diff --git a/compiler/cmdlinehelper.nim b/compiler/cmdlinehelper.nim
index 9fbf4a0b07..7656a11f96 100644
--- a/compiler/cmdlinehelper.nim
+++ b/compiler/cmdlinehelper.nim
@@ -48,18 +48,26 @@ proc loadConfigsAndRunMainCommand*(self: NimProg, cache: IdentCache; conf: Confi
   if self.suggestMode:
     conf.command = "nimsuggest"
 
-  # These defines/options should not be enabled while processing nimscript
-  # bug #4446, #9420, #8991, #9589, #9153
-  undefSymbol(conf.symbols, "profiler")
-  undefSymbol(conf.symbols, "memProfiler")
-  undefSymbol(conf.symbols, "nodejs")
+  when false:
+    # These defines/options should not be enabled while processing nimscript
+    # bug #4446, #9420, #8991, #9589, #9153
+    undefSymbol(conf.symbols, "profiler")
+    undefSymbol(conf.symbols, "memProfiler")
+    undefSymbol(conf.symbols, "nodejs")
 
-  # bug #9120
-  conf.globalOptions.excl(optTaintMode)
+    # bug #9120
+    conf.globalOptions.excl(optTaintMode)
 
-  proc runNimScriptIfExists(path: AbsoluteFile)=
-    if fileExists(path):
-      runNimScript(cache, path, freshDefines = false, conf)
+  template runNimScriptIfExists(path: AbsoluteFile) =
+    let p = path # eval once
+    if fileExists(p):
+      var tempConf = newConfigRef()
+      setDefaultLibpath(tempConf)
+      initDefines(tempConf.symbols)
+      tempConf.command = conf.command
+      tempConf.commandArgs = conf.commandArgs
+      runNimScript(cache, p, freshDefines = false, tempConf)
+      mergeConfigs(conf, tempConf)
 
   # Caution: make sure this stays in sync with `loadConfigs`
   if optSkipSystemConfigFile notin conf.globalOptions:
@@ -88,9 +96,6 @@ proc loadConfigsAndRunMainCommand*(self: NimProg, cache: IdentCache; conf: Confi
         # 'nimsuggest foo.nims' means to just auto-complete the NimScript file
         discard
 
-  # Reload configuration from .cfg file
-  loadConfigs(DefaultConfig, cache, conf)
-
   # now process command line arguments again, because some options in the
   # command line can overwite the config file's settings
   extccomp.initVars(conf)
diff --git a/compiler/options.nim b/compiler/options.nim
index 80d665d62c..52c7d88cd4 100644
--- a/compiler/options.nim
+++ b/compiler/options.nim
@@ -253,6 +253,80 @@ template depConfigFields*(fn) {.dirty.} =
   fn(globalOptions)
   fn(selectedGC)
 
+proc mergeConfigs*(dest, src: ConfigRef) =
+  template merge[T: enum](a, b: T) =
+    a = b
+  template merge[T](a, b: set[T]) =
+    a = a + b
+  template merge(a, b: int) =
+    inc a, b
+  template merge[T](a, b: seq[T]) =
+    for bb in b: a.add b
+  template merge(a, b: string) =
+    a = b
+  template merge[T: AbsoluteFile|AbsoluteDir](a, b: T) =
+    if a.isEmpty and not b.isEmpty: a = b
+
+  template merge[T](a, b: HashSet[T]) =
+    for bb in b: a.incl b
+  template merge(a, b: StringTableRef) =
+    for k, v in b: a[k] = v
+  template merge[T: object](a, b: T) =
+    a = b
+
+  template m(field) =
+    merge(dest.field, src.field)
+
+  m target
+  m options
+  m globalOptions
+  m cmd
+  m selectedGC
+  m verbosity
+  m numberOfProcessors
+  m evalExpr
+  m symbolFiles
+  m cppDefines
+  m headerFile
+  m features
+  m arguments
+  m ideCmd
+  m cCompiler
+  m enableNotes
+  m disableNotes
+  m foreignPackageNotes
+  m notes
+  m errorCounter
+  m hintCounter
+  m warnCounter
+  m errorMax
+  m configVars
+  m symbols
+  m searchPaths
+  m lazyPaths
+  m outFile
+  m prefixDir
+  m libpath
+  m nimcacheDir
+  m dllOverrides
+  m moduleOverrides
+  m command
+  m commandArgs
+  m implicitImports
+  m implicitIncludes
+  m docSeeSrcUrl
+  m cIncludes
+  m cLibs
+  m cLinkedLibs
+  m externalToLink
+  m linkOptionsCmd
+  m compileOptionsCmd
+  m linkOptions
+  m compileOptions
+  m ccompilerpath
+  m toCompile
+  m cppCustomNamespace
+
 const oldExperimentalFeatures* = {implicitDeref, dotOperators, callOperator, parallel}
 
 const