diff --git a/nix-lib/default.nix b/nix-lib/default.nix
--- a/nix-lib/default.nix
+++ b/nix-lib/default.nix
@@ -89,7 +89,7 @@
           in ''
             echo "linking node dependency ${formatKey dep.key}"
             ${ # we need to create the scope folder, otherwise ln fails
-               lib.optionalString hasScope ''mkdir "${parentfolder}"'' }
+               lib.optionalString hasScope ''mkdir -p "${parentfolder}"'' }
             ln -sT ${dep.drv} "${subfolder}"
             ${yarn2nix}/bin/node-package-tool \
               link-bin \
diff --git a/nix-lib/old-version-dependencies.nix b/nix-lib/old-version-dependencies.nix
--- a/nix-lib/old-version-dependencies.nix
+++ b/nix-lib/old-version-dependencies.nix
@@ -3,14 +3,13 @@
   yarn-lock =
     super.mkDerivation rec {
       pname = "yarn-lock";
-      version = "0.5.0";
+      version = "0.6.2";
       # src = ../../../haskell/yarn-lock;
       src = pkgs.fetchFromGitHub {
         owner = "Profpatsch";
         repo = "yarn-lock";
         rev = version;
-        # rev = "61cc65a858db92e7c0bea861bf279f286c34bb81";
-        sha256 = "007a7n1qqa7cp85bbw00yvkg2ikg1yzj1k8i9bav1bnbk6n7xp7s";
+        sha256 = "06171ya075yx88gfx39z6mh1k1al0qaqrarbas5mv6lrky19bdxs";
       };
       license = lib.licenses.mit;
       buildDepends = with self; [ megaparsec protolude tasty-hunit tasty-th either neat-interpolation tasty-quickcheck quickcheck-instances ];
diff --git a/src/Distribution/Nixpkgs/Nodejs/Cli.hs b/src/Distribution/Nixpkgs/Nodejs/Cli.hs
--- a/src/Distribution/Nixpkgs/Nodejs/Cli.hs
+++ b/src/Distribution/Nixpkgs/Nodejs/Cli.hs
@@ -14,7 +14,7 @@
 import qualified System.Directory as Dir
 
 import qualified Nix.Pretty as NixP
-import Text.PrettyPrint.ANSI.Leijen (putDoc)
+import Data.Text.Prettyprint.Doc.Render.Text (putDoc)
 import qualified Yarn.Lock as YL
 import qualified Yarn.Lock.Types as YLT
 import qualified Yarn.Lock.Helpers as YLH
diff --git a/src/Distribution/Nixpkgs/Nodejs/OptimizedNixOutput.hs b/src/Distribution/Nixpkgs/Nodejs/OptimizedNixOutput.hs
--- a/src/Distribution/Nixpkgs/Nodejs/OptimizedNixOutput.hs
+++ b/src/Distribution/Nixpkgs/Nodejs/OptimizedNixOutput.hs
@@ -78,12 +78,14 @@
 
 -- | Final package reference used in the generated package list.
 data PkgRef
+  -- | reference to another package definition (e.g. @^1.2@ points to @1.2@)
   = PkgRef Text
-    -- ^ reference to another package definition (e.g. @^1.2@ points to @1.2@)
   | PkgDefFile (PkgData (Either Text Registry))
-    -- ^ actual definiton of a file package
+  -- ^ actual definition of a file package
+  | PkgDefFileLocal (PkgData Text)
+  -- ^ actual definition of a local package (tar.gz file relative to nix expression)
   | PkgDefGit  (PkgData Git)
-    -- ^ actual definiton of a git package
+  -- ^ actual definition of a git package
 
