google/meridian
Dec 2024 – Oct 2025
9 Months active
Languages Used
PythonSQLHTMLJavaScriptMarkdownJAXTensorFlow
Technical Skills
Backend DevelopmentData AnalysisData EngineeringData ModelingData ValidationMachine Learning
Andy Tan
PROFILE
Andy Tan
Andy Tan developed core data ingestion, analytics, and backend abstraction features for the google/meridian repository, focusing on scalable, reproducible modeling and visualization workflows. He engineered a unified backend layer supporting both TensorFlow and JAX, enabling flexible numerical operations and probabilistic sampling. His work included robust data validation, time-aware analytics, and dynamic charting using Python, JAX, and Vega-Lite, ensuring reliable geospatial-temporal evaluation and organic media analysis. Andy addressed edge cases in spend analytics, improved serialization and testing, and maintained code quality through refactoring and documentation. His contributions deepened backend flexibility and data integrity, supporting maintainable, cross-backend machine learning pipelines.
Overall Statistics
Feature vs Bugs
78%Features
Repository Contributions
64Total
Bugs
4
Commits
64
Features
14
Lines of code
14,201
Activity Months9
Your Network
4168 people
Work History
October 2025
2 Commits • 2 Features
Oct 1, 2025Performance summary for 2025-10: Delivered JAX backend integration for prior_sampler in google/meridian, enabling stateful RNG via PRNGKeys and ensuring proper handling of JAX's stateless RNG within sampling methods; updated tests to reflect the switch from error to warning for set_random_seed in JAX. Also performed code formatting and readability cleanup in model.py and model_test.py to improve maintainability, with autoformatting committed. Overall, these changes improve reproducibility, reliability of sampling under JAX, and code quality for future enhancements.
2 Commits • 2 Features
Oct 1, 2025Performance summary for 2025-10: Delivered JAX backend integration for prior_sampler in google/meridian, enabling stateful RNG via PRNGKeys and ensuring proper handling of JAX's stateless RNG within sampling methods; updated tests to reflect the switch from error to warning for set_random_seed in JAX. Also performed code formatting and readability cleanup in model.py and model_test.py to improve maintainability, with autoformatting committed. Overall, these changes improve reproducibility, reliability of sampling under JAX, and code quality for future enhancements.
October 2025
September 2025
18 Commits • 2 Features
Sep 1, 20252025-09 monthly performance: Delivered cross-backend Meridian consolidation with JAX support, enabling unified backend usage across visualization, testing, and sampling. Introduced backend-agnostic utilities and RNG handling to ensure consistent, cross-backend operation and reproducibility. Implemented runtime backend selection via MERIDIAN_BACKEND and serialization compatibility across components, simplifying cross-backend experiments and deployments. Enhanced Adstock and Hill calculations for cross-backend compatibility, including JAX boolean masking and fixed channel alignment. Expanded testing to validate both TensorFlow and JAX backends and adjusted tolerances to accommodate backend-specific behavior. Improved code quality and data serialization (e.g., prior_distributions and related utilities) to support stable, repeatable results across environments.
September 2025
18 Commits • 2 Features
Sep 1, 20252025-09 monthly performance: Delivered cross-backend Meridian consolidation with JAX support, enabling unified backend usage across visualization, testing, and sampling. Introduced backend-agnostic utilities and RNG handling to ensure consistent, cross-backend operation and reproducibility. Implemented runtime backend selection via MERIDIAN_BACKEND and serialization compatibility across components, simplifying cross-backend experiments and deployments. Enhanced Adstock and Hill calculations for cross-backend compatibility, including JAX boolean masking and fixed channel alignment. Expanded testing to validate both TensorFlow and JAX backends and adjusted tolerances to accommodate backend-specific behavior. Improved code quality and data serialization (e.g., prior_distributions and related utilities) to support stable, repeatable results across environments.
August 2025
18 Commits • 2 Features
Aug 1, 2025August 2025 monthly summary: Implemented foundational backend abstraction enabling multi-backend support (JAX, TensorFlow) across Meridian core modules and centralized backend ops under meridian.backend, enhancing testability, maintainability, and future extensibility. Expanded analytics capabilities with Organic RF support across Analyzer, Hill curves, and plotting, with docs and tests updated. Other notable improvements include deterministic RNG seeding in prior_sampler and migration of components to the backend API (backend.Tensor usage, etc.).
