diff --git a/Makefile b/Makefile
index fc436956..7f37aed9 100644
--- a/Makefile
+++ b/Makefile
@@ -34,7 +34,6 @@ else
 	else
 		LDFLAGS += -pthread -Wl,--no-as-needed
 	endif
-
 endif
 
 HOSTCC = gcc
@@ -85,7 +84,7 @@ binaries: all
 tests: all
 	
 README.md: $(OBJ)/scripts/+mkdocindex/mkdocindex$(EXT)
-	@echo $(PROGRESSINFO) MKDOC $@
+	@echo $(PROGRESSINFO)MKDOC $@
 	@csplit -s -f$(OBJ)/README. README.md '/<!-- FORMATSSTART -->/' '%<!-- FORMATSEND -->%'
 	@(cat $(OBJ)/README.00 && $< && cat $(OBJ)/README.01) > README.md
 
diff --git a/README.md b/README.md
index 73665387..9798c8e7 100644
--- a/README.md
+++ b/README.md
@@ -125,6 +125,7 @@ choices because they can store multiple types of file system.
 | [`hplif`](doc/disk-hplif.md) | Hewlett-Packard LIF: a variety of disk formats used by HP | 🦄 | 🦄 | LIF  |
 | [`ibm`](doc/disk-ibm.md) | IBM PC: Generic PC 3.5"/5.25" disks | 🦄 | 🦄 | FATFS  |
 | [`icl30`](doc/disk-icl30.md) | ICL Model 30: CP/M; 263kB 35-track DSSD | 🦖 |  | CPMFS  |
+| [`juku`](doc/disk-juku.md) | Juku E5104: CP/M |  |  | CPMFS  |
 | [`mac`](doc/disk-mac.md) | Macintosh: 400kB/800kB 3.5" GCR | 🦄 | 🦄 | MACHFS  |
 | [`micropolis`](doc/disk-micropolis.md) | Micropolis: 100tpi MetaFloppy disks | 🦄 | 🦄 |  |
 | [`ms2000`](doc/disk-ms2000.md) | : MS2000 Microdisk Development System |  |  | MICRODOS  |
diff --git a/build.py b/build.py
index 3b543cfe..de13a623 100644
--- a/build.py
+++ b/build.py
@@ -7,6 +7,11 @@
 import config
 import re
 
+# Hack for building on Fedora/WSL; executables get the .exe extension,
+# build the build system detects it as Linux.
+import build.toolchain
+toolchain.Toolchain.EXE = "$(EXT)"
+
 package(name="protobuf_lib", package="protobuf")
 package(name="z_lib", package="zlib")
 package(name="fmt_lib", package="fmt", fallback="dep/fmt")
diff --git a/build/_sandbox.py b/build/_sandbox.py
index 2450c537..f7667a68 100644
--- a/build/_sandbox.py
+++ b/build/_sandbox.py
@@ -26,7 +26,7 @@ def main():
                 print("link", sf)
             os.makedirs(dirname(sf), exist_ok=True)
             try:
-                os.link(abspath(f), sf)
+                os.symlink(abspath(f), sf)
             except PermissionError:
                 shutil.copy(f, sf)
 
@@ -38,6 +38,11 @@ def main():
             df = dirname(f)
             if df:
                 os.makedirs(df, exist_ok=True)
+
+            try:
+                os.remove(f)
+            except FileNotFoundError:
+                pass
             os.rename(sf, f)
 
 
diff --git a/build/ab.py b/build/ab.py
index bbf947a6..f4e424d6 100644
--- a/build/ab.py
+++ b/build/ab.py
@@ -501,15 +501,17 @@ def emit_rule(self, ins, outs, cmds=[], label=None):
 
         emit(f"OUTS_{outsn}", "=", *fouts, into=lines)
         emit(f"INS_{insn}", "=", *fins, into=lines)
+        emit(name, ":", f"$(OUTS_{outsn})", into=lines)
+        emit(hashfile, ":", into=lines)
+        emit(f"\t@mkdir -p {self.dir}", into=lines)
+        emit(f"\t@touch {hashfile}", into=lines)
         emit(
-            name,
-            ":",
-            hashfile,
             f"$(OUTS_{outsn})",
+            "&:" if len(fouts) > 1 else ":",
+            f"$(INS_{insn})",
+            hashfile,
             into=lines,
         )
-        emit(f"$(OUTS_{outsn})", ":", hashfile, into=lines)
-        emit(hashfile, ":", f"$(INS_{insn})", into=lines)
 
         if label:
             emit("\t$(hide)", "$(ECHO) $(PROGRESSINFO)" + label, into=lines)
@@ -537,9 +539,6 @@ def emit_rule(self, ins, outs, cmds=[], label=None):
         emit(name, ":", *fins, into=lines)
 
     outputFp.write("".join(lines))
-
-    if outs:
-        emit(f"\t$(hide) touch {hashfile}")
     emit("")
 
 
diff --git a/build/c.py b/build/c.py
index 21050393..1a07a3e8 100644
--- a/build/c.py
+++ b/build/c.py
@@ -444,7 +444,7 @@ def programimpl(
     simplerule(
         replaces=self,
         ins=cfiles + libs,
-        outs=[f"={self.localname}$(EXT)"],
+        outs=[f"={self.localname}{toolchain.EXE}"],
         deps=deps,
         label=label,
         commands=commands,
diff --git a/build/toolchain.py b/build/toolchain.py
index b47d3e8a..021ad76d 100644
--- a/build/toolchain.py
+++ b/build/toolchain.py
@@ -1,5 +1,10 @@
+import platform
+
+_is_windows = (platform.system() == "Windows")
+
 class Toolchain:
     PREFIX = ""
+    EXE = ".exe" if _is_windows else ""
 
 
 class HostToolchain(Toolchain):
diff --git a/scripts/build.py b/scripts/build.py
index f9a664cc..aee9e639 100644
--- a/scripts/build.py
+++ b/scripts/build.py
@@ -30,7 +30,12 @@ def protoencode_single(self, name, srcs: Targets, proto, symbol):
         ins=srcs,
         outs=[f"={name}.cc"],
         deps=[r],
-        commands=["$[deps[0]] $[ins] $[outs] " + symbol],
+        commands=[
+            # Materialise symbolic links (for Windows).
+            "cp -L $[ins[0]] $[ins[0]].real",
+            "mv $[ins[0]].real $[ins[0]]",
+            "$[deps[0]] $[ins] $[outs] " + symbol
+        ],
         label="PROTOENCODE",
     )