diff --git a/.gitignore b/.gitignore
index 56e074416..bc76a3aa3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,9 @@ ehthumbs_vista.db
 ._*
 programs/cmm/cmm.code-workspace
 programs/cmm/menu/.gitignore
+
+.tup/
+
+/build-*/
+/*.config
+
diff --git a/contrib/sdk/sources/sound/Tupfile.lua b/contrib/sdk/sources/sound/Tupfile.lua
new file mode 100644
index 000000000..f3f542cc9
--- /dev/null
+++ b/contrib/sdk/sources/sound/Tupfile.lua
@@ -0,0 +1,18 @@
+if tup.getconfig("NO_FASM") ~= "" then return end
+
+SOURCES = {
+    "src/*.asm",
+    extra_inputs = {
+        "src/*.inc"
+    }
+}
+
+OBJS = {
+    extra_inputs = {
+        "symbols"
+    }
+}
+
+tup.append_table(OBJS, tup.foreach_rule(SOURCES, "fasm %f %o", "%B.o"))
+
+tup.rule(OBJS, "ar -cvrs %o %f && objcopy -O elf32-i386 --redefine-syms=symbols %o", {"libsound.a", "<libsound.a>"})
diff --git a/data/Tupfile.lua b/data/Tupfile.lua
index fd3afb2d1..700f54a97 100644
--- a/data/Tupfile.lua
+++ b/data/Tupfile.lua
@@ -184,7 +184,8 @@ extra_files = {
  {"kolibrios/develop/oberon07/lib/KolibriOS/", SRC_PROGS .. "/develop/oberon07/lib/KolibriOS/*"},
  {"kolibrios/develop/oberon07/lib/Math/", SRC_PROGS .. "/develop/oberon07/lib/Math/*"},
  {"kolibrios/develop/oberon07/samples/", SRC_PROGS .. "/develop/oberon07/samples/KolibriOS/*"},
- {"kolibrios/develop/tcc/lib/", SRC_PROGS ..  "/develop/ktcc/bin/lib/*"},
+ {"kolibrios/develop/tcc/lib/", SRC_PROGS ..  "/develop/ktcc/bin/lib/*.def"},
+ {"kolibrios/develop/tcc/lib/libSDL.a", SRC_PROGS .. "/develop/ktcc/bin/lib/libSDL.a"},
  {"kolibrios/develop/tcc/include/", SRC_PROGS ..  "/develop/ktcc/libc.obj/include/*"},
  {"kolibrios/develop/tcc/include/clayer/", SRC_PROGS ..  "/develop/ktcc/libc.obj/include/clayer/*"},
  {"kolibrios/develop/tcc/include/cryptal/", SRC_PROGS .. "/develop/ktcc/libc.obj/include/cryptal/*"},
@@ -634,7 +635,10 @@ tup.append_table(extra_files, {
  {"kolibrios/utils/AMDtemp", VAR_PROGS .. "/system/amd_temp_view/AMDtemp"},
  {"kolibrios/utils/kfm/kfm", VAR_PROGS .. "/fs/kfm/kfm"},
  {"kolibrios/utils/tedit/t_edit", VAR_PROGS .. "/other/t_edit/t_edit"},
- {"kolibrios/3D/blocks/block.bin", VAR_PROGS .. "/bcc32/games/blocks/block.bin"}
+ {"kolibrios/3D/blocks/block.bin", VAR_PROGS .. "/bcc32/games/blocks/block.bin"},
+ {"kolibrios/develop/tcc/lib/crt0.o", VAR_PROGS ..  "/develop/ktcc/bin/lib/crt0.o", group = "../programs/develop/ktcc/<crt0.o>"},
+ {"kolibrios/develop/tcc/lib/tiny.o", VAR_PROGS ..  "/develop/ktcc/bin/lib/tiny.o", group = "../programs/develop/ktcc/<tiny.o>"},
+ {"kolibrios/develop/tcc/lib/libsound.a", VAR_PROGS ..  "/develop/ktcc/bin/lib/libsound.a", group = "../programs/develop/ktcc/<libsound.a>"}
 })
 -- For russian build, add russian-only programs.
 if build_type == "ru_RU" then tup.append_table(img_files, {
@@ -719,29 +723,41 @@ tup.append_table(extra_files, {
 })
 end -- tup.getconfig('NO_MSVC') ~= 'full'
 
--- Programs that require TCC to compile.
