
Petar developed and maintained the open-jii platform for the Jan-IngenHousz-Institute, delivering robust infrastructure, data, and application features over 13 months. He architected scalable AWS and Databricks environments using Terraform and Python, enabling secure IoT data ingestion, automated experiment provisioning, and real-time analytics. Petar implemented unified authentication, modular CI/CD pipelines, and advanced data visualization, integrating technologies like TypeScript, React, and SQL. His work included backend API evolution, observability improvements, and rigorous security updates, all within a monorepo structure. The depth of his engineering ensured reliable deployments, maintainable codebases, and efficient data workflows, directly supporting research and analytics objectives.

February 2026 monthly summary for Jan-IngenHousz-Institute/open-jii focused on Databricks infrastructure modernization and provisioning improvements. Delivered a monorepo-based turborepo setup with Databricks asset bundles and automated deployment workflows, significantly boosting deployment reliability. Provisioning throughput was increased by raising max_concurrent_runs from 1 to 5, enabling higher production throughput. Refactored the data layer to centralize provisioning workflows into a unified schema, improving query capabilities and reducing operational overhead. No documented major bugs fixed this month; efforts emphasized feature delivery, architectural modernization, and scalability to support growing workloads.
February 2026 monthly summary for Jan-IngenHousz-Institute/open-jii focused on Databricks infrastructure modernization and provisioning improvements. Delivered a monorepo-based turborepo setup with Databricks asset bundles and automated deployment workflows, significantly boosting deployment reliability. Provisioning throughput was increased by raising max_concurrent_runs from 1 to 5, enabling higher production throughput. Refactored the data layer to centralize provisioning workflows into a unified schema, improving query capabilities and reducing operational overhead. No documented major bugs fixed this month; efforts emphasized feature delivery, architectural modernization, and scalability to support growing workloads.
January 2026 highlights for Jan-IngenHousz-Institute/open-jii focusing on secure, observable, and scalable platform improvements. Delivered a Unified Authentication System migration to Better Auth with passwordless OTP and ORCID enhancements, including immediate sign-in state syncing, ORCID provider fixes, and robust error handling across web and server lambdas. Implemented observability and notifications enhancements with structured JSON logs via Pino, centralized transactional email rendering, and improved error codes. Strengthened provisioning and deployment workflows: experiment provisioning now tracks pipeline_id and schema_name; analytics config updated with a separate UI host and env var handling integrated into GitHub Actions builds. Backend reliability improvements include rate_limit schema change (last_request from timestamp to bigint) and new public URL env vars for dev/prod configurations. Maintenance activities included dependency updates (pnpm lock, expo-secure-store) and temporary UI changes to disable AppSidebar search to stabilize the release. Technologies/skills demonstrated: OAuth/Better Auth integration, ORCID provisioning, serverless lambda adjustments, structured logging with Pino, CI/CD with GitHub Actions, analytics integration (PostHog), backend schema migrations, and dependency management.
January 2026 highlights for Jan-IngenHousz-Institute/open-jii focusing on secure, observable, and scalable platform improvements. Delivered a Unified Authentication System migration to Better Auth with passwordless OTP and ORCID enhancements, including immediate sign-in state syncing, ORCID provider fixes, and robust error handling across web and server lambdas. Implemented observability and notifications enhancements with structured JSON logs via Pino, centralized transactional email rendering, and improved error codes. Strengthened provisioning and deployment workflows: experiment provisioning now tracks pipeline_id and schema_name; analytics config updated with a separate UI host and env var handling integrated into GitHub Actions builds. Backend reliability improvements include rate_limit schema change (last_request from timestamp to bigint) and new public URL env vars for dev/prod configurations. Maintenance activities included dependency updates (pnpm lock, expo-secure-store) and temporary UI changes to disable AppSidebar search to stabilize the release. Technologies/skills demonstrated: OAuth/Better Auth integration, ORCID provisioning, serverless lambda adjustments, structured logging with Pino, CI/CD with GitHub Actions, analytics integration (PostHog), backend schema migrations, and dependency management.
December 2025: The team delivered security, reliability, and UX improvements across the Open JII platform, with meaningful experimentation and a strong focus on data-centric features. Notable initiatives included a Next.js upgrade to mitigate a critical RCE vulnerability, infrastructure enhancements (docs CDN and PostHog vars) for production reliability and observability, and new data tooling such as annotations and raw payload ingestion. We also progressed data exploration capabilities with reworked table data pages & API and columnar sorting, plus data safety with scheduled raw_data backups. Several UX iterations (platform navigation/dashboard overhaul) were explored with a controlled rollback to preserve stability, while CI/CD and workflow improvements reduced operational risk and technical debt. Businesses value: security hardened, more reliable deployments, and improved data analytics usability.
