diff --git a/src/compiler/tsbuildPublic.ts b/src/compiler/tsbuildPublic.ts
index 8ba95effdf738..a6f71ec4d4b18 100644
--- a/src/compiler/tsbuildPublic.ts
+++ b/src/compiler/tsbuildPublic.ts
@@ -874,8 +874,10 @@ namespace ts {
             if (state.watch) {
                 state.lastCachedPackageJsonLookups.set(projectPath, state.moduleResolutionCache && map(
                     state.moduleResolutionCache.getPackageJsonInfoCache().entries(),
-                    ([path, data]) => ([state.host.realpath ? toPath(state, state.host.realpath(path)) : path, data] as const)
+                    ([path, data]) => ([state.host.realpath && data ? toPath(state, state.host.realpath(path)) : path, data] as const)
                 ));
+
+                state.builderPrograms.set(projectPath, program);
             }
             step++;
         }