diff --git a/uppsrc/ide/Build.cpp b/uppsrc/ide/Build.cpp
index c071abb6a..e9fc2e05e 100644
--- a/uppsrc/ide/Build.cpp
+++ b/uppsrc/ide/Build.cpp
@@ -30,6 +30,7 @@ void Ide::BeginBuilding(bool clear_console)
 {
 	SetupDefaultMethod();
 	HdependTimeDirty();
+	Builder::cmdx_cache.Clear();
 	Renumber();
 	StopDebug();
 	ShowConsole();
diff --git a/uppsrc/ide/Builders/Build.cpp b/uppsrc/ide/Builders/Build.cpp
index 08e80e676..0b69aa660 100644
--- a/uppsrc/ide/Builders/Build.cpp
+++ b/uppsrc/ide/Builders/Build.cpp
@@ -444,6 +444,7 @@ Vector<String> MakeBuild::GetAllLibraries(const Workspace& wspc, int index,
 bool MakeBuild::Build(const Workspace& wspc, String mainparam, String outfile, bool clear_console)
 {
 	InitBlitz();
+	Builder::cmdx_cache.Clear();
 
 	String hfile = outfile + ".xxx";
 	SaveFile(hfile, "");
diff --git a/uppsrc/ide/Core/Builder.cpp b/uppsrc/ide/Core/Builder.cpp
index 9cb89c446..32d6ed88d 100644
--- a/uppsrc/ide/Core/Builder.cpp
+++ b/uppsrc/ide/Core/Builder.cpp
@@ -32,6 +32,8 @@ Time Builder::GetFileTime(const String& path) const
 	return GetFileInfo(path);
 }
 
+VectorMap<String, String> Builder::cmdx_cache;
+
 String Builder::CmdX(const char *s)
 { // expand ` character delimited sections by executing them as commands
 	String r, cmd;
@@ -39,7 +41,15 @@ String Builder::CmdX(const char *s)
 	for(; *s; s++)
 		if(*s == '`') {
 			if(cmdf) {
-				r << Sys(cmd);
+				int q = cmdx_cache.Find(cmd);
+				if(q >= 0)
+					r << cmdx_cache[q];
+				else {
+					String h = Sys(cmd);
+					r << h;
+					cmdx_cache.Add(cmd, h);
+					IdeProcessEvents();
+				}
 				cmd.Clear();
 			}
 			cmdf = !cmdf;
diff --git a/uppsrc/ide/Core/Core.h b/uppsrc/ide/Core/Core.h
index 2896c91bb..55d19e2ec 100644
--- a/uppsrc/ide/Core/Core.h
+++ b/uppsrc/ide/Core/Core.h
@@ -179,6 +179,8 @@ public:
 	virtual bool             IdeConsoleWait() = 0;
 	virtual bool             IdeConsoleWait(int slot) = 0;
 	virtual void             IdeConsoleOnFinish(Event<>  cb) = 0;
+	
+	virtual void             IdeProcessEvents() = 0;
 
 	virtual bool      IdeIsDebug() const = 0;
 	virtual void      IdeEndDebug() = 0;
@@ -243,6 +245,8 @@ bool             IdeConsoleWait();
 bool             IdeConsoleWait(int slot);
 void             IdeConsoleOnFinish(Event<>  cb);
 
+void             IdeProcessEvents();
+
 String GetSourcePackage(const String& path);
 
 String GetDefaultMethod();
@@ -576,6 +580,8 @@ struct Builder {
 	Vector<String>   Macro;
 
 	VectorMap<String, int> tmpfilei; // for naming automatic response files
+	
+	static VectorMap<String, String> cmdx_cache; // caching e.g. pkg-config
 
 	String                 CmdX(const char *s);
 
diff --git a/uppsrc/ide/Core/Ide.cpp b/uppsrc/ide/Core/Ide.cpp
index ff4e18173..263bc87be 100644
--- a/uppsrc/ide/Core/Ide.cpp
+++ b/uppsrc/ide/Core/Ide.cpp
@@ -11,6 +11,8 @@ void PutVerbose(const char *s) { if(the_ide) the_ide->PutVerbose(s); }
 void PutLinking()              { if(the_ide) the_ide->PutLinking(); }
 void PutLinkingEnd(bool ok)    { if(the_ide) the_ide->PutLinkingEnd(ok); }
 
+void IdeProcessEvents()        { if(the_ide) the_ide->IdeProcessEvents(); }
+
 const Workspace& GetIdeWorkspace()
 {
 	if(the_ide)
diff --git a/uppsrc/ide/ide.h b/uppsrc/ide/ide.h
index cc93dd87a..e5a7c7b3f 100644
--- a/uppsrc/ide/ide.h
+++ b/uppsrc/ide/ide.h
@@ -399,6 +399,7 @@ public:
 	virtual   bool             IdeConsoleWait();
 	virtual   bool             IdeConsoleWait(int slot);
 	virtual   void             IdeConsoleOnFinish(Event<>  cb);
+	virtual   void             IdeProcessEvents();
 
 	virtual   bool      IdeIsDebug() const;
 	virtual   void      IdeEndDebug();
diff --git a/uppsrc/ide/idewin.cpp b/uppsrc/ide/idewin.cpp
index 2a18beb2d..318e18d1e 100644
--- a/uppsrc/ide/idewin.cpp
+++ b/uppsrc/ide/idewin.cpp
@@ -135,6 +135,11 @@ void Ide::IdeConsoleOnFinish(Event<>  cb)
 	console.OnFinish(cb);
 }
 
+void Ide::IdeProcessEvents()
+{
+	Ctrl::ProcessEvents();
+}
+
 void Ide::IdeSetRight(Ctrl& ctrl)
 {
 	right.Add(ctrl.SizePos());