diff --git a/build.cm b/build.cm
index 333e1014..bd99429d 100644
--- a/build.cm
+++ b/build.cm
@@ -26,16 +26,18 @@ function get_local_dir() {
 }
 
 // Replace sigils in a string
-// Currently supports: $LOCAL -> .cell/local full path
-function replace_sigils(str) {
-  return replace(str, '$LOCAL', get_local_dir())
+// Supports: $LOCAL -> .cell/local, $PACKAGE -> package dir (if provided)
+function replace_sigils(str, pkg_dir) {
+  var r = replace(str, '$LOCAL', get_local_dir())
+  if (pkg_dir) r = replace(r, '$PACKAGE', pkg_dir)
+  return r
 }
 
 // Replace sigils in an array of flags
-function replace_sigils_array(flags) {
+function replace_sigils_array(flags, pkg_dir) {
   var result = []
   arrfor(flags, function(flag) {
-    push(result, replace_sigils(flag))
+    push(result, replace_sigils(flag, pkg_dir))
   })
   return result
 }
@@ -101,8 +103,9 @@ Build.ensure_dir = ensure_dir
 
 // Compile a single C file for a package
 // Returns the object file path (content-addressed in .cell/build)
-Build.compile_file = function(pkg, file, target, buildtype) {
-  var _buildtype = buildtype || 'release'
+Build.compile_file = function(pkg, file, target, opts) {
+  var _opts = opts || {}
+  var _buildtype = _opts.buildtype || 'release'
   var pkg_dir = shop.get_package_dir(pkg)
   var src_path = pkg_dir + '/' + file
   var core_dir = null
@@ -112,8 +115,8 @@ Build.compile_file = function(pkg, file, target, buildtype) {
     return null
   }
 
-  // Get flags (with sigil replacement)
-  var cflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'CFLAGS', target))
+  // Use pre-fetched cflags if provided, otherwise fetch them
+  var cflags = _opts.cflags || replace_sigils_array(pkg_tools.get_flags(pkg, 'CFLAGS', target), pkg_dir)
   var target_cflags = toolchains[target].c_args || []
   var cc = toolchains[target].c
 
@@ -144,8 +147,12 @@ Build.compile_file = function(pkg, file, target, buildtype) {
   // Add package CFLAGS (resolve relative -I paths)
   arrfor(cflags, function(flag) {
     var f = flag
+    var ipath = null
     if (starts_with(f, '-I') && !starts_with(f, '-I/')) {
-      f = '-I"' + pkg_dir + '/' + text(f, 2) + '"'
+      ipath = text(f, 2)
+      if (!starts_with(ipath, pkg_dir)) {
+        f = '-I"' + pkg_dir + '/' + ipath + '"'
+      }
     }
     push(cmd_parts, f)
   })
@@ -179,6 +186,7 @@ Build.compile_file = function(pkg, file, target, buildtype) {
   var ret = os.system(full_cmd)
   if (ret != 0) {
     print('Compilation failed: ' + file)
+    print('Command: ' + full_cmd)
     return null
   }
 
@@ -193,8 +201,12 @@ Build.build_package = function(pkg, target, exclude_main, buildtype) {
   var c_files = pkg_tools.get_c_files(pkg, _target, exclude_main)
   var objects = []
 
+  // Pre-fetch cflags once
+  var pkg_dir = shop.get_package_dir(pkg)
+  var cached_cflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'CFLAGS', _target), pkg_dir)
+
   arrfor(c_files, function(file) {
-    var obj = Build.compile_file(pkg, file, _target, _buildtype)
+    var obj = Build.compile_file(pkg, file, _target, {buildtype: _buildtype, cflags: cached_cflags})
     push(objects, obj)
   })
   
@@ -235,7 +247,7 @@ Build.build_module_dylib = function(pkg, file, target, opts) {
   var _target = target || Build.detect_host_target()
   var _buildtype = _opts.buildtype || 'release'
   var _extra = _opts.extra_objects || []
-  var obj = Build.compile_file(pkg, file, _target, _buildtype)
+  var obj = Build.compile_file(pkg, file, _target, {buildtype: _buildtype, cflags: _opts.cflags})
   if (!obj) return null
 
   var tc = toolchains[_target]
@@ -245,13 +257,17 @@ Build.build_module_dylib = function(pkg, file, target, opts) {
   var pkg_dir = shop.get_package_dir(pkg)
 
   // Get link flags
-  var ldflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'LDFLAGS', _target))
+  var ldflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'LDFLAGS', _target), pkg_dir)
   var target_ldflags = tc.c_link_args || []
   var resolved_ldflags = []
   arrfor(ldflags, function(flag) {
     var f = flag
+    var lpath = null
     if (starts_with(f, '-L') && !starts_with(f, '-L/')) {
-      f = '-L"' + pkg_dir + '/' + text(f, 2) + '"'
+      lpath = text(f, 2)
+      if (!starts_with(lpath, pkg_dir)) {
+        f = '-L"' + pkg_dir + '/' + lpath + '"'
+      }
     }
     push(resolved_ldflags, f)
   })
@@ -333,17 +349,23 @@ Build.build_dynamic = function(pkg, target, buildtype) {
   var c_files = pkg_tools.get_c_files(pkg, _target, true)
   var results = []
 
