diff --git a/.gitignore b/.gitignore
index 724a8b8..e2b3647 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,6 +13,10 @@ _autosave-*
 *-save.pro
 *-save.kicad_pcb
 fp-info-cache
+# KiCad auto-backup folders
+*-backups/
+# KiCad local project settings (doesn't contain design info)
+*.kicad_prl
 
 # Netlist files (exported from Eeschema)
 *.net
@@ -25,3 +29,6 @@ fp-info-cache
 *.xml
 *.FCStd1
 out/
+
+# Freecad backups
+*.FCBak
diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-26_135615.zip b/pcb/interposer/interposer-backups/interposer-2025-06-26_135615.zip
deleted file mode 100644
index 58012b7..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-26_140259.zip b/pcb/interposer/interposer-backups/interposer-2025-06-26_140259.zip
deleted file mode 100644
index fd515ad..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-26_140822.zip b/pcb/interposer/interposer-backups/interposer-2025-06-26_140822.zip
deleted file mode 100644
index b0f0c49..0000000
Binary files a/pcb/interposer/interposer-backups/interposer-2025-06-26_140822.zip and /dev/null differ
diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-26_142145.zip b/pcb/interposer/interposer-backups/interposer-2025-06-26_142145.zip
deleted file mode 100644
index bb9a907..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-26_145817.zip b/pcb/interposer/interposer-backups/interposer-2025-06-26_145817.zip
deleted file mode 100644
index ce413e8..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-27_155815.zip b/pcb/interposer/interposer-backups/interposer-2025-06-27_155815.zip
deleted file mode 100644
index 64f9a79..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-27_162026.zip b/pcb/interposer/interposer-backups/interposer-2025-06-27_162026.zip
deleted file mode 100644
index 27004dd..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-27_164959.zip b/pcb/interposer/interposer-backups/interposer-2025-06-27_164959.zip
deleted file mode 100644
index cd74d0b..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-29_224654.zip b/pcb/interposer/interposer-backups/interposer-2025-06-29_224654.zip
deleted file mode 100644
index b89caf6..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-30_113959.zip b/pcb/interposer/interposer-backups/interposer-2025-06-30_113959.zip
deleted file mode 100644
index 275384e..0000000
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diff --git a/pcb/interposer/interposer-backups/interposer-2025-06-30_114525.zip b/pcb/interposer/interposer-backups/interposer-2025-06-30_114525.zip
deleted file mode 100644
index e5d0218..0000000
Binary files a/pcb/interposer/interposer-backups/interposer-2025-06-30_114525.zip and /dev/null differ
diff --git a/pcb/interposer/interposer-backups/interposer-2025-07-01_103520.zip b/pcb/interposer/interposer-backups/interposer-2025-07-01_103520.zip
deleted file mode 100644
index ffd980b..0000000
Binary files a/pcb/interposer/interposer-backups/interposer-2025-07-01_103520.zip and /dev/null differ
diff --git a/pcb/interposer/interposer-backups/interposer-2025-07-01_104159.zip b/pcb/interposer/interposer-backups/interposer-2025-07-01_104159.zip
deleted file mode 100644
index 3627d15..0000000
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diff --git a/pcb/interposer/interposer.kicad_prl b/pcb/interposer/interposer.kicad_prl
deleted file mode 100644
index f0b7e17..0000000
--- a/pcb/interposer/interposer.kicad_prl
+++ /dev/null
@@ -1,130 +0,0 @@
-{
-  "board": {
-    "active_layer": 25,
-    "active_layer_preset": "All Layers",
-    "auto_track_width": true,
-    "hidden_netclasses": [],
-    "hidden_nets": [],
-    "high_contrast_mode": 0,
-    "net_color_mode": 1,
-    "opacity": {
-      "images": 0.6,
-      "pads": 1.0,
-      "shapes": 1.0,
-      "tracks": 1.0,
-      "vias": 1.0,
-      "zones": 0.6
-    },
-    "selection_filter": {
-      "dimensions": true,
-      "footprints": true,
-      "graphics": true,
-      "keepouts": true,
-      "lockedItems": false,
-      "otherItems": true,
-      "pads": true,
-      "text": true,
-      "tracks": true,
-      "vias": true,
-      "zones": true
-    },
-    "visible_items": [
-      "vias",
-      "footprint_text",
-      "footprint_anchors",
-      "ratsnest",
-      "grid",
-      "footprints_front",
-      "footprints_back",
-      "footprint_values",
-      "footprint_references",
-      "tracks",
-      "drc_errors",
-      "drawing_sheet",
-      "bitmaps",
-      "pads",
-      "zones",
-      "drc_warnings",