 -- | Package definition needed for calling the build function.
 data PkgData a = PkgData
@@ -115,6 +117,7 @@
   , (["registries", "yarn"], "y")
   , (["registries", "npm"], "n")
   , (["nodeFilePackage"], "f")
+  , (["nodeFileLocalPackage"], "l")
   , (["nodeGitPackage"], "g")
   , (["identityRegistry"], "ir")
   , (["scopedName"], "sc")
@@ -164,8 +167,14 @@
         YLT.FileRemote{fileUrl} ->
           PkgDefFile $ pkgDataGeneric $ note fileUrl
             $ recognizeRegistry defName fileUrl
+        YLT.FileLocal{fileLocalPath} ->
+          PkgDefFileLocal $ pkgDataGeneric $ fileLocalPath
         YLT.GitRemote{gitRepoUrl, gitRev} ->
           PkgDefGit $ pkgDataGeneric $ Git gitRepoUrl gitRev
+        YLT.FileRemoteNoIntegrity{..} ->
+          panic "programming error, should have thrown an error in ResolveLockfile"
+        YLT.FileLocalNoIntegrity{..} ->
+          panic "programming error, should have thrown an error in ResolveLockfile"
                  -- we don’t need another ref indirection
                  -- if that’s already the name of our def
       refNames = List.delete defSym $ toList $ NE.nub
@@ -188,6 +197,7 @@
   # We want each package definition to be one line, by putting
   # the boilerplate into these functions for different remotes.
   nodeFilePackage = …
+  nodeFileLocalPackage = …
   nodeGitPackage = …
 
   # an identity function for e.g. git repos or unknown registries
@@ -200,6 +210,7 @@
   s = self;
   ir = identityRegistry;
   f = nodeFilePackage;
+  l = nodeFileLocalPackage;
   g = nodeGitPackage;
   y = registries.yarnpkg;
   sc = scopedName;
@@ -214,6 +225,7 @@
   "babel-core@6.24.1" = f "babel-core" "6.24.1" y "a0e457c58ebdbae575c9f8cd75127e93756435d8" [
     s."accepts@~1.3.3"
   ];
+  "local-package@file:../foo.tgz" = l "local-package" "file:../foo.tgz" ../foo.tgz "thehash" []
 }
 @
 -}
@@ -230,6 +242,7 @@
     ==> N.mkLets
         (  [ "registries" $= N.mkNonRecSet (fmap (mkRegistry . snd) registries)
            , "nodeFilePackage" $= buildPkgFn
+           , "nodeFileLocalPackage" $= buildPkgLocalFn
            , "nodeGitPackage" $= buildPkgGitFn
            , "identityRegistry" $= NA.multiParam ["url", "_", "_"] "url"
            , "scopedName" $=
@@ -265,6 +278,15 @@
         ("fetchurl" @@ N.mkNonRecSet
           [ "url" $= ("registry" @@ "key" @@ "version")
           , inheritStatic ["sha1"] ])
+    -- | Building a 'YLT.FileLocal' package.
+    buildPkgLocalFn :: NExpr
+    buildPkgLocalFn =
+      buildPkgFnGeneric ["path", "sha1"]
+        ("builtins.path" @@ N.mkNonRecSet
+          [ inheritStatic ["path"]
+          -- TODO: use the sha1 here! (does builtins.path only take sha256?)
+          -- , "sha256" $= "sha1"
+          ])
     -- | Building a 'YLT.GitRemote' package.
     buildPkgGitFn :: NExpr
     buildPkgGitFn =
@@ -272,16 +294,7 @@
         ("fetchgit" @@ N.mkNonRecSet
           [ inheritStatic ["url", "rev", "sha256"] ])
 
-    mkDefGeneric :: PkgData a -> NSym -> [NExpr] -> NExpr
-    mkDefGeneric PkgData{..} buildFnSym additionalArguments =
-      foldl' (@@) (shorten [buildFnSym])
-        $ [ case pkgDataName of
-              YLT.SimplePackageKey n -> N.mkStr n
-              YLT.ScopedPackageKey s n -> "sc" @@ N.mkStr s @@ N.mkStr n
-          , N.mkStr pkgDataVersion ]
-          <> additionalArguments <>
-          [ N.mkList $ map (N.mkSym selfSym !!.) pkgDataDependencies ]
-
+    -- | Create a package definition.
     mkPkg :: (Text, PkgRef) -> N.Binding NExpr
     mkPkg (key, pkgRef) = key $$= case pkgRef of
       PkgRef t -> N.mkSym selfSym !!. t
@@ -291,9 +304,22 @@
                    (\reg -> shorten ["registries", registrySym reg])
                    pkgDataUpstream
           , N.mkStr pkgDataHashSum ]
+      PkgDefFileLocal pd@PkgData{pkgDataUpstream = path, pkgDataHashSum} ->
+        mkDefGeneric pd "nodeFileLocalPackage" [ N.mkPath False (toS path), N.mkStr pkgDataHashSum ]
       PkgDefGit pd@PkgData{pkgDataUpstream = Git{..}, pkgDataHashSum} ->
         mkDefGeneric pd "nodeGitPackage"
           [ N.mkStr gitUrl, N.mkStr gitRev, N.mkStr pkgDataHashSum ]
+
+    -- | The common parts of creating a package definition.
+    mkDefGeneric :: PkgData a -> NSym -> [NExpr] -> NExpr
+    mkDefGeneric PkgData{..} buildFnSym additionalArguments =
+      foldl' (@@) (shorten [buildFnSym])
+        $ [ case pkgDataName of
+              YLT.SimplePackageKey n -> N.mkStr n
+              YLT.ScopedPackageKey s n -> "sc" @@ N.mkStr s @@ N.mkStr n
+          , N.mkStr pkgDataVersion ]
+          <> additionalArguments <>
+          [ N.mkList $ map (N.mkSym selfSym !!.) pkgDataDependencies ]
 