+-- Programs that require TCC to compile. TCC programs that link executables
+-- additionally need FASM (for crt0.o, tiny.o, libtcc1.a). LIBC.OBJ is a
+-- relocatable TCC translation unit and does not require FASM.
 if tup.getconfig('NO_TCC') ~= 'full' then
+if tup.getconfig('NO_FASM') ~= 'full' then
 tup.append_table(img_files, {
  {"NETWORK/WHOIS", VAR_PROGS .. "/network/whois/whois"},
  {"SHELL", VAR_PROGS .. "/system/shell/shell"},
  {"GAMES/DINO", VAR_PROGS .. "/games/dino/dino"},
  {"GAMES/FLPYBIRD", VAR_PROGS .. "/games/flpybird/flpybird"},
+})
+end -- tup.getconfig('NO_FASM') ~= 'full'
+tup.append_table(img_files, {
  {"LIB/LIBC.OBJ", VAR_PROGS .. "/develop/ktcc/libc.obj/source/libc.obj"},
 })
+if tup.getconfig('NO_FASM') ~= 'full' then
 tup.append_table(extra_files, {
  {"kolibrios/utils/thashview", VAR_PROGS .. "/other/TinyHashView/thashview"},
  {"kolibrios/demos/kmatrix", VAR_PROGS .. "/demos/kmatrix/kmatrix"},
  {"kolibrios/utils/graph", VAR_PROGS .. "/other/graph/branches/tcc_current/graph"},
  {"kolibrios/develop/TinyBasic/TinyBasic", VAR_PROGS .. "/develop/tinybasic-1.0.4/tinybasic"},
- {"kolibrios/develop/TinyBasic/bas/", SRC_PROGS .. "/develop/tinybasic-1.0.4/bas/*"},
- {"kolibrios/develop/TinyBasic/TinyBasic.man", SRC_PROGS .. "/develop/tinybasic-1.0.4/doc/tinybasic.man"},
  {"kolibrios/utils/passwordgen", VAR_PROGS .. "/other/PasswordGen/passwordgen"},
  {"kolibrios/utils/kruler", VAR_PROGS .. "/other/kruler/kruler"},
- {"kolibrios/media/qr_tool", SRC_PROGS .. "/media/qr_tool/qr_tool"},
  {"kolibrios/utils/weather", VAR_PROGS .. "/other/Weather/weather"},
- {"kolibrios/settings/weather.json", SRC_PROGS .. "/other/Weather/weather.json"},
  {"kolibrios/utils/man2html", VAR_PROGS .."/other/man2html/man2html"},
 })
+end -- tup.getconfig('NO_FASM') ~= 'full'
+tup.append_table(extra_files, {
+ {"kolibrios/develop/TinyBasic/bas/", SRC_PROGS .. "/develop/tinybasic-1.0.4/bas/*"},
+ {"kolibrios/develop/TinyBasic/TinyBasic.man", SRC_PROGS .. "/develop/tinybasic-1.0.4/doc/tinybasic.man"},
+ {"kolibrios/media/qr_tool", SRC_PROGS .. "/media/qr_tool/qr_tool"},
+ {"kolibrios/settings/weather.json", SRC_PROGS .. "/other/Weather/weather.json"},
+ {"kolibrios/develop/tcc/lib/libshell.a", VAR_PROGS .. "/develop/ktcc/bin/lib/libshell.a", group="../programs/develop/ktcc/<libshell.a>"},
+ {"kolibrios/develop/tcc/lib/libcryptal.a", VAR_PROGS .. "/develop/ktcc/bin/lib/libcryptal.a", group="../programs/develop/ktcc/<libcryptal.a>"}
+})
 end -- tup.getconfig('NO_TCC') ~= 'full'
 
 -- Programs that require oberon07 compiler.
