Dependencies on a Timeline

Description

Problem

Visualize relations on a timeline view
Manage relations (add, remove)

Solution

TLDR:

We create new Dependency modificator for self-relation (any cardinality), it is stored in Schema.
Timeline VIew only visualize arrows for self-relations with Dependency modificator
A user can see, create, and delete dependencies on timeline view
There are date-shifting strategies that work ONLY on timeline view for given dependency relation and selected Dates.

Dependency relation

It should be possible to mark self-relation as Dependency. On a backend it is just a property in relation field schema.

Timeline View allows to visualize only Dependency relations as arrows. Dependency relation config on field editor

Timeline view Setup

Dependencies are possible only between same-database entities, like Feature-Feature, Epic-Epic, etc. So a user can use a relation marked as Dependency that will serve as dependency.

If no relation exists and a user has no permission to create fields in this database → hide Enable dependencies button

❗️ So far we do not provide Relation field selection for Timeline. In theory we can have more than one Dependency relation field, but in this case we just take the first one and use it when a user enables dependencies.

Screenshot 2025-01-25 at 10.27.54 AM.png

❓ How to define relation direction? In many cases it is m-m, so no clear direction is here. → It is set on relation creation, so when Dependency is marked, a user should also set a direction setting.

When dependencies are enabled, addition options are visible:

Automatic dates shifting (3 choices)
… (more settings can be added later)

Screenshot 2025-01-25 at 10.30.16 AM.png

Timeline View dependencies visualization and changes

Dependencies management on Timeline (show, add, edit, delete)

Many-to-many lanes → show arrows for all cards.
Dependencies are always End-to-Start.

Dates re-calculation

~~We can treat it as UI problem and introduce some limitations~~

We recalculate dates only on Timeline View when a user changes things. Dependencies shifting mode - shift dependencies when dates overlap

It is not a server side solution, so if a user changes dates or relations on other places, re-calculation WILL NOT happen.
We recalculate dates based on selected relation and dates fields.

References

Linear

https://linear.app/docs/project-dependencies

Rules

When dragging a project with dependencies, there are several ergonomics to help you plan quickly:
Any projects in the dependency chain that are backlog or planned will be "bumped" with the dragged project. Hold METAKEY to keep the chain in place.
Hold SHIFTKEY to move all projects in the dependency together, regardless of status.