-      "locked_item_shadows",
-      "conflict_shadows",
-      "shapes"
-    ],
-    "visible_layers": "ffffffff_ffffffff_ffffffff_ffffffff",
-    "zone_display_mode": 0
-  },
-  "git": {
-    "repo_type": "",
-    "repo_username": "",
-    "ssh_key": ""
-  },
-  "meta": {
-    "filename": "interposer.kicad_prl",
-    "version": 5
-  },
-  "net_inspector_panel": {
-    "col_hidden": [
-      false,
-      false,
-      false,
-      false,
-      false,
-      false,
-      false,
-      false,
-      false,
-      false
-    ],
-    "col_order": [
-      0,
-      1,
-      2,
-      3,
-      4,
-      5,
-      6,
-      7,
-      8,
-      9
-    ],
-    "col_widths": [
-      156,
-      141,
-      103,
-      71,
-      103,
-      103,
-      103,
-      74,
-      103,
-      103
-    ],
-    "custom_group_rules": [],
-    "expanded_rows": [],
-    "filter_by_net_name": true,
-    "filter_by_netclass": true,
-    "filter_text": "",
-    "group_by_constraint": false,
-    "group_by_netclass": false,
-    "show_unconnected_nets": false,
-    "show_zero_pad_nets": false,
-    "sort_ascending": true,
-    "sorting_column": 0
-  },
-  "open_jobsets": [],
-  "project": {
-    "files": []
-  },
-  "schematic": {
-    "selection_filter": {
-      "graphics": true,
-      "images": true,
-      "labels": true,
-      "lockedItems": false,
-      "otherItems": true,
-      "pins": true,
-      "symbols": true,
-      "text": true,
-      "wires": true
-    }
-  }
-}
diff --git a/pcb/light-diffusion/light-diffusion.kicad_prl b/pcb/light-diffusion/light-diffusion.kicad_prl
deleted file mode 100644
index 84e574c..0000000
--- a/pcb/light-diffusion/light-diffusion.kicad_prl
+++ /dev/null
@@ -1,77 +0,0 @@
-{
-  "board": {
-    "active_layer": 44,
-    "active_layer_preset": "All Layers",
-    "auto_track_width": true,
-    "hidden_netclasses": [],
-    "hidden_nets": [],
-    "high_contrast_mode": 0,
-    "net_color_mode": 1,
-    "opacity": {
-      "images": 0.6,
-      "pads": 1.0,
-      "tracks": 1.0,
-      "vias": 1.0,
-      "zones": 0.6
-    },
-    "ratsnest_display_mode": 0,
-    "selection_filter": {
-      "dimensions": true,
-      "footprints": true,
-      "graphics": true,
-      "keepouts": true,
-      "lockedItems": true,
-      "otherItems": true,
-      "pads": true,
-      "text": true,
-      "tracks": true,
-      "vias": true,
-      "zones": true
-    },
-    "visible_items": [
-      0,
-      1,
-      2,
-      3,
-      4,
-      5,
-      8,
-      9,
-      10,
-      12,
-      13,
-      15,
-      16,
-      17,
-      18,
-      19,
-      20,
-      21,
-      22,
-      23,
-      24,
-      25,
-      26,
-      27,
-      28,
-      29,
-      30,
-      32,
-      33,
-      34,
-      35,
-      36,
-      39,
-      40
-    ],
-    "visible_layers": "fffffff_ffffffff",
-    "zone_display_mode": 0
-  },
-  "meta": {
-    "filename": "light-diffusion.kicad_prl",
-    "version": 3
-  },
-  "project": {
-    "files": []
-  }
-}
diff --git a/pcb/photon-8mm-fid/fiducialBoard.kicad_prl b/pcb/photon-8mm-fid/fiducialBoard.kicad_prl
deleted file mode 100644
index 99b3d52..0000000
--- a/pcb/photon-8mm-fid/fiducialBoard.kicad_prl
+++ /dev/null
@@ -1,77 +0,0 @@
-{
-  "board": {
-    "active_layer": 0,
-    "active_layer_preset": "",
-    "auto_track_width": true,
-    "hidden_netclasses": [],
-    "hidden_nets": [],
-    "high_contrast_mode": 0,
-    "net_color_mode": 1,
-    "opacity": {
-      "images": 0.6,
-      "pads": 1.0,
-      "tracks": 1.0,
-      "vias": 1.0,
-      "zones": 0.6
-    },
-    "ratsnest_display_mode": 0,
-    "selection_filter": {
-      "dimensions": true,
-      "footprints": true,
-      "graphics": true,
-      "keepouts": true,
-      "lockedItems": true,
-      "otherItems": true,
-      "pads": true,
-      "text": true,
-      "tracks": true,
-      "vias": true,
-      "zones": true
-    },
-    "visible_items": [
-      0,
-      1,
-      2,
-      3,
-      4,
-      5,
-      8,
-      9,
-      10,
-      11,
-      12,
-      13,
-      14,
-      15,
-      16,
-      17,
-      18,
-      19,
-      20,
-      21,
-      22,
-      23,
-      24,
-      25,
-      26,
-      27,
-      28,
-      29,
-      30,
-      32,
-      33,
-      34,
-      35,
-      36
-    ],
-    "visible_layers": "7ffffff_80000001",
-    "zone_display_mode": 0
-  },
-  "meta": {
-    "filename": "fiducialBoard.kicad_prl",
-    "version": 3
-  },
-  "project": {
-    "files": []
-  }
-}