@@ -808,6 +824,13 @@ if tup.getconfig('NO_NASM') ~= 'full' then
    {"kolibrios/emul/dgen/dgenrc.html", SRC_PROGS .. "/emulator/dgen-sdl-1.33/dgenrc.html"},
   })
 end
+
+if tup.getconfig("NO_FASM") ~= "full" and tup.getconfig("NO_TCC") ~= "full" then
+  tup.append_table(extra_files, {
+    {"kolibrios/develop/tcc/lib/libtcc1.a", VAR_PROGS .. "/develop/ktcc/bin/lib/libtcc1.a", group="../programs/develop/ktcc/<libtcc1.a>"}
+  })
+end
+
 -- For russian build, add russian-only programs.
 if build_type == "ru_RU" then tup.append_table(extra_files, {
  {"kolibrios/games/21days", VAR_PROGS .. "/games/21days/21days"},
diff --git a/programs/demos/kmatrix/Tupfile.lua b/programs/demos/kmatrix/Tupfile.lua
index 025efea41..4d2361b8e 100755
--- a/programs/demos/kmatrix/Tupfile.lua
+++ b/programs/demos/kmatrix/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 
 HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../.." or tup.getconfig("HELPERDIR")
 tup.include(HELPERDIR .. "/use_tcc.lua")
diff --git a/programs/develop/ktcc/Tupfile.lua b/programs/develop/ktcc/Tupfile.lua
new file mode 100644
index 000000000..6befab330
--- /dev/null
+++ b/programs/develop/ktcc/Tupfile.lua
@@ -0,0 +1,36 @@
+local LIBS = {}
+
+if tup.getconfig("NO_FASM") == "" then
+    tup.append_table(LIBS, {
+        tup.getcwd() .. "/libc.obj/source/crt0.o",
+        tup.getcwd() .. "/lib/tiny/tiny.o",
+    })
+end
+
+if tup.getconfig("NO_TCC") == "" then
+    tup.append_table(LIBS, {
+        tup.getcwd() .. "/lib/libcryptal/libcryptal.a",
+        tup.getcwd() .. "/lib/libshell/libshell.a",
+    })
+end
+
+if tup.getconfig("NO_FASM") == "" and tup.getconfig("NO_TCC") == "" then
+    tup.append_table(LIBS, {
+        tup.getcwd() .. "/libc.obj/source/libtcc1/libtcc1.a",
+    })
+end
+
+tup.foreach_rule(LIBS, "cp %f %o", { tup.getcwd() .. "/bin/lib/%b", "<%b>" })
+
+-- libsound.a lives in another subtree (contrib/), so reference its group
+-- explicitly via extra_inputs to keep Tup ordering correct across trees.
