diff --git a/README.md b/README.md
index ac59acc..e594611 100644
--- a/README.md
+++ b/README.md
@@ -116,6 +116,7 @@ Everything will immediately show up in ImHex's Content Store and gets bundled wi
 | QOI  | `image/qoi` | [`patterns/qoi.hexpat`](patterns/qoi.hexpat) | QOI image files |
 | RAS  | `image/x-sun-raster` | [`patterns/ras.hexpat`](patterns/ras.hexpat) | RAS image files |
 | ReFS | | [`patterns/refs.hexpat`](patterns/refs.hexpat) | Microsoft Resilient File System |
+| RGBDS | | [`patterns/rgbds.hexpat`](patterns/rgbds.hexpat) | [RGBDS](https://rgbds.gbdev.io) object file format |
 | Shell Link | `application/x-ms-shortcut` | [`patterns/lnk.hexpat`](patterns/lnk.hexpat) | Windows Shell Link file format |
 | shp | | [`patterns/shp.hexpat`](patterns/shp.hexpat) | ESRI shape file |
 | shx | | [`patterns/shx.hexpat`](patterns/shx.hexpat) | ESRI index file |
diff --git a/patterns/rgbds.hexpat b/patterns/rgbds.hexpat
new file mode 100644
index 0000000..5752824
--- /dev/null
+++ b/patterns/rgbds.hexpat
@@ -0,0 +1,132 @@
+#pragma author ISSOtm <imhex@eldred.fr>
+#pragma description Object files for the RGBDS Game Boy assembly toolchain
+// Documentation: https://rgbds.gbdev.io/docs/rgbds.5
+
+#pragma magic [ 52 47 42 39 ] @ 0x00
+#pragma endian little
+
+#include <std/string>
+
+using LONG = u32;
+using BYTE = u8;
+using STRING = std::string::NullString;
+
+char magic[4] @ 0;
+LONG revNum @ $;
+LONG nbSym @ $;
+LONG nbSect @ $;
+
+namespace fstack {
+    enum Type : BYTE {
+        REPT,
+        File,
+        Macro,
+    };
+    struct Node {
+        LONG parentID;
+        LONG parentLineNo;
+        Type type;
+        if (type != Type::REPT) {
+            STRING name;
+        } else {
+            LONG depth;
+            LONG iters[depth];
+        }
+    };
+        
+    LONG nbNodes @ $;
+    Node nodes[nbNodes] @ $;
+}
+
+namespace sym {
+    enum Type : BYTE {
+        Local,
+        Import,
+        Exported,
+    };
+    struct Symbol {
+        STRING name;
+        Type type;
+        if (type != Type::Import) {
+            LONG nodeID;
+            LONG lineNo;
+            LONG sectionID;
+            LONG value;
+        }
+    };
+    
+    Symbol symbols[nbSym] @ $;
+}
+
+namespace sect {
+    enum PatchType : BYTE {
+        DB,
+        DW,
+        DL,
+        JR,
+    };
+    struct Patch {
+        LONG nodeID;
+        LONG lineNo;
+        LONG ofs;
+        LONG pcSectID;
+        LONG pcOfs;
+        PatchType type;
+        LONG rpnSize;
+        BYTE rpn[rpnSize];
+    };
+    
+    enum Type : BYTE {
+        WRAM0,
+        VRAM,
+        ROMX,
+        ROM0,
+        HRAM,
+        WRAMX,
+        SRAM,
+        OAM,
+    };
+    bitfield Attrs {
+        Type type       : 6;
+        bool isFragment : 1;
+        bool isUnion    : 1;
+    };
+    struct Section {
+        STRING name;
+        LONG size;
+        Attrs attrs;
+        LONG address;
+        LONG bank;
+        BYTE alignment;
+        LONG alignOfs;
+        if (attrs.type == Type::ROMX || attrs.type == Type::ROM0) {
+            BYTE data[size];
+            LONG nbPatches;
+            Patch patches[nbPatches];
+        }
+    };
+    
+    Section sections[nbSect] @ $;
+}
+
+namespace assert {
+    enum Type : BYTE {
+        Warn,
+        Err,
+        Fatal,
+    };
+    struct Assertion {
+        LONG nodeID;
+        LONG lineNo;
+        LONG ofs;
+        LONG pcSectID;
+        LONG pcOfs;
+        Type type;
+        LONG rpnSize;
+        BYTE rpn[rpnSize];
+        STRING msg;
+    };
+    
+    LONG nbAsserts @ $;
+    Assertion assertions[nbAsserts] @ $;
+}
diff --git a/tests/patterns/test_data/rgbds.hexpat.o b/tests/patterns/test_data/rgbds.hexpat.o
new file mode 100644
index 0000000..5a067b5
Binary files /dev/null and b/tests/patterns/test_data/rgbds.hexpat.o differ