March 2026 monthly summary for iza-institute-of-labor-economics/gettsim: Deliveries focused on API-stable features, reliability, and workflow automation that support business operations and downstream teams. Key features delivered include piecewise polynomial handling improvements with API alignment to GEP-08 and clearer YAML structures; introduction of a DAGs tool enabling DAG-based workflows; documentation and dependency consistency improvements; and release readiness work for v1.2.

February 2026 — Delivered two high-value features in iza-institute-of-labor-economics/gettsim with strong emphasis on usability, maintainability, and build reliability. Key results: 1) Piecewise Polynomial Specification Interface Enhancement: refactored to interval notation, simplifying interval definitions, improving usability, and strengthening internal representation and validation. 2) Configuration Standardization and Dependency Harmonization (pyproject.toml): standardized configuration across projects to improve consistency, maintainability, and build processes, including dependency updates. No standalone bug fixes were recorded this month; efforts targeted reducing future defects through better APIs and configuration governance. Business impact: faster onboarding for new contributors, fewer misconfigurations, more predictable builds, and more robust handling of piecewise-function definitions. Technologies/skills demonstrated: Python refactoring, interface design, interval notation adoption, cross-project configuration management, and collaborative development (co-authored commits).

January 2026: Delivered four key capabilities within iza-institute-of-labor-economics/gettsim, fixed critical CI/testing issues, prepared GETTSIM for the 1.1 release, clarified the Entgeltpunkte API, and expanded DAG visualization features. Emphasis on reliability, faster feedback cycles, clearer API/docs, and visualization flexibility enabled downstream teams to ship features with confidence and better integrate with the broader ttsim ecosystem.

December 2025 monthly summary focusing on key achievements in the iza-institute-of-labor-economics/gettsim repository. Delivered CI/test reliability improvements and type-safety enhancements that reduce flakiness and speed up safe deployments across the dev-gettsim workspace.

September 2025 monthly summary for iza-institute-of-labor-economics/gettsim: Focused on stabilizing vectorization policy handling in Gemeinschaft calculations to improve correctness and reliability for Bedarfsgemeinschaft and Einstandsgemeinschaft computations. Delivered a targeted bug fix with clear policy defaults and minor type-hint improvements to reduce edge-case errors.

August 2025 monthly summary focusing on delivering stable release readiness, documentation, API consistency, and targeted tax-logic fixes across two repositories. The work emphasized packaging integrity, maintainability, and customer-facing improvements, aligning with business value of reliable releases and accurate computations.

July 2025 monthly summary for development focused on architectural modernization of Gettsim and packaging improvements for ttsim-backend, with a strong emphasis on reliability, maintainability, and distribution readiness. Highlights include major framework migration, internal restructuring, enhanced error handling, data integrity fixes, and packaging automation for broader deployment.

March 2025 — Delivered GETTSIM GEP 6: a DAG-based unified architecture with policy namespaces and conditional decorators, including parameter pre-processing for flexible and robust policy function invocation. This architectural upgrade reduces integration risk, accelerates feature delivery, and improves testability and maintainability, setting the stage for modular policy modules.