+if tup.getconfig("NO_FASM") == "" then
+    tup.rule(
+        {
+            "../../../contrib/sdk/sources/sound/libsound.a",
+            extra_inputs = { "../../../contrib/sdk/sources/sound/<libsound.a>" },
+        },
+        "cp %f %o",
+        { tup.getcwd() .. "/bin/lib/libsound.a", "<libsound.a>" }
+    )
+end
diff --git a/programs/develop/ktcc/bin/lib/crt0.o b/programs/develop/ktcc/bin/lib/crt0.o
deleted file mode 100644
index b857c8056..000000000
Binary files a/programs/develop/ktcc/bin/lib/crt0.o and /dev/null differ
diff --git a/programs/develop/ktcc/bin/lib/libcryptal.a b/programs/develop/ktcc/bin/lib/libcryptal.a
deleted file mode 100644
index 59467f166..000000000
Binary files a/programs/develop/ktcc/bin/lib/libcryptal.a and /dev/null differ
diff --git a/programs/develop/ktcc/bin/lib/libshell.a b/programs/develop/ktcc/bin/lib/libshell.a
deleted file mode 100644
index 582aa71f6..000000000
Binary files a/programs/develop/ktcc/bin/lib/libshell.a and /dev/null differ
diff --git a/programs/develop/ktcc/bin/lib/libsound.a b/programs/develop/ktcc/bin/lib/libsound.a
deleted file mode 100644
index de48e1352..000000000
Binary files a/programs/develop/ktcc/bin/lib/libsound.a and /dev/null differ
diff --git a/programs/develop/ktcc/bin/lib/libtcc1.a b/programs/develop/ktcc/bin/lib/libtcc1.a
deleted file mode 100644
index 77e05da5e..000000000
Binary files a/programs/develop/ktcc/bin/lib/libtcc1.a and /dev/null differ
diff --git a/programs/develop/ktcc/bin/lib/tiny.o b/programs/develop/ktcc/bin/lib/tiny.o
deleted file mode 100644
index af83c8ef3..000000000
Binary files a/programs/develop/ktcc/bin/lib/tiny.o and /dev/null differ
diff --git a/programs/develop/ktcc/lib/libcryptal/Tupfile.lua b/programs/develop/ktcc/lib/libcryptal/Tupfile.lua
new file mode 100644
index 000000000..09194f672
--- /dev/null
+++ b/programs/develop/ktcc/lib/libcryptal/Tupfile.lua
@@ -0,0 +1,23 @@
+if tup.getconfig("NO_TCC") ~= "" then return end
+
+HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../../../.." or tup.getconfig("HELPERDIR")
+tup.include(HELPERDIR .. "/use_tcc.lua")
+
+LIBC_INCLUDE = "../../libc.obj/include"
+
+CFLAGS += "-c -I. -I" .. LIBC_INCLUDE
+
+SOURCES = {
+    "*.c",
+    extra_inputs = {
+        "memory.h",
+        LIBC_INCLUDE .. "/cryptal/*",
+        LIBC_INCLUDE .. "/string.h",
+        LIBC_INCLUDE .. "/stdlib.h",
+        LIBC_INCLUDE .. "/stdio.h",
+    }
+}
+
+compile_tcc(SOURCES)
+
+tup.rule(OBJS, "ar -rcs %o %f", "libcryptal.a")
diff --git a/programs/develop/ktcc/lib/libshell/Tupfile.lua b/programs/develop/ktcc/lib/libshell/Tupfile.lua
new file mode 100644
index 000000000..b34aab08c
--- /dev/null
+++ b/programs/develop/ktcc/lib/libshell/Tupfile.lua
@@ -0,0 +1,24 @@
+if tup.getconfig("NO_TCC") ~= "" then return end
+
+
+HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../../../.." or tup.getconfig("HELPERDIR")
+tup.include(HELPERDIR .. "/use_tcc.lua")
+
