diff --git a/compiler/gengo/gengo.go b/compiler/gengo/gengo.go
index 28e72e8..82025af 100644
--- a/compiler/gengo/gengo.go
+++ b/compiler/gengo/gengo.go
@@ -180,14 +180,29 @@ func doGenerate(file *ast.File, debug, library bool) string {
 	}
 	g.emitSymCache()
 
-	// Patch deferred imports: inline RTL may add "fmt"/"strings" after header was emitted.
+	// Patch deferred imports: emitDecl may add to g.imports after the
+	// header was written. The common cases are inline RTL pulling in
+	// "fmt"/"strings", but #pragma BEGINDUMP blocks can also hoist
+	// third-party / private modules (e.g. solmade's internal/dartapi).
+	// Dump every import not already in the header so external Go
+	// packages used inside BEGINDUMP actually link.
 	result := g.buf.String()
-	var deferred string
-	if g.imports["fmt"] && !strings.Contains(result, "\"fmt\"") {
-		deferred += "\t\"fmt\"\n"
+	var deferredLines []string
+	for imp := range g.imports {
+		if strings.Contains(result, "\""+imp+"\"") {
+			continue // already emitted in the initial import block
+		}
+		if alias, ok := g.importAlias[imp]; ok && alias != "" {
+			deferredLines = append(deferredLines, fmt.Sprintf("\t%s %q", alias, imp))
+		} else {
+			deferredLines = append(deferredLines, fmt.Sprintf("\t%q", imp))
+		}
 	}
-	if g.imports["strings"] && !strings.Contains(result, "\"strings\"") {
-		deferred += "\t\"strings\"\n"
+	// Sorted for deterministic diffs.
+	sort.Strings(deferredLines)
+	deferred := strings.Join(deferredLines, "\n")
+	if deferred != "" {
+		deferred += "\n"
 	}
 	result = strings.Replace(result, "\t/*DEFERRED_IMPORTS*/\n", deferred, 1)
 	// Patch guards