy, scan throughput, and developer velocity while strengthening security and compliance posture.
Month 2025-08 performance summary for cisagov/XFD: Delivered key features for CVE data ingestion, indexing, and WAS synchronization, along with code quality improvements that enhance reliability and business visibility. The work focused on data quality, scalable ETL, and alignment with the Local Zone data model to improve vulnerability visibility and remediation timelines.
Month 2025-08 performance summary for cisagov/XFD: Delivered key features for CVE data ingestion, indexing, and WAS synchronization, along with code quality improvements that enhance reliability and business visibility. The work focused on data quality, scalable ETL, and alignment with the Local Zone data model to improve vulnerability visibility and remediation timelines.
July 2025 performance summary: Implemented a WasScanSummary-based daily WAS data aggregation for historical analytics in cisagov/XFD, improved code quality and reliability through lint and error handling enhancements, and strengthened DNS infrastructure and Terraform hygiene for cisagov/cool-dns-cyber.dhs.gov. These efforts improve historical analytics, reduce operational risk, and enhance maintainability of scanning telemetry and infrastructure as code.
July 2025 performance summary: Implemented a WasScanSummary-based daily WAS data aggregation for historical analytics in cisagov/XFD, improved code quality and reliability through lint and error handling enhancements, and strengthened DNS infrastructure and Terraform hygiene for cisagov/cool-dns-cyber.dhs.gov. These efforts improve historical analytics, reduce operational risk, and enhance maintainability of scanning telemetry and infrastructure as code.
June 2025: Delivered key enhancements to WAS handling and Qualys API integration in cisagov/XFD, improving reliability, maintainability, and business value. Refactored WAS findings flow, renamed frontend task, and removed temporary dev code. Strengthened Qualys integration with robust error handling, timeouts, and mypy-compliant dependencies. These changes reduce pipeline failures, speed up remediation, and provide clearer logs for security findings.
June 2025: Delivered key enhancements to WAS handling and Qualys API integration in cisagov/XFD, improving reliability, maintainability, and business value. Refactored WAS findings flow, renamed frontend task, and removed temporary dev code. Strengthened Qualys integration with robust error handling, timeouts, and mypy-compliant dependencies. These changes reduce pipeline failures, speed up remediation, and provide clearer logs for security findings.
May 2025 monthly summary for cisagov/XFD: Delivered notable increases in synchronization performance and infrastructure hygiene. Key CVE data synchronization improvements introduced pagination and since_date filtering to minimize processed data and latency, with updated data source tracking and removal of an unused API view parameter to streamline operation. Infrastructure and API key configuration updates improved key handling and maintainability, including header correctness, Terraform pre-commit checks, and cleanup of configuration and documentation. Fixed a critical Worker IAM KMS decrypt permission issue ensuring proper decryption and secure handling of sensitive data by the worker. These changes collectively enhance reliability, security, and operational efficiency.
May 2025 monthly summary for cisagov/XFD: Delivered notable increases in synchronization performance and infrastructure hygiene. Key CVE data synchronization improvements introduced pagination and since_date filtering to minimize processed data and latency, with updated data source tracking and removal of an unused API view parameter to streamline operation. Infrastructure and API key configuration updates improved key handling and maintainability, including header correctness, Terraform pre-commit checks, and cleanup of configuration and documentation. Fixed a critical Worker IAM KMS decrypt permission issue ensuring proper decryption and secure handling of sensitive data by the worker. These changes collectively enhance reliability, security, and operational efficiency.
April 2025 (2025-04) monthly summary for cisagov/XFD. The month focused on delivering robust data integration, API modernization, and tooling improvements while tightening security and CI reliability. Key features delivered include NIST integration and ORM updates, sync logic enhancements for was_finding, schema/model modernization to snake_case with related scan adjustments, and API/data model enhancements with camelCase refactors. CI hygiene improvements (pre-commit and build-worker) alongside dependency and lint fixes improved release velocity. API endpoint modeling and response standardization were aligned with updated data models; tests were updated to reflect route changes.
