--- afdko/c/mergefonts/mergeFonts.cpp
+++ afdko/c/mergefonts/mergeFonts.cpp
@@ -1384,3 +1384,50 @@
 
     return 0;
 }
+
+/* Embedding interface: the same wiring as main__mergefonts above, but with
+   heap allocation and caller-driven steps in place of argv parsing. */
+extern "C" txCtx mergeFontsNew(void) {
+    MergeInfo *mi = (MergeInfo *)calloc(1, sizeof(MergeInfo));
+    txExtCtx e = (txExtCtx)calloc(1, sizeof(struct txExtCtx_));
+    txCtx h = (txCtx)calloc(1, sizeof(struct txCtx_));
+
+    if (mi == NULL || e == NULL || h == NULL) {
+        free(mi);
+        free(e);
+        free(h);
+        return NULL;
+    }
+
+    e->extData = mi;
+    e->progname = "mergefonts";
+    e->version = MERGEFONTS_VERSION;
+    e->processOption = &mf_processOption;
+    e->usage = &mf_usage;
+    e->help = &mf_help;
+    e->cfr_ReadFontCB = &mf_cfr_ReadFontCB;
+
+    mi->tx = h;
+
+    txNew(h, e);
+
+    return h;
+}
+
+extern "C" void mergeFontsFree(txCtx h) {
+    txExtCtx e = h->ext;
+    void *mi = e->extData;
+
+    txFree(h);
+    free(mi);
+    free(e);
+    free(h);
+}
+
+extern "C" void mergeFontsReadCIDFontInfo(txCtx h, const char *filePath) {
+    readCIDFontInfo((MergeInfo *)h->ext->extData, filePath);
+}
+
+extern "C" int mergeFontsDoMergeFileSet(txCtx h, int argc, char *argv[], int i) {
+    return doMergeFileSet(h, argc, argv, i);
+}