8 files changed, 26 insertions, 1 deletions
diff --git a/compiler/depends.nim b/compiler/depends.nim
index 1dcdec989..7e5dabbd3 100644
--- a/compiler/depends.nim
+++ b/compiler/depends.nim
@@ -16,6 +16,10 @@ import modulegraphs
 import std/[os, strutils, parseutils]
 import std/private/globs
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 type
   TGen = object of PPassContext
     module: PSym
diff --git a/compiler/docgen.nim b/compiler/docgen.nim
index 52bb93c19..8c95692df 100644
--- a/compiler/docgen.nim
+++ b/compiler/docgen.nim
@@ -23,6 +23,10 @@ from uri import encodeUrl
 from std/private/globs import nativeToUnixPath
 from nodejs import findNodeJs
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
+
 const
   exportSection = skField
   docCmdSkip = "skip"
diff --git a/compiler/jsgen.nim b/compiler/jsgen.nim
index 6d34fcae2..60d10f58d 100644
--- a/compiler/jsgen.nim
+++ b/compiler/jsgen.nim
@@ -37,6 +37,10 @@ import
 
 import json, sets, math, tables, intsets, strutils
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
+
 type
   TJSGen = object of PPassContext
     module: PSym
diff --git a/compiler/nim.cfg b/compiler/nim.cfg
index 4a0287cb5..7ed70fb5f 100644
--- a/compiler/nim.cfg
+++ b/compiler/nim.cfg
@@ -5,6 +5,7 @@ hint[XDeclaredButNotUsed]:off
 define:booting
 define:nimcore
 define:nimPreviewFloatRoundtrip
+define:nimPreviewSlimSystem
 
 #import:"$projectpath/testability"
 
diff --git a/compiler/packages.nim b/compiler/packages.nim
index 6ceeb1ccc..d8b97e374 100644
--- a/compiler/packages.nim
+++ b/compiler/packages.nim
@@ -16,6 +16,10 @@
 
 import "." / [options, ast, lineinfos, idents, pathutils, msgs]
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 proc getPackage*(conf: ConfigRef; cache: IdentCache; fileIdx: FileIndex): PSym =
   ## Return a new package symbol.
   ## 
diff --git a/compiler/renderverbatim.nim b/compiler/renderverbatim.nim
index fc74f2322..792079b3f 100644
--- a/compiler/renderverbatim.nim
+++ b/compiler/renderverbatim.nim
@@ -2,6 +2,10 @@ import strutils
 
 import ast, options, msgs
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 const isDebug = false
 when isDebug:
   import renderer
diff --git a/compiler/typesrenderer.nim b/compiler/typesrenderer.nim
index c81ff283e..f59f63659 100644
--- a/compiler/typesrenderer.nim
+++ b/compiler/typesrenderer.nim
@@ -9,6 +9,10 @@
 
 import renderer, strutils, ast, types
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 const defaultParamSeparator* = ","
 
 template mayNormalize(s: string): string =
diff --git a/compiler/vmops.nim b/compiler/vmops.nim
index 7c7f02006..01aa5a4b9 100644
--- a/compiler/vmops.nim
+++ b/compiler/vmops.nim
@@ -32,7 +32,7 @@ from system/formatfloat import addFloatRoundtrip, addFloatSprintf
 
 
 when defined(nimPreviewSlimSystem):
-  import std/[syncio, assertions]
+  import std/syncio
 
 
 # There are some useful procs in vmconv.