File Format (.dplan)

A .dplan file is a plain UTF-8 JSON file with the .dplan extension. It contains the complete state of one or more projects — tasks, resources, scheduling settings, baseline, holidays, and events. It is human-readable, version-control friendly, and portable across any device with a modern browser.

Saving and Opening

Save: EXPORT ribbon → Save, or Ctrl+S. The browser downloads the file with a filename derived from the project name (spaces → hyphens, e.g., Website-Redesign.dplan).
Open: EXPORT ribbon → Open File, or Ctrl+O. A file picker opens. After selecting the file, DPlan asks Merge or Replace:
- Replace — Discards in-memory state entirely and loads the file. Any unsaved changes are lost. A warning appears if there are unsaved changes.
- Merge — Appends the projects from the file to the current session without removing existing projects. Use for building portfolio views from multiple files.

Replace discards all unsaved in-memory work immediately. Always save your current state (Ctrl+S) before opening a different file with Replace.

Top-Level File Structure

{
  "version": "1.0",
  "exportedAt": "2025-03-15T14:32:00Z",
  "projects": [ ... ]
}

Field	Type	Description
`version`	String	File format version. DPlan uses this to detect files from older versions and apply migrations if needed.
`exportedAt`	ISO 8601 string	UTC timestamp of when the file was saved. Informational only.
`projects`	Array	One or more project objects. Most users have a single project per file, but Portfolio saves embed multiple projects.

Project Object Schema

{
  "id": "proj_a1b2c3",
  "name": "Website Redesign",
  "status": "active",
  "currency": "£",
  "createdAt": "2025-01-10T09:00:00Z",
  "tasks": [ ... ],
  "resources": [ ... ],
  "holidays": [ ... ],
  "events": [ ... ],
  "baseline": { ... } | null,
  "settings": { ... }
}

Field	Type	Description
`id`	String	Unique identifier for this project. Generated on creation, never changes. Prevents ID collisions when merging files.
`name`	String	Display name. Used as filename stem on export.
`status`	String	One of `planning`, `active`, `on-hold`, `completed`.
`currency`	String	Currency symbol for cost display (e.g., `£`, `$`, `€`). Display only — no conversion.
`createdAt`	ISO 8601	Project creation timestamp.
`tasks`	Array	Ordered array of task objects. Order matches display order in the task table. Hierarchy is encoded via the `indent` field, not nesting.
`resources`	Array	Resource pool for this project.
`holidays`	Array	Non-working day definitions.
`events`	Array	Team event definitions.
`baseline`	Object or null	Baseline snapshot, or null if no baseline has been captured.
`settings`	Object	Project-level settings (see below).

Task Object Schema

{
  "id": "task_x9y8z7",
  "name": "Design wireframes",
  "type": "task",
  "indent": 1,
  "start": "2025-03-10",
  "finish": "2025-03-14",
  "duration": 5,
  "progress": 60,
  "status": "in-progress",
  "priority": "high",
  "fixedCost": 0,
  "constraint": "asap",
  "constraintDate": null,
  "anchored": false,
  "resources": ["res_r1s2t3"],
  "dependencies": [
    { "predecessorId": "task_a1b2c3", "lag": 0 }
  ],
  "barColor": null,
  "deadline": null,
  "notes": "Acceptance criteria: responsive at 320px, 768px, 1440px.",
  "collapsed": false,
  "recurrence": null
}