+LIBC_INCLUDE = "../../libc.obj/include"
+
+CFLAGS += "-c -I. -I" .. LIBC_INCLUDE
+
+SOURCES = {
+    "*.c",
+    extra_inputs = {
+        LIBC_INCLUDE .. "/shell_api.h",
+        LIBC_INCLUDE .. "/sys/ksys.h",
+        LIBC_INCLUDE .. "/string.h",
+        LIBC_INCLUDE .. "/stdlib.h",
+        LIBC_INCLUDE .. "/stdio.h"
+    }
+}
+
+compile_tcc(SOURCES)
+
+tup.rule(OBJS, "ar -rcs %o %f", "libshell.a")
diff --git a/programs/develop/ktcc/lib/tiny/Tupfile.lua b/programs/develop/ktcc/lib/tiny/Tupfile.lua
new file mode 100644
index 000000000..7832c5d0d
--- /dev/null
+++ b/programs/develop/ktcc/lib/tiny/Tupfile.lua
@@ -0,0 +1,10 @@
+if tup.getconfig("NO_FASM") ~= "" then return end
+
+HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../../../.." or tup.getconfig("HELPERDIR")
+tup.include(HELPERDIR .. "/use_fasm.lua")
+
+FASM_SOURCES = {
+    "tiny.asm",
+}
+
+tup.rule(FASM_SOURCES, FASM .. " %f %o", "%B.o")
diff --git a/programs/develop/ktcc/libc.obj/.gitignore b/programs/develop/ktcc/libc.obj/.gitignore
new file mode 100644
index 000000000..0b0ee0ab8
--- /dev/null
+++ b/programs/develop/ktcc/libc.obj/.gitignore
@@ -0,0 +1,4 @@
+.tup
+*.o
+*.obj
+*.kex
diff --git a/programs/develop/ktcc/libc.obj/lib/crt0.o b/programs/develop/ktcc/libc.obj/lib/crt0.o
deleted file mode 100644
index 598dbd5fc..000000000
Binary files a/programs/develop/ktcc/libc.obj/lib/crt0.o and /dev/null differ
diff --git a/programs/develop/ktcc/libc.obj/source/Tupfile.lua b/programs/develop/ktcc/libc.obj/source/Tupfile.lua
index 380289707..1e54ba545 100755
--- a/programs/develop/ktcc/libc.obj/source/Tupfile.lua
+++ b/programs/develop/ktcc/libc.obj/source/Tupfile.lua
@@ -1,4 +1,8 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+FASM_SRC = {
+    "crt/crt0.asm",
+}
+
+if tup.getconfig("NO_TCC") == "" then
 
 CFLAGS = " -r -nostdinc -nostdlib -DGNUC -D_BUILD_LIBC "
 INCLUDES = " -I../include"
@@ -32,11 +36,17 @@ GAS_SRC = {
     "string/memmove.s"
 }
 
-OBJS = {"libc.c"}
+OBJS = { "libc.c" }
 
-tup.append_table(OBJS,
-  tup.foreach_rule(GAS_SRC, "as --32 %f -o %o", "%B.o")
-)
+tup.append_table(OBJS, tup.foreach_rule(GAS_SRC, "as --32 %f -o %o", "%B.o"))
 
-tup.rule(OBJS, "kos32-tcc" .. CFLAGS .. INCLUDES .. " %f -o %o " .. " && strip %o --strip-unneeded " , "libc.o")
+tup.rule(OBJS, "kos32-tcc" .. CFLAGS .. INCLUDES .. " %f -o %o " .. " && strip %o --strip-unneeded ", "libc.o")
 tup.rule("libc.o", "objconv -fcoff32 %f %o " .. tup.getconfig("KPACK_CMD"), "%B.obj")
+
+end
+
+if tup.getconfig("NO_FASM") == "" then
+
+tup.rule(FASM_SRC, "fasm %f %o", "%B.o")
+
+end
diff --git a/programs/develop/ktcc/libc.obj/source/libtcc1/Tupfile.lua b/programs/develop/ktcc/libc.obj/source/libtcc1/Tupfile.lua
new file mode 100644
index 000000000..dc4a0ebdb
--- /dev/null
+++ b/programs/develop/ktcc/libc.obj/source/libtcc1/Tupfile.lua
@@ -0,0 +1,25 @@
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
+
+local helperPath = "../../../../.."
