diff --git a/.github/workflows/c-cpp.yml b/.github/workflows/c-cpp.yml
index 956bdd5..5ea2cf5 100644
--- a/.github/workflows/c-cpp.yml
+++ b/.github/workflows/c-cpp.yml
@@ -13,7 +13,7 @@ jobs:
     - uses: actions/checkout@v4
 
     - name: Install dependencies
-      run:  sudo apt-get update && sudo apt-get install libtiff-dev libpng-dev libturbojpeg-dev libwebp-dev libavif-dev libmemcached-dev libopenjp2-7-dev
+      run:  sudo apt-get update && sudo apt-get install libfcgi-dev libtiff-dev libpng-dev libturbojpeg-dev libwebp-dev libavif-dev libmemcached-dev libopenjp2-7-dev
 
     - name: Configure
       run: |
diff --git a/configure.ac b/configure.ac
index f3ef1a4..c2ca22b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -314,10 +314,6 @@ if test -n "$kakadu_path"; then
 
 		AC_SUBST(KAKADU_OBJS)
 
-		AC_LANG_PUSH([C++])
-		AC_CHECK_HEADER([thread], [AC_DEFINE(HAVE_STL_THREAD)])
-		AC_LANG_POP([C++])
-
 		AC_CHECK_FUNC([get_nprocs_conf],[AC_DEFINE(NPROCS)])
 	fi
 else
diff --git a/src/JPEGImage.cc b/src/JPEGImage.cc
index a8d4314..30f4c4f 100644
--- a/src/JPEGImage.cc
+++ b/src/JPEGImage.cc
@@ -16,7 +16,6 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-
 #include "JPEGImage.h"
 #include "Logger.h"
 #include <cstdio>
@@ -476,8 +475,8 @@ void JPEGImage::process( unsigned int res, int layers, int xoffset, int yoffset,
       }
     }
 
-    // Free any temporary buffer we may have created
-    if( dst_ptr ) free( dst_ptr );
+    // Free temporary buffer we created for when factor > 1
+    if( buffer ) free( buffer );
   }
 
 }
diff --git a/src/TIFFCompressor.cc b/src/TIFFCompressor.cc
index 2ee33d9..141ecb0 100644
--- a/src/TIFFCompressor.cc
+++ b/src/TIFFCompressor.cc
@@ -41,7 +41,7 @@ extern "C" {
     tiff_mem *memtif = (tiff_mem *) handle;
     
     // Re-allocate extra memory if we don't have enough space
-    if( ((tsize_t) memtif->current + length) > memtif->capacity ){
+    if( (memtif->current + length) > memtif->capacity ){
       memtif->capacity = memtif->capacity + length;
       memtif->buffer = (unsigned char*) realloc( memtif->buffer, memtif->capacity );
     }
@@ -94,11 +94,6 @@ extern "C" {
   static void _unmap( thandle_t handle, tdata_t base, toff_t psize ){
   }
 
-  // Free function - unimplemented as memory handled manually
-  static void _free( tiff_mem *memtif ){
-    return;
-  }
-
 }
 
 
diff --git a/src/TIFFCompressor.h b/src/TIFFCompressor.h
index 3647df9..1650d36 100644
--- a/src/TIFFCompressor.h
+++ b/src/TIFFCompressor.h
@@ -33,7 +33,7 @@ typedef struct {
   unsigned char *buffer;   /// Data buffer
   toff_t current;          /// Current byte position within stream
   toff_t end;              /// Last written byte
-  tsize_t capacity;        /// Allocated buffer size
+  toff_t capacity;         /// Allocated buffer size
 } tiff_mem;
 
 typedef tiff_mem* tiff_mem_ptr;
diff --git a/src/Task.cc b/src/Task.cc
index 9d33391..3d2888b 100644
--- a/src/Task.cc
+++ b/src/Task.cc
@@ -99,7 +99,7 @@ void QLT::run( Session* session, const string& argument ){
   transform( arg.begin(), arg.end(), arg.begin(), ::tolower );
 
   // Check whether we have a compression:quality combination
-  int delimitter = arg.find( ":" );
+  std::string::size_type delimitter = arg.find( ":" );
   if( delimitter != string::npos ){
     string comp = arg.substr( 0, delimitter );
     int                          compression = 0;