diff --git a/src/meson.build b/src/meson.build
index 172c191dbffe4f84f9a7c3acb19e6b67b873569d..6cb6090763f7ad6af6b4ec0c7f1226633279501f 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -28,7 +28,7 @@ sources = files(
   'warning.ts',
   'window.ts',
 )
-
+tsc_in = meson.project_source_root()
 tsc_out = meson.project_build_root() / 'tsc-out'
 
 typescript = custom_target(
@@ -36,7 +36,7 @@ typescript = custom_target(
   input: sources,
   build_by_default: true,
   build_always_stale: true,
-  command: [ tsc, '--outDir', tsc_out ],
+  command: [ tsc, '-p', tsc_in, '--outDir', tsc_out ],
   output: ['tsc-output'],
 )