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DRC Import

Select a manufacturer preset or import custom PCB rules, then inspect the active rules and DRC findings.

What It Does

A compatible .kicad_dru file adds custom PCB constraints to the active project. Manufacturer presets provide a starting point for an encoded process; they do not cover every manufacturing requirement.

Open a saved board and keep a copy of its existing custom rules before importing or changing presets. See build and host availability for native controls and companion differences.

How to Import

From the Desktop App

  1. Open Inspect → Design Rules Checker in the native Full interface.
  2. Beside Rules Preset, choose Import….
  3. Select the intended .kicad_dru file and name its manufacturer/source when prompted.
  4. Read the import log. Confirm that the file parsed and the intended custom rules loaded. The imported preset is labelled Custom: source, using the manufacturer/source name you entered.
  5. Inspect the rule values and conditions, refill zones, and click Run DRC.
  6. Review and resolve findings against the actual process requirements.

Import replaces the project's active custom-rule file. A copied file can still fail to parse; do not treat “copied” as successful rule activation.

From the DRC Rule Editor

Use Tools → DRC Rule Editor to inspect or edit the resulting constraints in the native Full interface. The import procedure above uses the Design Rules Checker; do not look for an assumed drag-and-drop or Import Rules control in every editor.

From the CLI

Use trace-cli from the Trace app after signing in to the desktop. Check its reference and installed help for supported rule operations; a desktop dialog does not imply an equivalent command.

What Gets Imported

Compatible files can define constraints such as clearance, track width, hole size, annular width, edge clearance, courtyard spacing, and text dimensions with conditional expressions. Check the installed rule grammar; a capability table does not automatically become a supported constraint.

Impedance, drill aspect ratio, special stackups, and assembly processes can require separate configuration or manufacturer review.

How Constraints Flow Into TraceRules

A successful native import can add a manufacturer/constraint summary to .trace/rules.md for assistant context. That note is not the DRC engine's rule file and does not continuously validate every edit. Check the active .kicad_dru and rerun DRC.

Manufacturer Presets

Select the preferred manufacturer on the native PCB toolbar, then check Rules Preset in DRC. Compatible builds apply that manufacturer's preset; PCBWay selection depends on layer count and copper weight, while Pikkolo uses its available standard preset.

Default (no manufacturer) returns to baseline board/net-class rules and removes the active manufacturer custom-rule preset. It is not a claim that there are no rules. Save custom rules first if you need to keep them.

Imported rules use Custom: source immediately after import; other custom-rule states can show Custom (project rules). Neither label establishes a stock-preset match or manufacturer approval. Verify current manufacturer capabilities instead of relying on a copied preset name.

Workflow: Import → Design → Validate

Select or import the intended rules, inspect their scope, design against those requirements, and rerun DRC after relevant edits and before export. Approve specific corrections separately; neither a preset nor a general “fix everything” request establishes the right engineering change.

Overriding Imported Rules

Change the actual board/custom rules only with an explicit engineering rationale and any required written manufacturer approval. A prose override in .trace/rules.md does not take precedence over DRC or establish that the fab accepts an exception.

Creating a .kicad_dru for Your Manufacturer

Use the DRC Rule Editor or compatible custom-rule syntax to encode confirmed requirements. This illustrative file is syntax guidance, not a manufacturer's approved process:

(version 1)

(rule "Minimum Clearance"
  (constraint clearance (min 0.2mm))
)

(rule "Minimum Track Width"
  (constraint track_width (min 0.2mm))
)

Substitute justified limits, import into a copy of the project, check parsing, and inspect DRC findings.

Review Findings Before Excluding Them

Do not suppress a category merely to obtain an empty report. Evaluate individual findings, distinguish intentional no-connects from missing connections, and use explicit native exclusions only with a documented reason. Assistant prose is not a DRC exclusion.

If Import Fails

If the log reports a copy or parse failure, inspect the active file and restore the previous rules if necessary. Correct unsupported syntax or file-access problems before rerunning DRC. Do not proceed as though baseline or imported rules were successfully checked.