diff --git a/lib/evinser/evinser.js b/lib/evinser/evinser.js
index f3279a3f6..2177e8e65 100644
--- a/lib/evinser/evinser.js
+++ b/lib/evinser/evinser.js
@@ -212,7 +212,7 @@ export async function createSlice(
   options = {},
 ) {
   if (!filePath) {
-    return;
+    return undefined;
   }
   const firstLanguage = Array.isArray(purlOrLanguages)
     ? purlOrLanguages[0]
@@ -227,7 +227,7 @@ export async function createSlice(
     PROJECT_TYPE_ALIASES.swift.includes(language) &&
     sliceType !== "semantics"
   ) {
-    return;
+    return undefined;
   }
 
   let sliceOutputDir = fs.mkdtempSync(
@@ -388,7 +388,7 @@ export async function analyzeProject(dbObjMap, options) {
         fs.readFileSync(options.reachablesSlicesFile, "utf-8"),
       );
     } else {
-      retMap = createSlice(language, dirPath, "reachables", options);
+      retMap = await createSlice(language, dirPath, "reachables", options);
       if (retMap?.slicesFile && fs.existsSync(retMap.slicesFile)) {
         reachablesSlicesFile = retMap.slicesFile;
         reachablesSlice = JSON.parse(
@@ -409,7 +409,7 @@ export async function analyzeProject(dbObjMap, options) {
     usagesSlicesFile = options.usagesSlicesFile;
   } else {
     // Generate our own slices
-    retMap = createSlice(language, dirPath, "usages", options);
+    retMap = await createSlice(language, dirPath, "usages", options);
     if (retMap?.slicesFile && fs.existsSync(retMap.slicesFile)) {
       usageSlice = JSON.parse(fs.readFileSync(retMap.slicesFile, "utf-8"));
       usagesSlicesFile = retMap.slicesFile;
@@ -428,7 +428,7 @@ export async function analyzeProject(dbObjMap, options) {
       semanticsSlicesFile = options.semanticsSlicesFile;
     } else {
       // Generate our own slices
-      retMap = createSlice(language, dirPath, "semantics", options);
+      retMap = await createSlice(language, dirPath, "semantics", options);
       if (retMap?.slicesFile && fs.existsSync(retMap.slicesFile)) {
         semanticsSlice = JSON.parse(
           fs.readFileSync(retMap.slicesFile, "utf-8"),
@@ -471,7 +471,7 @@ export async function analyzeProject(dbObjMap, options) {
         fs.readFileSync(options.dataFlowSlicesFile, "utf-8"),
       );
     } else {
-      retMap = createSlice(language, dirPath, "data-flow", options);
+      retMap = await createSlice(language, dirPath, "data-flow", options);
       if (retMap?.slicesFile && fs.existsSync(retMap.slicesFile)) {
         dataFlowSlicesFile = retMap.slicesFile;
         dataFlowSlice = JSON.parse(fs.readFileSync(retMap.slicesFile, "utf-8"));