+HELPERDIR = (tup.getconfig("HELPERDIR") == "") and helperPath or tup.getconfig("HELPERDIR")
+tup.include(HELPERDIR .. "/use_tcc.lua")
+tup.include(HELPERDIR .. "/use_fasm.lua")
+
+TCC_SOURCES = {
+    "libtcc1.c",
+}
+
+FASM_SOURCES = {
+    "memcpy.asm",
+    "memmove.asm",
+    "memset.asm",
+    extra_inputs = {
+        helperPath .. "/proc32.inc"
+    }
+}
+
+compile_tcc(TCC_SOURCES)
+
+tup.append_table(OBJS, tup.foreach_rule(FASM_SOURCES, FASM .. " %f %o", "%B.o"))
+
+tup.rule(OBJS, "ar -rcs %o %f", "libtcc1.a")
diff --git a/programs/develop/libraries/kos_mbedtls/programs/ssl/Tupfile.lua b/programs/develop/libraries/kos_mbedtls/programs/ssl/Tupfile.lua
index fe493c6aa..7f9b6b489 100644
--- a/programs/develop/libraries/kos_mbedtls/programs/ssl/Tupfile.lua
+++ b/programs/develop/libraries/kos_mbedtls/programs/ssl/Tupfile.lua
@@ -1,5 +1,4 @@
-if tup.getconfig("NO_FASM") ~= "" then return end
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_FASM") ~= "" or tup.getconfig("NO_TCC") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../../../"
diff --git a/programs/develop/tinybasic-1.0.4/Tupfile.lua b/programs/develop/tinybasic-1.0.4/Tupfile.lua
index 7693aeb86..e4db2333a 100644
--- a/programs/develop/tinybasic-1.0.4/Tupfile.lua
+++ b/programs/develop/tinybasic-1.0.4/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/games/dino/Tupfile.lua b/programs/games/dino/Tupfile.lua
index 994138718..431019650 100644
--- a/programs/games/dino/Tupfile.lua
+++ b/programs/games/dino/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/games/flpybird/Tupfile.lua b/programs/games/flpybird/Tupfile.lua
index 08b0c2c39..ee22dd5cd 100644
--- a/programs/games/flpybird/Tupfile.lua
+++ b/programs/games/flpybird/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/network/whois/Tupfile.lua b/programs/network/whois/Tupfile.lua
index 5186b20be..c43f581ca 100644
--- a/programs/network/whois/Tupfile.lua
+++ b/programs/network/whois/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/other/PasswordGen/Tupfile.lua b/programs/other/PasswordGen/Tupfile.lua
index 2b6e84317..1428d9982 100644
--- a/programs/other/PasswordGen/Tupfile.lua
+++ b/programs/other/PasswordGen/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/other/TinyHashView/Tupfile.lua b/programs/other/TinyHashView/Tupfile.lua
index 53fe9d49b..42a0276bb 100644
--- a/programs/other/TinyHashView/Tupfile.lua
+++ b/programs/other/TinyHashView/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
@@ -7,4 +7,4 @@ tup.include(HELPERDIR .. "/use_tcc.lua")
 
 LIBS = "-lcryptal -lbox_lib -ldialog"
 
-link_tcc({"thashview.c"}, "thashview"); 
+link_tcc({"thashview.c"}, "thashview", {"cryptal"});
diff --git a/programs/other/Weather/Tupfile.lua b/programs/other/Weather/Tupfile.lua
index 58a05df78..8377b0610 100644
--- a/programs/other/Weather/Tupfile.lua
+++ b/programs/other/Weather/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/other/graph/branches/tcc_current/Tupfile.lua b/programs/other/graph/branches/tcc_current/Tupfile.lua
index e766b6d78..dd62e1ce3 100755
--- a/programs/other/graph/branches/tcc_current/Tupfile.lua
+++ b/programs/other/graph/branches/tcc_current/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 
 HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../../../.." or tup.getconfig("HELPERDIR")
 tup.include(HELPERDIR .. "/use_tcc.lua")
diff --git a/programs/other/man2html/Tupfile.lua b/programs/other/man2html/Tupfile.lua
index acb3a1b10..91fa1f950 100644