+  // Pre-fetch cflags once to avoid repeated TOML reads
+  var pkg_dir = shop.get_package_dir(pkg)
+  var cached_cflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'CFLAGS', _target), pkg_dir)
+
+  log.console(`CFLAGS ${pkg}: ${text(cached_cflags, '|')}`)
+
   // Compile support sources to cached objects
   var sources = pkg_tools.get_sources(pkg)
   var support_objects = []
   arrfor(sources, function(src_file) {
-    var obj = Build.compile_file(pkg, src_file, _target, _buildtype)
+    var obj = Build.compile_file(pkg, src_file, _target, {buildtype: _buildtype, cflags: cached_cflags})
     push(support_objects, obj)
   })
 
   arrfor(c_files, function(file) {
     var sym_name = shop.c_symbol_for_file(pkg, file)
-    var dylib = Build.build_module_dylib(pkg, file, _target, {buildtype: _buildtype, extra_objects: support_objects})
+    var dylib = Build.build_module_dylib(pkg, file, _target, {buildtype: _buildtype, extra_objects: support_objects, cflags: cached_cflags})
     if (dylib) {
       push(results, {file: file, symbol: sym_name, dylib: dylib})
     }
@@ -378,8 +400,8 @@ Build.build_static = function(packages, target, output, buildtype) {
     })
 
     // Collect LDFLAGS (with sigil replacement)
-    var ldflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'LDFLAGS', _target))
     var pkg_dir = shop.get_package_dir(pkg)
+    var ldflags = replace_sigils_array(pkg_tools.get_flags(pkg, 'LDFLAGS', _target), pkg_dir)
     
     // Deduplicate based on the entire LDFLAGS string for this package
     var ldflags_key = pkg + ':' + text(ldflags, ' ')
@@ -387,8 +409,12 @@ Build.build_static = function(packages, target, output, buildtype) {
       seen_flags[ldflags_key] = true
       arrfor(ldflags, function(flag) {
         var f = flag
+        var lpath = null
         if (starts_with(f, '-L') && !starts_with(f, '-L/')) {
-          f = '-L"' + pkg_dir + '/' + text(f, 2) + '"'
+          lpath = text(f, 2)
+          if (!starts_with(lpath, pkg_dir)) {
+            f = '-L"' + pkg_dir + '/' + lpath + '"'
+          }
         }
         push(all_ldflags, f)
       })
diff --git a/internal/shop.cm b/internal/shop.cm
index dbde2841..7caccf51 100644
--- a/internal/shop.cm
+++ b/internal/shop.cm
@@ -495,6 +495,7 @@ function resolve_mod_fn(path, pkg) {
   if (!fd.is_file(path)) { print(`path ${path} is not a file`); disrupt }
 
   var content = text(fd.slurp(path))
+  if (length(content) == 0) { print(`${path}: empty file`); disrupt }
   var content_key = stone(blob(content))
   var native_result = null
   var cached = null
@@ -1049,6 +1050,7 @@ function fetch_remote_hash(pkg) {
 // Returns the zip blob or null on failure
 function download_zip(pkg, commit_hash) {
   var cache_path = get_cache_path(pkg, commit_hash)
+  ensure_dir(global_shop_path + '/cache')
 
   var download_url = Shop.get_download_url(pkg, commit_hash)
   if (!download_url) {
@@ -1177,8 +1179,10 @@ Shop.extract = function(pkg) {
 
   var zip_blob = get_package_zip(pkg)
 
-  if (!zip_blob)
-    print("No zip blob available for " + pkg); disrupt
+  if (!zip_blob) {
+    print("No zip blob available for " + pkg)
+    disrupt
+  }
 
   // Extract zip for remote package
   install_zip(zip_blob, target_dir)
diff --git a/package.cm b/package.cm
index a4c7e0fa..a2b3d2b1 100644
--- a/package.cm
+++ b/package.cm
@@ -40,8 +40,13 @@ function get_path(name)
   return global_shop_path + '/packages/' + replace(name, '@', '_')
 }
 
+var config_cache = {}
+
 package.load_config = function(name)
 {
+  var cache_key = name || '_project_'
+  if (config_cache[cache_key]) return config_cache[cache_key]
+
   var config_path = get_path(name) + '/cell.toml'
 
   if (!fd.is_file(config_path)) {
@@ -54,9 +59,31 @@ package.load_config = function(name)
 
   var result = toml.decode(content)
   if (!result) {
+    print(`TOML decode returned null for ${config_path}`)
     return {}
   }
 
+  // Validate: if content has [compilation] but decode result doesn't, retry
+  var has_compilation = search(content, '[compilation') != null
+  if (has_compilation && !result.compilation) {
+    print(`TOML decode missing compilation for ${config_path}, retrying`)
+    var retry = 0
+    while (retry < 3 && (!result || !result.compilation)) {
+      result = toml.decode(content)
+      retry = retry + 1
+    }
+    if (!result) return {}
+  }
+
+  if (has_compilation && result.compilation) {
+    var cf = result.compilation.CFLAGS
+    if (cf == null && search(content, 'CFLAGS') != null) {
+      print(`TOML has CFLAGS text but decode missing it for ${config_path}`)
+      print(`compilation keys: ${text(array(result.compilation), ',')}`)
+    }
+  }
+
+  config_cache[cache_key] = result
   return result
 }
 
diff --git a/source/cell.c b/source/cell.c
index 651f4b66..c31380a5 100644
--- a/source/cell.c
+++ b/source/cell.c
@@ -500,6 +500,7 @@ int cell_init(int argc, char **argv)
       core_override = ".";
       mkdir(".cell", 0755);
       mkdir(".cell/build", 0755);
+      mkdir(".cell/cache", 0755);
       mkdir(".cell/packages", 0755);
       /* Ensure .cell/packages/core -> . symlink exists */
       struct stat lst;