April 2025 (2025-04) monthly summary for cisagov/XFD. The month focused on delivering robust data integration, API modernization, and tooling improvements while tightening security and CI reliability. Key features delivered include NIST integration and ORM updates, sync logic enhancements for was_finding, schema/model modernization to snake_case with related scan adjustments, and API/data model enhancements with camelCase refactors. CI hygiene improvements (pre-commit and build-worker) alongside dependency and lint fixes improved release velocity. API endpoint modeling and response standardization were aligned with updated data models; tests were updated to reflect route changes.
Month: 2025-03 – cisagov/XFD delivered two key features to enhance vulnerability management and WAS findings workflows, with a focus on data integrity, automation, and developer productivity. NIST Vulnerability Data Integration adds backend support for CVE data (querying, inserting, formatting), updates to the scan schema, and task execution to enable NIST data ingestion; UI support for nist_update; and environment credential handling for the NIST API. WAS Findings Ingestion and Sync enables inserting Web Application Scanning findings and synchronizing them by fetching completed scans and their findings from external services, including API access configuration and UI support for WAS finding sync. No explicit major bug fixes were recorded in this period; the emphasis was on feature delivery, stability improvements, and end-to-end data workflows. Overall impact: strengthens third-party vulnerability data coverage, accelerates remediation workflows, and improves visibility and governance for security scans in XFD. Technologies/skills demonstrated: backend CVE data handling (query/insert/format), scan schema evolution, task orchestration, API integration for NIST/WAS, UI integration (nist_update, WAS finding sync), and environment credential management.
Month: 2025-03 – cisagov/XFD delivered two key features to enhance vulnerability management and WAS findings workflows, with a focus on data integrity, automation, and developer productivity. NIST Vulnerability Data Integration adds backend support for CVE data (querying, inserting, formatting), updates to the scan schema, and task execution to enable NIST data ingestion; UI support for nist_update; and environment credential handling for the NIST API. WAS Findings Ingestion and Sync enables inserting Web Application Scanning findings and synchronizing them by fetching completed scans and their findings from external services, including API access configuration and UI support for WAS finding sync. No explicit major bug fixes were recorded in this period; the emphasis was on feature delivery, stability improvements, and end-to-end data workflows. Overall impact: strengthens third-party vulnerability data coverage, accelerates remediation workflows, and improves visibility and governance for security scans in XFD. Technologies/skills demonstrated: backend CVE data handling (query/insert/format), scan schema evolution, task orchestration, API integration for NIST/WAS, UI integration (nist_update, WAS finding sync), and environment credential management.
February 2025 (2025-02) monthly summary highlighting key features, fixes, and impact across cisagov/XFD and cisagov/cool-dns-cyber.dhs.gov. Focused on business value, reliability, and deployment efficiency.
February 2025 (2025-02) monthly summary highlighting key features, fixes, and impact across cisagov/XFD and cisagov/cool-dns-cyber.dhs.gov. Focused on business value, reliability, and deployment efficiency.
January 2025 (cisagov/XFD) delivered four core features, hardened CI/CD, and tightened security governance, driving API accessibility, reliable maintenance tasks, and faster, safer deployments. Key features delivered: - API Exposure and Endpoint Configuration: Adds API endpoints exposure for Django app via api/functions.yaml, defines the ASGI handler, and enables CORS for base and sub-path requests. - Backend Background Tasks Scheduling: Centralizes backend scheduled tasks via functions.yaml, including a 5-minute scheduler, DB sync, user expiration checks, scans, and cache population for service/port/vulnerability/severity. - Security Policy Configuration: Adds .safety-policy.yml to standardize vulnerability handling, including CVSS-based ignore defaults and per-exclusion rules with reasons and expirations. - Codebase Maintenance, Linting, and CI/CD Workflow Enhancements: Batch improvements for cleanup, linting, and deployment tooling—removal of unused code and data, lint/config updates, TS/JS tooling adjustments, ESLint and TypeScript config changes, workflow/CI adjustments, and build script path/permission fixes. Major bugs fixed: - Resolved linting issues and removed dead code and deprecated scripts to stabilize CI. - Fixed build-worker.sh path/execution in backend.yml and updated related configuration. - Removed legacy components (e.g., stage-related code and populateCountiesCities) to reduce CI noise. Overall impact and accomplishments: - Improved API reach and reliability, with a clear path to integration; scheduled tasks ensure timely data freshness and consistency; security governance is now enforceable with automated policy handling; CI/CD hygiene reduces deployment risk and manual toil; and codebase health supports faster, safer iterations. Technologies/skills demonstrated: - Django, ASGI, API exposure via YAML; YAML-based task orchestration; Python, TypeScript, ESLint; CI/CD tooling and shell scripting; Git-based workflow discipline.