December 2025: The team delivered security, reliability, and UX improvements across the Open JII platform, with meaningful experimentation and a strong focus on data-centric features. Notable initiatives included a Next.js upgrade to mitigate a critical RCE vulnerability, infrastructure enhancements (docs CDN and PostHog vars) for production reliability and observability, and new data tooling such as annotations and raw payload ingestion. We also progressed data exploration capabilities with reworked table data pages & API and columnar sorting, plus data safety with scheduled raw_data backups. Several UX iterations (platform navigation/dashboard overhaul) were explored with a controlled rollback to preserve stability, while CI/CD and workflow improvements reduced operational risk and technical debt. Businesses value: security hardened, more reliable deployments, and improved data analytics usability.
November 2025 (2025-11) stabilization of the Experiment Data Table by disabling bulk actions and row selection to prevent broken submissions while backend support is incomplete. Data export functionality remains intact, preserving core data workflows and reducing user friction.
November 2025 (2025-11) stabilization of the Experiment Data Table by disabling bulk actions and row selection to prevent broken submissions while backend support is incomplete. Data export functionality remains intact, preserving core data workflows and reducing user friction.
October 2025 performance summary for Jan-IngenHousz-Institute/open-jii. This period focused on delivering high-value features for experimentation, improving user experience for data entry, hardening security, and tightening deployment reliability. Key outcomes include advanced visualization and macro-enabled experiment flows, a reusable multi-step WizardForm, structured rendering for nested experiment data, and infrastructure upgrades that simplify operations while enhancing security and compliance. Corresponding bug fixes improved stability across migrations and authentication surfaces.
October 2025 performance summary for Jan-IngenHousz-Institute/open-jii. This period focused on delivering high-value features for experimentation, improving user experience for data entry, hardening security, and tightening deployment reliability. Key outcomes include advanced visualization and macro-enabled experiment flows, a reusable multi-step WizardForm, structured rendering for nested experiment data, and infrastructure upgrades that simplify operations while enhancing security and compliance. Corresponding bug fixes improved stability across migrations and authentication surfaces.
September 2025 highlights for Jan-IngenHousz-Institute/open-jii: delivered production, data, and analytics improvements across the stack to shorten release cycles, scale data processing, and strengthen security communications. The month focused on optimizing builds, expanding ingestion pipelines, rolling out a macro-domain model across services, and enhancing data visualization for faster decision-making.
September 2025 highlights for Jan-IngenHousz-Institute/open-jii: delivered production, data, and analytics improvements across the stack to shorten release cycles, scale data processing, and strengthen security communications. The month focused on optimizing builds, expanding ingestion pipelines, rolling out a macro-domain model across services, and enhancing data visualization for faster decision-making.
August 2025 monthly summary for Jan-IngenHousz-Institute/open-jii: Delivered significant product and platform improvements across authentication, Databricks integration, CI/CD, and maintenance. Key outcomes include streamlined user onboarding with non-disruptive registration, a modular Databricks architecture for improved security and scalability, a hardened and faster CI/CD pipeline, consolidated dependency versions for easier maintenance, and strengthened test stability and repository hygiene. These changes reduce onboarding friction, increase security and reliability, and enable faster release cycles and future updates.
August 2025 monthly summary for Jan-IngenHousz-Institute/open-jii: Delivered significant product and platform improvements across authentication, Databricks integration, CI/CD, and maintenance. Key outcomes include streamlined user onboarding with non-disruptive registration, a modular Databricks architecture for improved security and scalability, a hardened and faster CI/CD pipeline, consolidated dependency versions for easier maintenance, and strengthened test stability and repository hygiene. These changes reduce onboarding friction, increase security and reliability, and enable faster release cycles and future updates.
July 2025 monthly summary for Jan-IngenHousz-Institute/open-jii. Key features delivered include: (1) Protocols CRUD Management with full backend APIs, a database migration for a protocols table, and a web UI featuring a JSON code editor. (2) Databricks Experiment Status Webhook providing a secure HMAC-authenticated channel to auto-update provisioning status, plus an accompanying Databricks notebook to send updates. (3) Auth System Refactor and Type Consolidation standardizing the User type, centralizing auth definitions, and updating core dependencies to improve type safety and module organization.
July 2025 monthly summary for Jan-IngenHousz-Institute/open-jii. Key features delivered include: (1) Protocols CRUD Management with full backend APIs, a database migration for a protocols table, and a web UI featuring a JSON code editor. (2) Databricks Experiment Status Webhook providing a secure HMAC-authenticated channel to auto-update provisioning status, plus an accompanying Databricks notebook to send updates. (3) Auth System Refactor and Type Consolidation standardizing the User type, centralizing auth definitions, and updating core dependencies to improve type safety and module organization.
June 2025 delivered broad platform improvements across CI/CD, infrastructure, data APIs, and user experience, prioritizing automation, security, and scalable data access. Key business value includes faster and more reliable deployments, stronger security posture, accessible experiment data via API, and improved session UX and SEO. The team also addressed a critical risk by removing scripts from include directives to prevent unintended execution.
