diff --git a/audacity-cmake/Makefile b/audacity-cmake/Makefile
index 5580cd8016..f7385e6fc0 100644
--- a/audacity-cmake/Makefile
+++ b/audacity-cmake/Makefile
@@ -13,6 +13,8 @@ LICENSE=	gnu-gpl-v2 # AND cc-by-v3.0-license
 
 WRKSRC=		${WRKDIR}/audacity-${GITHUB_PROJECT}-${PKGVERSION_NOREV}
 
+BUILD_DEPENDS+=	nasm-[0-9]*:../../devel/nasm
+
 USE_CMAKE=	yes
 USE_TOOLS+=	pkg-config msgfmt msgmerge
 USE_LANGUAGES=	c c++
@@ -48,6 +50,8 @@ CMAKE_ARGS+=	-Daudacity_use_twolame=system
 CMAKE_ARGS+=	-Daudacity_use_vamp=system
 CMAKE_ARGS+=	-Daudacity_use_vorbis=system
 CMAKE_ARGS+=	-Daudacity_use_wxwidgets=system
+# pre-compiled headers don't work well on some systems
+CMAKE_ARGS+=	-Daudacity_use_pch=no
 
 CMAKE_ARGS+=	-DLIB_avcodec=${PREFIX}/lib/ffmpeg4/libavcodec.so
 CMAKE_ARGS+=	-DLIB_avformat=${PREFIX}/lib/ffmpeg4/libavformat.so
@@ -78,7 +82,7 @@ CXXFLAGS+=		-march=i586
 
 CFLAGS.SunOS+=		-fPIC
 
-PYTHON_VERSIONS_ACCEPTED=	27
+PYTHON_VERSIONS_INCOMPATIBLE=	27
 PYTHON_FOR_BUILD_ONLY=		tool
 
 pre-configure:
diff --git a/audacity-cmake/TODO b/audacity-cmake/TODO
index 04e90f5a1f..807be74e7a 100644
--- a/audacity-cmake/TODO
+++ b/audacity-cmake/TODO
@@ -1 +1,5 @@
-Fails to start.
+Fails to compile:
+/scratch/wip/audacity-cmake/work/audacity-Audacity-2.4.2/src/AboutDialog.cpp:66:10: fatal error: RevisionIdent.h: No such file or directory
+ #include <RevisionIdent.h>                                                              
+          ^~~~~~~~~~~~~~~~~
+
diff --git a/audacity-cmake/distinfo b/audacity-cmake/distinfo
index 28b0cfd1f9..8077c5ed08 100644
--- a/audacity-cmake/distinfo
+++ b/audacity-cmake/distinfo
@@ -12,6 +12,7 @@ SHA1 (patch-cmake-proxies_portmidi_CMakeLists.txt) = 661dd5714908299fea9b8612a76
 SHA1 (patch-lib-src_header-substitutes_allegro.h) = e25aa6f348eb52f500099ce829347b7601ba13be
 SHA1 (patch-lib-src_libnyquist_nyquist_cmupv_src_cmupv.c) = 3d6cb845d82b1bcbe31dabd4bad30cb1f7ea27d5
 SHA1 (patch-lib-src_libnyquist_nyquist_sys_unix_switches.h) = d313f137f11d3e0fafa383ddeccbc89021e9ddee
+SHA1 (patch-lib-src_libnyquist_nyquist_xlisp_security.c) = 2712a9b0a89a0154fe6b2c59cbd3ad3654d6c3d2
 SHA1 (patch-lib-src_libnyquist_nyquist_xlisp_xlisp.h) = 2d4558f059d86633a1fcdda22ef0c914758b35a0
 SHA1 (patch-src_AudioIO.cpp) = 1b44c68c4233b24a5fa4e17515eb237fee0e283a
 SHA1 (patch-src_CMakeLists.txt) = 7f88c6433e70b900d401f04871a4591b6c991983
diff --git a/audacity-cmake/patches/patch-lib-src_libnyquist_nyquist_xlisp_security.c b/audacity-cmake/patches/patch-lib-src_libnyquist_nyquist_xlisp_security.c
new file mode 100644
index 0000000000..794af44645
--- /dev/null
+++ b/audacity-cmake/patches/patch-lib-src_libnyquist_nyquist_xlisp_security.c
@@ -0,0 +1,15 @@
+$NetBSD$
+
+unistd is also needed on NetBSD.
+
+--- lib-src/libnyquist/nyquist/xlisp/security.c.orig	2020-06-19 15:16:47.000000000 +0000
++++ lib-src/libnyquist/nyquist/xlisp/security.c
+@@ -4,7 +4,7 @@
+  */
+ 
+ #include <stdlib.h>
+-#if defined(UNIX) || defined(__APPLE__) || defined(__CYGWIN__)
++#if defined(UNIX) || defined(__APPLE__) || defined(__CYGWIN__) || defined(__NetBSD__)
+ #include <unistd.h>
+ #endif
+ #ifdef WIN32