Field	Type	Description
`id`	String	Unique task identifier. Referenced in dependency `predecessorId` fields and resource assignment arrays.
`name`	String	Task display name.
`type`	String	`task`, `milestone`, or `summary`.
`indent`	Integer	Hierarchy depth. 0 = top-level. 1 = child of the nearest parent at depth 0. Used to reconstruct the WBS tree on load — no actual JSON nesting.
`start`	YYYY-MM-DD	Task start date.
`finish`	YYYY-MM-DD	Task finish date.
`duration`	Integer	Duration in working days. Derived field — computed from start/finish on load, but stored for performance.
`progress`	Integer (0–100)	Completion percentage.
`status`	String	`not-started`, `in-progress`, `completed`, `on-hold`, `cancelled`.
`priority`	String	`low`, `medium`, `high`, `critical`.
`fixedCost`	Number	One-time fixed cost in project currency. 0 if none.
`constraint`	String	`asap`, `alap`, `snet`, `snlt`, `fnet`, `mso`.
`constraintDate`	YYYY-MM-DD or null	Date for SNET/SNLT/FNET/MSO constraints. Null for ASAP/ALAP.
`anchored`	Boolean	If true, auto-scheduler will not move this task's start date.
`resources`	Array of IDs	Resource IDs from the project's resource pool assigned to this task.
`dependencies`	Array of objects	Each object: `{ predecessorId, lag }`. `lag` is in working days — positive = delay, negative = overlap (lead).
`barColor`	CSS color string or null	Custom bar color override. Null = use theme default.
`deadline`	YYYY-MM-DD or null	Advisory deadline. Warning shown if finish exceeds this date.
`notes`	String	Free-form notes. Empty string if none.
`collapsed`	Boolean	For summary tasks: whether children are hidden in the view. Preserved on save.
`recurrence`	Object or null	Recurrence rule object for recurring tasks. See Recurring Tasks. Null for non-recurring tasks.

Resource Object Schema

{
  "id": "res_r1s2t3",
  "name": "Alice Chen",
  "role": "Frontend Developer",
  "dayRate": 450
}

Field	Type	Description
`id`	String	Unique resource identifier. Referenced in task `resources` arrays.
`name`	String	Display name. Shown in task bars, table, and exports.
`role`	String	Job title or role description. Informational, shown in Excel Resources sheet.
`dayRate`	Number	Cost per working day. Used in cost calculations when Cost Tracking is enabled.

Holiday and Event Schemas

// Holiday
{ "date": "2025-12-25", "name": "Christmas Day" }

// Event
{ "id": "evt_e1f2g3", "date": "2025-03-01", "name": "Sprint 5 Demo", "color": "#9c59d1" }

Holidays are simple date + name pairs. Events additionally carry an ID and a color for rendering on the Gantt and Calendar.

Baseline Object

{
  "capturedAt": "2025-02-01T08:00:00Z",
  "tasks": [
    { "id": "task_x9y8z7", "start": "2025-03-10", "finish": "2025-03-14" },
    ...
  ]
}

The baseline stores the snapshot start and finish dates for every task at the time SCHEDULE → Set Baseline was triggered. On load, DPlan compares current task dates against baseline dates to render variance bars. See Baseline.

Settings Object

{
  "progressRollup": true,
  "costTracking": false,
  "baselineVarianceBars": false,
  "notesHoverPreview": true,
  "dragDropReorder": true
}

These are the five feature toggles from the Settings panel, saved per-project. Note that theme is not stored here — it is a device-level preference stored separately in localStorage and never written to the .dplan file.

Auto-Save to localStorage

DPlan automatically saves the current in-memory project state to localStorage after every meaningful change: adding/editing/deleting a task, changing dates, updating progress, etc. This provides session recovery if the browser closes unexpectedly. On next open, DPlan restores the last auto-saved state.

localStorage limits vary by browser but are typically 5–10 MB per origin. A project with hundreds of tasks and detailed notes may approach this limit. DPlan does not currently warn when approaching the limit — save a .dplan file regularly to ensure you have a recoverable backup outside the browser.

Clearing browser data, browsing history, or site data will erase localStorage, losing any unsaved work. The .dplan file is the only reliable long-term backup. Export it at the end of every session.

Portability and Forward Compatibility

Any modern browser — Chrome, Firefox, Safari, Edge. No plugins, no installation.
Cloud drives — Store .dplan files in Google Drive, Dropbox, or OneDrive and open them on any device.
Version control — Commit .dplan files to Git. Diffs are human-readable JSON field changes.
Forward compatibility — Future DPlan versions will read current .dplan files. Unknown fields are preserved and ignored, so third-party tools can safely annotate .dplan files with extra fields.
Manual editing — Because the format is plain JSON, you can edit a .dplan file in any text editor for bulk changes (e.g., shifting all dates, bulk status updates) using find-and-replace or a script.