18 Commits • 2 Features
Aug 1, 2025August 2025 monthly summary: Implemented foundational backend abstraction enabling multi-backend support (JAX, TensorFlow) across Meridian core modules and centralized backend ops under meridian.backend, enhancing testability, maintainability, and future extensibility. Expanded analytics capabilities with Organic RF support across Analyzer, Hill curves, and plotting, with docs and tests updated. Other notable improvements include deterministic RNG seeding in prior_sampler and migration of components to the backend API (backend.Tensor usage, etc.).
August 2025
July 2025
1 Commits • 1 Features
Jul 1, 2025Monthly summary for 2025-07 focusing on business value and technical achievements in google/meridian.
July 2025
1 Commits • 1 Features
Jul 1, 2025Monthly summary for 2025-07 focusing on business value and technical achievements in google/meridian.
April 2025
12 Commits • 3 Features
Apr 1, 2025April 2025 monthly summary focused on delivering richer channel insights, expanding organic media analysis, and ensuring release hygiene for Meridian. The work emphasized business value through time-aware visualizations, cross-channel comparisons, and maintainable release processes.
12 Commits • 3 Features
Apr 1, 2025April 2025 monthly summary focused on delivering richer channel insights, expanding organic media analysis, and ensuring release hygiene for Meridian. The work emphasized business value through time-aware visualizations, cross-channel comparisons, and maintainable release processes.
April 2025
March 2025
5 Commits • 2 Features
Mar 1, 2025March 2025 — google/meridian: Implemented data validation and integrity improvements, enhanced analytics capabilities, and improved visualization robustness. Focus areas included data integrity for geometry and coordinates, time-aware metrics for contribution analytics, and responsive Vega charts to fit dynamic containers. These changes increase reliability of data processing, enable time-based insights, and improve visualization UX for end users and business stakeholders.
March 2025
5 Commits • 2 Features
Mar 1, 2025March 2025 — google/meridian: Implemented data validation and integrity improvements, enhanced analytics capabilities, and improved visualization robustness. Focus areas included data integrity for geometry and coordinates, time-aware metrics for contribution analytics, and responsive Vega charts to fit dynamic containers. These changes increase reliability of data processing, enable time-based insights, and improve visualization UX for end users and business stakeholders.
February 2025
1 Commits
Feb 1, 2025February 2025 monthly summary focusing on bug fixes and stability improvements for google/meridian. Key contributions include addressing a critical edge-case in Budget Optimizer and strengthening test coverage, delivering business value through more reliable spend analytics.
1 Commits
Feb 1, 2025February 2025 monthly summary focusing on bug fixes and stability improvements for google/meridian. Key contributions include addressing a critical edge-case in Budget Optimizer and strengthening test coverage, delivering business value through more reliable spend analytics.
February 2025
January 2025
1 Commits
Jan 1, 2025January 2025 monthly summary focused on stabilizing national model evaluation in google/meridian by fixing a holdout filtering index bug, improving 1D time indexing handling, and expanding test coverage. No new features shipped this month; main work centered on bug fix with direct business value in model reliability and data integrity.
January 2025
1 Commits
Jan 1, 2025January 2025 monthly summary focused on stabilizing national model evaluation in google/meridian by fixing a holdout filtering index bug, improving 1D time indexing handling, and expanding test coverage. No new features shipped this month; main work centered on bug fix with direct business value in model reliability and data integrity.
December 2024
6 Commits • 2 Features
Dec 1, 2024December 2024 monthly summary for google/meridian focusing on delivering end-to-end data ingestion and analysis capabilities, stabilizing data integrity, and enabling geospatial-temporal evaluation at scale.
6 Commits • 2 Features
Dec 1, 2024December 2024 monthly summary for google/meridian focusing on delivering end-to-end data ingestion and analysis capabilities, stabilizing data integrity, and enabling geospatial-temporal evaluation at scale.
December 2024
Activity
Loading activity data...
Quality Metrics
Correctness96.6%
Maintainability93.2%
Architecture92.8%
Performance84.4%
AI Usage20.2%
Skills & Technologies
Programming Languages
HTMLJAXJavaScriptMarkdownPythonSQLTensorFlow
Technical Skills
API DesignAPI IntegrationAbstraction LayerAltairBackend DevelopmentBackend IntegrationCode AbstractionCode FormattingCode RefactoringConditional LogicConfigurationData AnalysisData EngineeringData ModelingData Science
Repositories Contributed To
Overview of all repositories you've contributed to across your timeline