January 2025 (cisagov/XFD) delivered four core features, hardened CI/CD, and tightened security governance, driving API accessibility, reliable maintenance tasks, and faster, safer deployments. Key features delivered: - API Exposure and Endpoint Configuration: Adds API endpoints exposure for Django app via api/functions.yaml, defines the ASGI handler, and enables CORS for base and sub-path requests. - Backend Background Tasks Scheduling: Centralizes backend scheduled tasks via functions.yaml, including a 5-minute scheduler, DB sync, user expiration checks, scans, and cache population for service/port/vulnerability/severity. - Security Policy Configuration: Adds .safety-policy.yml to standardize vulnerability handling, including CVSS-based ignore defaults and per-exclusion rules with reasons and expirations. - Codebase Maintenance, Linting, and CI/CD Workflow Enhancements: Batch improvements for cleanup, linting, and deployment tooling—removal of unused code and data, lint/config updates, TS/JS tooling adjustments, ESLint and TypeScript config changes, workflow/CI adjustments, and build script path/permission fixes. Major bugs fixed: - Resolved linting issues and removed dead code and deprecated scripts to stabilize CI. - Fixed build-worker.sh path/execution in backend.yml and updated related configuration. - Removed legacy components (e.g., stage-related code and populateCountiesCities) to reduce CI noise. Overall impact and accomplishments: - Improved API reach and reliability, with a clear path to integration; scheduled tasks ensure timely data freshness and consistency; security governance is now enforceable with automated policy handling; CI/CD hygiene reduces deployment risk and manual toil; and codebase health supports faster, safer iterations. Technologies/skills demonstrated: - Django, ASGI, API exposure via YAML; YAML-based task orchestration; Python, TypeScript, ESLint; CI/CD tooling and shell scripting; Git-based workflow discipline.
November 2024 focused on delivering robust DNS infrastructure for the crossfeed application and stabilizing certificate issuance workflows. Key work includes implementing Crossfeed DNS integration infrastructure with A, AAAA, TXT, and CAA records, plus an API Gateway alias for api.integration, accompanied by expanded documentation and README updates. In addition, the DNS records were reorganized and clarified to improve maintainability and reduce risk during deployments. The staging environment was hardened for automated Let’s Encrypt certificate issuance by updating DNS TXT values. These efforts improve deployment reliability, security posture, and operational scalability while showcasing Terraform-based IaC, AWS Route 53, API Gateway, and Let’s Encrypt automation.
November 2024 focused on delivering robust DNS infrastructure for the crossfeed application and stabilizing certificate issuance workflows. Key work includes implementing Crossfeed DNS integration infrastructure with A, AAAA, TXT, and CAA records, plus an API Gateway alias for api.integration, accompanied by expanded documentation and README updates. In addition, the DNS records were reorganized and clarified to improve maintainability and reduce risk during deployments. The staging environment was hardened for automated Let’s Encrypt certificate issuance by updating DNS TXT values. These efforts improve deployment reliability, security posture, and operational scalability while showcasing Terraform-based IaC, AWS Route 53, API Gateway, and Let’s Encrypt automation.
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