February 2026 (2026-02) monthly summary focusing on delivering targeted API improvements, deprecations, and security hardening across multiple services. The month focused on removing technical debt, clarifying documentation, and strengthening authentication controls, while enabling more flexible validation workflows in sandbox environments. Overall, these changes improve compliance, partner integration readiness, and developer experience, with clear traceability to commit-level changes.

January 2026 monthly summary for the dev team. Delivered regulatory-aligned API simplifications and data-model refinements across three services to support 2026-27 tax-year handling. Key activities included removal of electricChargePointAllowance from property retrieval and self-employment response schemas, documentation changes for BSAS API field removal, and the introduction of max tax year validation and API versioning across losses APIs. These changes reduce surface area, improve data integrity, and enable phased rollout while maintaining client interoperability.

December 2025: Delivered targeted API enhancements and data integrity fixes across HMRC services. Key features include exposing transitionProfit fields in IncomeTax API, and adding Tax API v18 endpoints for student loan benefits and relief investments; major bug fix corrected JSON structure for foreign property details. These changes improve accuracy, coverage, and client onboarding for 2025-26.

November 2025 monthly summary for hmrc/individual-calculations-api. Focused on deprecating the social-enterprise-investment field to align with updated data model and future removal. Delivered groundwork across configuration, JSON schema, feature flags, and API responses to prepare for removal in future releases; no major bugs fixed this month; laid foundations for API surface simplification and governance to support smoother releases.

October 2025 focused on strengthening API documentation, improving POA clarity, and enabling regulatory-aligned Def2 schema support. Key outcomes include a version bump to API docs, clarified business ID format and POA submission prerequisite, and Def2 schema support for PPD overrides with dynamic tax-year handling for 2025-26+, along with new validation rules and data models. These changes reduce integration risk, accelerate downstream adoption, and position the teams for upcoming regulatory migrations.

September 2025 monthly summary focused on API governance, migration readiness, and documentation. Delivered auditability improvements for foreign property data, implemented feature-switch guided routing for CGT endpoints, and updated policy docs to reflect tax-year restrictions. No major bug fixes were logged this period; all changes reinforce reliability, compliance, and traceability across repos.

August 2025 monthly summary: Delivered significant API enhancements across two repositories, focusing on business value and technical robustness. Key features include Late Accounting Date Rule (LADR) management with new disapply/withdraw request models and a Withdraw LADR controller with integration tests and routes, plus generalization of the tax year parameter for Retrieve Accounting Type to remove the minimum tax year restriction. Major bug fix: Retrieve Accounting Type no longer rejects valid tax years due to the min-tax-year constraint, with observability improvements added via endpoint logging. Overall impact: expanded API capabilities for tax-year queries, streamlined LADR workflows, improved data integrity, and enhanced test coverage and changelog traceability. Technologies/skills demonstrated: API design and modeling, REST controllers, integration testing, Git-based delivery, changelog maintenance, cross-repo collaboration.

Concise monthly summary for July 2025 focusing on business value and technical achievements across four repositories. Key features delivered, major bugs fixed, impact, and skills demonstrated.

June 2025 monthly summary focusing on API changelog, documentation improvements, and deprecation cleanup across two HMRC APIs. The month delivered concrete changelog entries for new endpoints, clarified error handling in documentation, and removed an obsolete endpoint to reduce surface area and support overhead. The work emphasizes business value through clearer developer guidance, smoother integration experiences, and reduced risk from deprecated functionality.

Month: 2025-05. This report covers the hmrc/individual-losses-api and hmrc/individual-calculations-api workstreams, focusing on reliability, platform migration, and new API capabilities. May delivered HIP-based error handling improvements, cross-version endpoint migrations, and the initial rollout of Version 6 API components.

March 2025: Delivered Zero Adjustments support for BSAS in hmrc/self-assessment-bsas-api, covering foreign property and UK property scenarios. Introduced a new zeroAdjustments field, refactored data models and response handling to support zero-adjustment cases, and updated API configuration documentation. Also renamed the ZERO_ADJUSTMENTS scenario to UK_PROPERTY_ZERO_ADJUSTMENTS for clearer, more descriptive simulations. This work enhances configurability, accuracy, and test coverage for property-related BSAS, enabling more precise business reporting and reducing integration risk.

February 2025 monthly summary focusing on business value and technical achievements across two HMRC services. This month featured targeted CI/build improvements and API quality fixes that reduce risk, improve developer productivity, and strengthen API reliability for downstream integrations. Key outcomes: - CI/Build tooling improvements in hmrc/individual-calculations-api to improve artifact retrieval and build reliability by updating artifact repository configurations and bumping the sbt-auto-build plugin to the latest version. - OpenAPI Specification formatting fix in hmrc/self-employment-business-api to ensure correct error modeling by adding a missing 400 response in the OAS, aligning with API error handling expectations. - Amendment period validation rule introduced (OUTSIDE_AMENDMENT_WINDOW) to prevent submissions outside the allowed amendment window; integrated into create/amend annual submission and delete annual submission services; API config updated with appropriate error responses. Impact and business value: The changes reduce build-time friction, improve reliability of artifact retrieval, and enforce business rules at the API boundary to prevent invalid submissions. The API definitions now better reflect error scenarios, enabling clearer consumer guidance and fewer runtime errors. These improvements collectively decrease support and incident costs while enabling faster, safer changes to submission workflows. Technologies/skills demonstrated: sbt/build tooling, artifact repository configuration, OpenAPI specification management, API validation and error modeling, and cross-service configuration governance.

January 2025 monthly overview focused on improving API maintainability, consistency, and versioning across two services, delivering tangible business value and enabling faster future iterations.

December 2024 monthly summary focusing on key outcomes across three repositories. Delivered targeted improvements in test reliability, cross-service code reuse via a shared library, and expanded API capabilities with v7.0 for Individual Calculations. These efforts collectively reduce maintenance overhead, speed service delivery, and enhance tax calculation management.

November 2024: Focused on API documentation and OpenAPI spec alignment for the Brought Forward Losses Retrieve endpoint. Key work included updating the OpenAPI spec to reflect the 2025-26 deprecation for UK-property-FHL and foreign-property-FHL income sources, correcting test data headers to UK_PROPERTY_FHL for accurate loss type simulation, and clarifying in docs that retrieval requires both a National Insurance number and a Loss ID. No major bugs fixed this month; improvements concentrated on developer guidance and API correctness to reduce integration risk and future support needs. Overall impact includes clearer integration guidance, improved maintainability, and alignment with the tax-year policy. Technologies/skills demonstrated: OpenAPI/Swagger, API documentation, test data validation, versioned releases, MTDSA issue tracking (MTDSA-24567, MTDSA-27439).