     selfSym :: Text
     selfSym = "s"
diff --git a/src/Distribution/Nixpkgs/Nodejs/ResolveLockfile.hs b/src/Distribution/Nixpkgs/Nodejs/ResolveLockfile.hs
--- a/src/Distribution/Nixpkgs/Nodejs/ResolveLockfile.hs
+++ b/src/Distribution/Nixpkgs/Nodejs/ResolveLockfile.hs
@@ -59,7 +59,16 @@
     resolve :: YLT.Package -> E.ExceptT Text IO (Resolved YLT.Package)
     resolve pkg = case YLT.remote pkg of
       YLT.FileRemote{..} -> pure $ r fileSha1
+      YLT.FileLocal{..}  -> pure $ r fileLocalSha1
       YLT.GitRemote{..}  -> r <$> fetchFromGit gitRepoUrl gitRev
+      YLT.FileRemoteNoIntegrity{..} -> E.throwE
+        $ "The remote "
+        <> fileNoIntegrityUrl
+        <> " does not specify a sha1 hash in the yarn.lock file, which we don’t support (yet)"
+      YLT.FileLocalNoIntegrity{..} -> E.throwE
+        $ "The local file "
+        <> fileLocalNoIntegrityPath
+        <> " does not specify a sha1 hash in the yarn.lock file, which we don’t support (yet)"
       where
         r sha = Resolved { hashSum = sha, resolved = pkg }
 
diff --git a/yarn2nix.cabal b/yarn2nix.cabal
--- a/yarn2nix.cabal
+++ b/yarn2nix.cabal
@@ -1,11 +1,13 @@
--- This file has been generated from package.yaml by hpack version 0.27.0.
+cabal-version: 1.12
+
+-- This file has been generated from package.yaml by hpack version 0.33.0.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 9f5e62ecebb812a5457199df157d56a8529dd64b80a8ea3c7fbbbf22d86627f3
+-- hash: 5daa56420b918ef3cbd08426830e2e6fd2caf9897d7b21ec8141f33a81148fd3
 
 name:           yarn2nix
-version:        0.7.0
+version:        0.8.0
 synopsis:       Convert yarn.lock files to nix expressions
 description:    Convert @yarn.lock@ files to nix expressions. See @yarn2nix@ executable. Contains a nix library to call the generated nix files in @nix-lib/@. Library functions and module names might be restructured in the future.
 category:       Distribution, Nix
@@ -16,17 +18,15 @@
 license:        MIT
 license-file:   LICENSE
 build-type:     Simple
-cabal-version:  >= 1.10
-
 extra-source-files:
-    default.nix
     LICENSE
+    README.md
+    yarn2nix.nix
+    default.nix
+    shell.nix
     nix-lib/buildNodePackage.nix
     nix-lib/default.nix
     nix-lib/old-version-dependencies.nix
-    README.md
-    shell.nix
-    yarn2nix.nix
 
 source-repository head
   type: git
@@ -47,8 +47,7 @@
       src
   ghc-options: -Wall
   build-depends:
-      aeson >=1.0 && <1.3
-    , ansi-wl-pprint ==0.6.*
+      aeson >=1.0 && <1.5
     , async-pool ==0.9.*
     , base ==4.*
     , bytestring ==0.10.*
@@ -56,17 +55,18 @@
     , data-fix ==0.0.7 || ==0.2.0
     , directory ==1.3.*
     , filepath ==1.4.*
-    , hnix ==0.5.*
+    , hnix ==0.6.*
     , mtl ==2.2.*
+    , prettyprinter ==1.2.*
     , process >=1.4
     , protolude ==0.2.*
     , regex-tdfa ==1.2.*
     , regex-tdfa-text ==1.0.0.*
-    , stm ==2.4.*
+    , stm >2.4.0 && <2.6.0.0
     , text ==1.2.*
     , transformers ==0.5.*
     , unordered-containers ==0.2.*
-    , yarn-lock ==0.5.*
+    , yarn-lock ==0.6.*
   default-language: Haskell2010
 
