diff --git a/src/common/ecs/compiler.ts b/src/common/ecs/compiler.ts
index 5b35a017..49761fc9 100644
--- a/src/common/ecs/compiler.ts
+++ b/src/common/ecs/compiler.ts
@@ -183,7 +183,13 @@ export class ECSCompiler extends Tokenizer {
     }
 
     parseCode(): string {
-        return this.expectTokenTypes([TokenType.CodeFragment]).str;
+        let tok = this.expectTokenTypes([TokenType.CodeFragment]);
+        let code = tok.str;
+        let lines = code.split('\n');
+        for (let i=0; i<lines.length; i++) {
+            lines[i] = ` .dbg line, "${this.path}", ${tok.$loc.line+i}\n` + lines[i];
+        }
+        return lines.join('\n');
     }
     
     parseScope() : EntityScope {
@@ -263,6 +269,7 @@ export class ECSCompiler extends Tokenizer {
 
     export() {
         let src = new SourceFileExport();
+        src.debug_file(this.path);
         this.exportToFile(src);
         return src.toString();
     }
diff --git a/src/common/ecs/ecs.ts b/src/common/ecs/ecs.ts
index b8ebf165..a441d32c 100644
--- a/src/common/ecs/ecs.ts
+++ b/src/common/ecs/ecs.ts
@@ -220,6 +220,12 @@ export class SourceFileExport {
         for (let l of s.split('\n'))
             this.lines.push(l);
     }
+    debug_file(path: string) {
+        this.lines.push(` .dbg file, "${path}", 0, 0`);
+    }
+    debug_line(path: string, line: number) {
+        this.lines.push(` .dbg line, "${path}", ${line}`);
+    }
     toString() {
         return this.lines.join('\n');
     }
diff --git a/src/common/tokenizer.ts b/src/common/tokenizer.ts
index 91114f71..07c6e809 100644
--- a/src/common/tokenizer.ts
+++ b/src/common/tokenizer.ts
@@ -71,6 +71,7 @@ export class Tokenizer {
     includeEOL = false;
     errorOnCatchAll = false;
     codeFragment : string | null = null;
+    codeFragmentStart : SourceLocation | null = null;
 
     constructor() {
         this.lineno = 0;
@@ -110,9 +111,13 @@ export class Tokenizer {
                     switch (rule.type) {
                         case TokenType.CodeFragment:
                             if (this.codeFragment) {
-                                this._pushToken({ str: this.codeFragment, type: rule.type, $loc: loc }); //TODO: merge start/end
+                                let codeLoc = mergeLocs(this.codeFragmentStart, loc);
+                                this._pushToken({ str: this.codeFragment, type: rule.type, $loc: codeLoc }); //TODO: merge start/end
+                                this.codeFragmentStart = null;
                                 this.codeFragment = null;
                             } else {
+                                loc.line++;
+                                this.codeFragmentStart = loc;
                                 this.codeFragment = '';
                                 return; // don't add any more tokens (TODO: check for trash?)
                             }