[gantt-dependencies] GANTT Charts

[Eifi1]

Description

A typical project management chart showing the timeline of a project with specific tasks. Take this as definition:
a chart in which a series of horizontal lines shows the amount of work done or production completed in certain periods of time in relation to the amount planned for those periods.

Applications

Have granularity of each task. Showing the extend of tasks. Showing dependencies of tasks, that one can start only when another task is finished. Combine task groups and show timeline of a task group as well

Data

x data shows the date
y data shows the different tasks

Notes

No response

[claude]

⚠️ Similar Spec Exists

An existing gantt-basic spec covers standard Gantt charts with tasks, dates, and optional category color coding.

Key differences in this request:

• Task dependencies (arrows/connectors showing one task must complete before another starts)
• Task groups/phases with aggregate timelines

Since dependencies and grouping are significant features beyond basic Gantt functionality, I'll create a new spec: gantt-dependencies.

Add label approved to begin generation.

[github-actions]

✅ Specification Ready: gantt-dependencies

PR: #3831

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specification.md

gantt-dependencies: Gantt Chart with Dependencies

Description

A Gantt chart that visualizes project schedules with task dependencies and groupings. Beyond displaying task timelines, this chart shows relationships between tasks using connector arrows, indicating which tasks must complete before others can begin. Tasks can be organized into groups (phases or work packages) with aggregate timeline bars showing the span of each group. This visualization is essential for understanding critical paths and scheduling constraints in complex projects.

Applications

• Project management to visualize task sequences and identify critical path dependencies
• Software development sprint planning showing feature dependencies and blockers
• Construction project scheduling where certain phases must complete before others begin
• Manufacturing workflow planning to coordinate sequential and parallel operations

Data

• task (str) - Name or description of the task
• start (datetime) - Start date/time of the task
• end (datetime) - End date/time of the task
• group (str, optional) - Parent group or phase for hierarchical organization
• depends_on (list[str], optional) - List of task names that must complete before this task starts
• Size: 10-50 tasks for optimal readability with dependencies
• Example: Software project with phases like "Requirements", "Design", "Development", "Testing" where each phase contains multiple dependent tasks

Notes

• Draw dependency arrows/connectors from the end of predecessor tasks to the start of successor tasks
• Use different visual styles for dependency types (finish-to-start is most common)
• Group headers should show aggregate timeline spanning from earliest to latest task in the group
• Consider indentation or color coding to distinguish groups from individual tasks
• Arrows should avoid overlapping task bars where possible
• Include a legend explaining dependency line styles if multiple types are used
• Vertical alignment should clearly show task hierarchy (groups above their child tasks)

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Next: Add approved label to merge this specification to main.

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🤖 spec-create workflow

[github-actions]

🚀 Specification Merged!

Specification: gantt-dependencies
PR: #3831 (merged)

The specification is now in main and synced to PostgreSQL.

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Next: Add generate:{library} labels to start generating implementations.

Available libraries: matplotlib, seaborn, plotly, bokeh, altair, plotnine, pygal, highcharts, letsplot

Or use workflow dispatch for bulk operations.

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🤖 spec-create workflow