plandr

Plandr is a planning and scheduling framework and data format intended to model plans, tasks, resources, and constraints in a vendor-neutral way. It provides a unified schema and execution model designed for interoperability among planning tools, analysis engines, and execution systems.

Origins and development: The project emerged from open-source communities in the early 2020s to address fragmentation in planning data formats. The core specification is published as an open standard under a permissive license, with reference implementations in multiple languages. Governance is community-led, with contributions from software developers, operations researchers, and domain experts.

Data model and features: The plandr model centers on Plan, Task, Milestone, Resource, and Constraint entities. Tasks can have durations, start/end dates, and dependencies; resources can be allocated and have capacities; constraints express deadlines and resource restrictions. Plans can be scheduled, simulated, and exported to JSON or YAML, with APIs for reading and modifying plans. The model supports calendars, soft and hard constraints, and scenario analysis.

Usage and applications: Plandr is used for software project management, event planning, manufacturing scheduling, and urban planning research. It aims to support what-if analysis and automatic plan generation, while enabling exchange between tools via a neutral data format.

Reception and outlook: The initiative has been praised for promoting interoperability and reproducibility but faces challenges in tooling maturity and learning curve. Adoption varies by domain, with some teams preferring established proprietary formats. Ongoing work focuses on expanding libraries, test suites, and integration with optimization engines. See also project management software, data interchange formats.