 executable node-package-tool
@@ -75,8 +75,7 @@
       Paths_yarn2nix
   ghc-options: -Wall
   build-depends:
-      aeson >=1.0 && <1.3
-    , ansi-wl-pprint ==0.6.*
+      aeson >=1.0 && <1.5
     , async-pool ==0.9.*
     , base ==4.*
     , bytestring ==0.10.*
@@ -84,19 +83,20 @@
     , data-fix ==0.0.7 || ==0.2.0
     , directory ==1.3.*
     , filepath ==1.4.*
-    , hnix ==0.5.*
+    , hnix ==0.6.*
     , mtl ==2.2.*
     , optparse-applicative >=0.13 && <0.15
+    , prettyprinter ==1.2.*
     , process >=1.4
     , protolude ==0.2.*
     , regex-tdfa ==1.2.*
     , regex-tdfa-text ==1.0.0.*
-    , stm ==2.4.*
+    , stm >2.4.0 && <2.6.0.0
     , text ==1.2.*
     , transformers ==0.5.*
     , unix ==2.7.*
     , unordered-containers ==0.2.*
-    , yarn-lock ==0.5.*
+    , yarn-lock ==0.6.*
     , yarn2nix
   default-language: Haskell2010
 
@@ -106,8 +106,7 @@
       Paths_yarn2nix
   ghc-options: -Wall
   build-depends:
-      aeson >=1.0 && <1.3
-    , ansi-wl-pprint ==0.6.*
+      aeson >=1.0 && <1.5
     , async-pool ==0.9.*
     , base ==4.*
     , bytestring ==0.10.*
@@ -115,17 +114,18 @@
     , data-fix ==0.0.7 || ==0.2.0
     , directory ==1.3.*
     , filepath ==1.4.*
-    , hnix ==0.5.*
+    , hnix ==0.6.*
     , mtl ==2.2.*
+    , prettyprinter ==1.2.*
     , process >=1.4
     , protolude ==0.2.*
     , regex-tdfa ==1.2.*
     , regex-tdfa-text ==1.0.0.*
-    , stm ==2.4.*
+    , stm >2.4.0 && <2.6.0.0
     , text ==1.2.*
     , transformers ==0.5.*
     , unordered-containers ==0.2.*
-    , yarn-lock ==0.5.*
+    , yarn-lock ==0.6.*
     , yarn2nix
   default-language: Haskell2010
 
@@ -139,8 +139,7 @@
       tests
   ghc-options: -Wall
   build-depends:
-      aeson >=1.0 && <1.3
-    , ansi-wl-pprint ==0.6.*
+      aeson >=1.0 && <1.5
     , async-pool ==0.9.*
     , base ==4.*
     , bytestring ==0.10.*
@@ -148,21 +147,22 @@
     , data-fix ==0.0.7 || ==0.2.0
     , directory ==1.3.*
     , filepath ==1.4.*
-    , hnix ==0.5.*
+    , hnix ==0.6.*
     , mtl ==2.2.*
     , neat-interpolation ==0.3.*
+    , prettyprinter ==1.2.*
     , process >=1.4
     , protolude ==0.2.*
     , regex-tdfa ==1.2.*
     , regex-tdfa-text ==1.0.0.*
-    , stm ==2.4.*
+    , stm >2.4.0 && <2.6.0.0
     , tasty >=0.11 && <1.2
     , tasty-hunit >=0.9 && <0.11
-    , tasty-quickcheck ==0.8.* || ==0.9.*
+    , tasty-quickcheck >=0.8 && <0.11
     , tasty-th ==0.1.7.*
     , text ==1.2.*
     , transformers ==0.5.*
     , unordered-containers ==0.2.*
-    , yarn-lock ==0.5.*
+    , yarn-lock ==0.6.*
     , yarn2nix
   default-language: Haskell2010