June 2025 delivered broad platform improvements across CI/CD, infrastructure, data APIs, and user experience, prioritizing automation, security, and scalable data access. Key business value includes faster and more reliable deployments, stronger security posture, accessible experiment data via API, and improved session UX and SEO. The team also addressed a critical risk by removing scripts from include directives to prevent unintended execution.
May 2025 delivered a robust set of security, data, and platform enhancements that enable secure, scalable experimentation and cross-domain frontend deployments while tightening backend reliability. Key outcomes include a unified authentication layer, enriched experiment management with modern data-fetching, IoT device integration, cross-origin support, Databricks-enabled experiment workflows, and ongoing improvements to API design and type-safety.
May 2025 delivered a robust set of security, data, and platform enhancements that enable secure, scalable experimentation and cross-domain frontend deployments while tightening backend reliability. Key outcomes include a unified authentication layer, enriched experiment management with modern data-fetching, IoT device integration, cross-origin support, Databricks-enabled experiment workflows, and ongoing improvements to API design and type-safety.
April 2025 monthly summary for Jan-IngenHousz-Institute/open-jii focusing on observability enhancements, CI/CD modernization, infrastructure resilience, module consolidation, backend API evolution, and containerization. Delivered a cohesive set of improvements across AWS, Terraform, Databricks, and backend services, with an emphasis on business value, reliability, and developer experience.
April 2025 monthly summary for Jan-IngenHousz-Institute/open-jii focusing on observability enhancements, CI/CD modernization, infrastructure resilience, module consolidation, backend API evolution, and containerization. Delivered a cohesive set of improvements across AWS, Terraform, Databricks, and backend services, with an emphasis on business value, reliability, and developer experience.
March 2025 performance summary for Jan-IngenHousz-Institute/open-jii. Delivered end-to-end data platform enhancements including a new MultispeQ MQTT-interfacing CLI (MMI) with continuous measurement publishing and plant metadata, expanded Delta Live Tables (DLT) ELT pipelines, and orchestration. Implemented comprehensive CI/CD automation for PRs and multi-environment deployments, plus centralized Databricks workspace setup. Achieved Unity Catalog integration with S3-backed metastore and secured data access, and published governance-focused documentation and ADRs. Introduced an Agile User Story Template to standardize issue creation. These efforts improve data ingestion reliability, real-time processing capabilities, governance, and scalable deployment, driving faster feature delivery and higher data quality.
March 2025 performance summary for Jan-IngenHousz-Institute/open-jii. Delivered end-to-end data platform enhancements including a new MultispeQ MQTT-interfacing CLI (MMI) with continuous measurement publishing and plant metadata, expanded Delta Live Tables (DLT) ELT pipelines, and orchestration. Implemented comprehensive CI/CD automation for PRs and multi-environment deployments, plus centralized Databricks workspace setup. Achieved Unity Catalog integration with S3-backed metastore and secured data access, and published governance-focused documentation and ADRs. Introduced an Agile User Story Template to standardize issue creation. These efforts improve data ingestion reliability, real-time processing capabilities, governance, and scalable deployment, driving faster feature delivery and higher data quality.
February 2025: Delivered a scalable AWS infrastructure for IoT data and static site hosting, with secure CI/CD and repeatable tooling. Achievements: 1) IoT Platform: Terraform modules for AWS IoT Core, Timestream, and Kinesis, plus AsyncAPI topic definitions to standardize device data schemas; 2) Static site hosting: S3 + CloudFront with OAI-to-OAC access-control migration and CloudFront ARN exposure for integration; 3) Databricks Managed Workspace (MWS): Terraform-based provisioning (VPC, S3 root storage, and workspace) to enable end-to-end deployment; 4) CI/CD security: AWS OIDC provider and deployment role for GitHub Actions with provider docs; 5) Foundations: OpenTofu baseline for AWS resources with state management (S3 locking) and accompanying infrastructure docs. Impact: faster, secure deployments; improved data routing and schema consistency; reduced operational toil and improved auditability and governance.
February 2025: Delivered a scalable AWS infrastructure for IoT data and static site hosting, with secure CI/CD and repeatable tooling. Achievements: 1) IoT Platform: Terraform modules for AWS IoT Core, Timestream, and Kinesis, plus AsyncAPI topic definitions to standardize device data schemas; 2) Static site hosting: S3 + CloudFront with OAI-to-OAC access-control migration and CloudFront ARN exposure for integration; 3) Databricks Managed Workspace (MWS): Terraform-based provisioning (VPC, S3 root storage, and workspace) to enable end-to-end deployment; 4) CI/CD security: AWS OIDC provider and deployment role for GitHub Actions with provider docs; 5) Foundations: OpenTofu baseline for AWS resources with state management (S3 locking) and accompanying infrastructure docs. Impact: faster, secure deployments; improved data routing and schema consistency; reduced operational toil and improved auditability and governance.
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