diff --git a/compiler/ccgtypes.nim b/compiler/ccgtypes.nim
index a3debdb0d65f..a3c3c2a85005 100644
--- a/compiler/ccgtypes.nim
+++ b/compiler/ccgtypes.nim
@@ -81,7 +81,6 @@ proc fillBackendName(m: BModule; s: PSym) =
       result.add '_'
       result.add(idOrSig(s, m.module.name.s.mangle, m.sigConflicts, m.config))
     s.loc.snippet = result
-    writeMangledName(m.ndi, s, m.config)
 
 proc fillParamName(m: BModule; s: PSym) =
   if s.loc.snippet == "":
@@ -105,7 +104,6 @@ proc fillParamName(m: BModule; s: PSym) =
     # That would lead to either needing to reload `proxy` or to overwrite the
     # executable file for the main module, which is running (or both!) -> error.
     s.loc.snippet = res.rope
-    writeMangledName(m.ndi, s, m.config)
 
 proc fillLocalName(p: BProc; s: PSym) =
   assert s.kind in skLocalVars+{skTemp}
@@ -121,7 +119,6 @@ proc fillLocalName(p: BProc; s: PSym) =
       result.add "_" & rope(counter+1)
     p.sigConflicts.inc(key)
     s.loc.snippet = result
-    if s.kind != skTemp: writeMangledName(p.module.ndi, s, p.config)
 
 proc scopeMangledParam(p: BProc; param: PSym) =
   ## parameter generation only takes BModule, not a BProc, so we have to
diff --git a/compiler/cgen.nim b/compiler/cgen.nim
index 7e7f7258f2ea..e330033f55f3 100644
--- a/compiler/cgen.nim
+++ b/compiler/cgen.nim
@@ -14,7 +14,7 @@ import
   nversion, nimsets, msgs, bitsets, idents, types,
   ccgutils, ropes, wordrecg, treetab, cgmeth,
   rodutils, renderer, cgendata, aliases,
-  lowerings, ndi, lineinfos, pathutils, transf,
+  lowerings, lineinfos, pathutils, transf,
   injectdestructors, astmsgs, modulepaths, pushpoppragmas,
   mangleutils
 
@@ -2129,9 +2129,6 @@ proc rawNewModule(g: BModuleList; module: PSym, filename: AbsoluteFile): BModule
   if sfSystemModule in module.flags:
     incl result.flags, preventStackTrace
     excl(result.preInitProc.options, optStackTrace)
-  let ndiName = if optCDebug in g.config.globalOptions: changeFileExt(completeCfilePath(g.config, filename), "ndi")
-                else: AbsoluteFile""
-  open(result.ndi, ndiName, g.config)
 
 proc rawNewModule(g: BModuleList; module: PSym; conf: ConfigRef): BModule =
   result = rawNewModule(g, module, AbsoluteFile toFullPath(conf, module.position.FileIndex))
@@ -2261,7 +2258,6 @@ proc shouldRecompile(m: BModule; code: Rope, cfile: Cfile): bool =
 # it would generate multiple 'main' procs, for instance.
 
 proc writeModule(m: BModule, pending: bool) =
-  template onExit() = close(m.ndi, m.config)
   let cfile = getCFile(m)
   if moduleHasChanged(m.g.graph, m.module):
     genInitCode(m)
@@ -2279,12 +2275,10 @@ proc writeModule(m: BModule, pending: bool) =
     when hasTinyCBackend:
       if m.config.cmd == cmdTcc:
         tccgen.compileCCode($code, m.config)
-        onExit()
         return
 
     if not shouldRecompile(m, code, cf): cf.flags = {CfileFlag.Cached}
     addFileToCompile(m.config, cf)
-  onExit()
 
 proc updateCachedModule(m: BModule) =
   let cfile = getCFile(m)
diff --git a/compiler/cgendata.nim b/compiler/cgendata.nim
index 5368e9dc7518..7bc273df300d 100644
--- a/compiler/cgendata.nim
+++ b/compiler/cgendata.nim
@@ -11,7 +11,7 @@
 
 import
   ast, ropes, options,
-  ndi, lineinfos, pathutils, modulegraphs
+  lineinfos, pathutils, modulegraphs
 
 import std/[intsets, tables, sets]
 
@@ -172,7 +172,6 @@ type
                                              # OpenGL wrapper
     sigConflicts*: CountTable[SigHash]
     g*: BModuleList
-    ndi*: NdiFile
 
 template config*(m: BModule): ConfigRef = m.g.config
 template config*(p: BProc): ConfigRef = p.module.g.config
diff --git a/compiler/ndi.nim b/compiler/ndi.nim
deleted file mode 100644
index cc18ab39fdd7..000000000000
--- a/compiler/ndi.nim
+++ /dev/null
@@ -1,52 +0,0 @@
-#
-#
-#           The Nim Compiler
-#        (c) Copyright 2017 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## This module implements the generation of ``.ndi`` files for better debugging
-## support of Nim code. "ndi" stands for "Nim debug info".
-
-import ast, msgs, ropes, options, pathutils
-
-when defined(nimPreviewSlimSystem):
-  import std/[syncio, assertions]
-
-type
-  NdiFile* = object
-    enabled: bool
-    f: File
-    buf: string
-    filename: AbsoluteFile
-    syms: seq[PSym]
-
-proc doWrite(f: var NdiFile; s: PSym; conf: ConfigRef) =
-  f.buf.setLen 0
-  f.buf.addInt s.info.line.int
-  f.buf.add "\t"
-  f.buf.addInt s.info.col.int
-  f.f.write(s.name.s, "\t")
-  f.f.writeRope(s.loc.snippet)
-  f.f.writeLine("\t", toFullPath(conf, s.info), "\t", f.buf)
-
-template writeMangledName*(f: NdiFile; s: PSym; conf: ConfigRef) =
-  if f.enabled: f.syms.add s
-
-proc open*(f: var NdiFile; filename: AbsoluteFile; conf: ConfigRef) =
-  f.enabled = not filename.isEmpty
-  if f.enabled:
-    f.filename = filename
-    f.buf = newStringOfCap(20)
-
-proc close*(f: var NdiFile, conf: ConfigRef) =
-  if f.enabled:
-    f.f = open(f.filename.string, fmWrite, 8000)
-    doAssert f.f != nil, f.filename.string
-    for s in f.syms:
-      doWrite(f, s, conf)
-    close(f.f)
-    f.syms.reset
-    f.filename.reset