--- a/programs/other/man2html/Tupfile.lua
+++ b/programs/other/man2html/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 if tup.getconfig("HELPERDIR") == ""
 then
   HELPERDIR = "../../../programs"
diff --git a/programs/system/shell/Tupfile.lua b/programs/system/shell/Tupfile.lua
index 8519d980a..f8a3da486 100644
--- a/programs/system/shell/Tupfile.lua
+++ b/programs/system/shell/Tupfile.lua
@@ -1,4 +1,4 @@
-if tup.getconfig("NO_TCC") ~= "" then return end
+if tup.getconfig("NO_TCC") ~= "" or tup.getconfig("NO_FASM") ~= "" then return end
 
 HELPERDIR = (tup.getconfig("HELPERDIR") == "") and "../.." or tup.getconfig("HELPERDIR")
 tup.include(HELPERDIR .. "/use_tcc.lua")
diff --git a/programs/use_tcc.lua b/programs/use_tcc.lua
index 8beb6a793..7e32dc2ca 100644
--- a/programs/use_tcc.lua
+++ b/programs/use_tcc.lua
@@ -1,19 +1,70 @@
-TCC = "kos32-tcc -B" .. tup.getcwd().. "/develop/ktcc/bin"
-
-CFLAGS = "-I" .. tup.getcwd().. "/develop/ktcc/libc.obj/include "
-LFLAGS = ""
-LIBS = ""
-
-OBJS = {}
-
-function compile_tcc(input, output)
-  if not output then output = '%B.o' end
-  tup.append_table(OBJS,
-        tup.foreach_rule(input, TCC .. " -c " .. CFLAGS .. " %f -o %o", output)
-  )
-end
-
-function link_tcc(input, output)
-  if not output then input,output = OBJS,input end
-  tup.rule(input, TCC .. " " .. CFLAGS .. " " .. LFLAGS .. " %f -o %o " .. LIBS .. " " .. tup.getconfig("KPACK_CMD"), output)
-end
+KTCC_TRUNK = tup.getcwd() .. "/develop/ktcc/"
+
+TCC = "kos32-tcc -B" .. tup.getvariantdir() .. "/develop/ktcc/bin"
+
+CFLAGS = "-I" .. KTCC_TRUNK .. "libc.obj/include -L" .. KTCC_TRUNK .. "bin/lib"
+LFLAGS = ""
+LIBS = ""
+
+OBJS = {}
+
+-- Mandatory libs: every TCC-linked program transitively depends on these
+-- (kos32-tcc looks them up automatically from -B<bin>/lib/).
+LIST_OF_LIBS = {}
+
+-- Optional libs: requested by individual programs via the third argument
+-- of link_tcc, e.g. link_tcc(src, out, {"cryptal"}). Only entries that the
+-- current toolchain configuration can actually produce are exposed here.
+OPTIONAL_LIBS = {}
+
+if tup.getconfig("NO_FASM") == "" then
+  tup.append_table(LIST_OF_LIBS, { "crt0.o", "tiny.o" })
+  OPTIONAL_LIBS.sound = "libsound.a"
+end
+
+if tup.getconfig("NO_TCC") == "" then
+  OPTIONAL_LIBS.cryptal = "libcryptal.a"
+  OPTIONAL_LIBS.shell   = "libshell.a"
+end
+
+if tup.getconfig("NO_FASM") == "" and tup.getconfig("NO_TCC") == "" then
+  tup.append_table(LIST_OF_LIBS, { "libtcc1.a" })
+end
+
+function compile_tcc(input, output)
+  if not output then output = '%B.o' end
+  tup.append_table(OBJS,
+    tup.foreach_rule(input, TCC .. " -c " .. CFLAGS .. " %f -o %o", output)
+  )
+end
+
+function link_tcc(input, output, libs)
+  if not output then input, output = OBJS, input end
+
+  if type(input) ~= "table" then
+    input = { input }
+  end
+
+  if not input.extra_inputs then
+    input.extra_inputs = {}
+  end
+
+  for _, lib in pairs(LIST_OF_LIBS) do
+    table.insert(input.extra_inputs, KTCC_TRUNK .. "<" .. lib .. ">")
+  end
+
+  if libs then
+    for _, name in pairs(libs) do
+      local libfile = OPTIONAL_LIBS[name]
+      if libfile then
+        table.insert(input.extra_inputs, KTCC_TRUNK .. "<" .. libfile .. ">")
+      end
+    end
+  end
+
+  table.insert(input.extra_inputs, KTCC_TRUNK .. "bin/lib/*.def")
+
+  tup.rule(input,
+    TCC .. " " .. CFLAGS .. " " .. LFLAGS .. " " .. "%f -o %o " .. LIBS .. " " .. tup.getconfig("KPACK_CMD"),
+    output)
+end