diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# Version [0.1.2.0](https://github.com/expipiplus1/update-nix-fetchgit/compare/0.1.1.0...0.1.2.0)
+
+* Additions
+  * Support updating `fetchFromGitLab`
+  * Support updating `fetchgit` and `fetchgitPrivate
+
 # Version [0.1.1.0](https://github.com/expipiplus1/update-nix-fetchgit/compare/0.1.0.0...0.1.1.0)
 
 * Changelog started. Previous release was `0.1.0.0`.
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@
 When you run `update-nix-fetchgit` on a file, it will:
 
 - Read the file and parse it as a Nix expression.
-- Find all Git fetches (calls to `fetchgit`, `fetchgitPrivate`, or `fetchFromGitHub`).
+- Find all Git fetches (calls to `fetchgit`, `fetchgitPrivate`, `fetchFromGitHub` or `fetchFromGitLab`).
 - Run [`nix-prefetch-git`](https://github.com/NixOS/nixpkgs/blob/master/pkgs/build-support/fetchgit/nix-prefetch-git) to get information about the latest HEAD commit of each repository.
 - Update the corresponding rev, sha256, and version attributes for each repository.
 - Overwrite the original input file.
diff --git a/src/Update/Nix/FetchGit.hs b/src/Update/Nix/FetchGit.hs
--- a/src/Update/Nix/FetchGit.hs
+++ b/src/Update/Nix/FetchGit.hs
@@ -73,11 +73,21 @@
     || extractFuncName function == Just "fetchgitPrivate"
     -> FetchNode <$> extractFetchGitArgs bindings
 
-  -- Similarly, record calls to fetchFromGitHub.
+  -- Similarly for builtins.fetchGit which needs special handling.
   AnnE _ (NBinary NApp function (AnnE _ (NSet _rec bindings)))
+    | extractFuncName function == Just "fetchGit"
+    -> FetchNode <$> extractFetchGitBuiltinArgs bindings
+
+  -- Also record calls to fetchFromGitHub.
+  AnnE _ (NBinary NApp function (AnnE _ (NSet _rec bindings)))
     | extractFuncName function == Just "fetchFromGitHub"
     -> FetchNode <$> extractFetchFromGitHubArgs bindings
 
+  -- And to fetchFromGitLab.
+  AnnE _ (NBinary NApp function (AnnE _ (NSet _rec bindings)))
+    | extractFuncName function == Just "fetchFromGitLab"
+    -> FetchNode <$> extractFetchFromGitLabArgs bindings
+
   -- If it is an attribute set, find any attributes in it that we
   -- might want to update.
   AnnE _ (NSet _rec bindings)
@@ -91,16 +101,32 @@
 extractFetchGitArgs bindings =
     FetchGitArgs <$> (URL <$> (exprText =<< extractAttr "url" bindings))
                  <*> extractAttr "rev" bindings
-                 <*> extractAttr "sha256" bindings
+                 <*> (Just <$> extractAttr "sha256" bindings)
 
+-- | Extract a 'FetchGitArgs' from the attrset being passed to builtins.fetchGit,
+--   unlike all the other functions it does not include a sha256 field.
+extractFetchGitBuiltinArgs :: [Binding NExprLoc] -> Either Warning FetchGitArgs
+extractFetchGitBuiltinArgs bindings =
+    FetchGitArgs <$> (URL <$> (exprText =<< extractAttr "url" bindings))
+                 <*> extractAttr "rev" bindings
+                 <*> pure Nothing
+
 -- | Extract a 'FetchGitArgs' from the attrset being passed to fetchFromGitHub.
 extractFetchFromGitHubArgs :: [Binding NExprLoc] -> Either Warning FetchGitArgs
 extractFetchFromGitHubArgs bindings =
     FetchGitArgs <$> (GitHub <$> (exprText =<< extractAttr "owner" bindings)
                              <*> (exprText =<< extractAttr "repo" bindings))
                  <*> extractAttr "rev" bindings
-                 <*> extractAttr "sha256" bindings
+                 <*> (Just <$> extractAttr "sha256" bindings)
 
+-- | Extract a 'FetchGitArgs' from the attrset being passed to fetchFromGitLab.
+extractFetchFromGitLabArgs :: [Binding NExprLoc] -> Either Warning FetchGitArgs
+extractFetchFromGitLabArgs bindings =
+    FetchGitArgs <$> (GitLab <$> (exprText =<< extractAttr "owner" bindings)
+                             <*> (exprText =<< extractAttr "repo" bindings))
+                 <*> extractAttr "rev" bindings
+                 <*> (Just <$> extractAttr "sha256" bindings)
+
 --------------------------------------------------------------------------------
 -- Getting updated information from the internet.
 --------------------------------------------------------------------------------
@@ -119,11 +145,11 @@
 fetchTreeToSpanUpdates node@(Node _ cs) =
   concatMap fetchTreeToSpanUpdates cs ++
   toList (maybeUpdateVersion node)
-fetchTreeToSpanUpdates (FetchNode f) = [revUpdate, sha256Update]
+fetchTreeToSpanUpdates (FetchNode f) = catMaybes [Just revUpdate, sha256Update]
   where revUpdate = SpanUpdate (exprSpan (revExpr args))
                                (quoteString (latestRev f))
-        sha256Update = SpanUpdate (exprSpan (sha256Expr args))
-                                  (quoteString (latestSha256 f))
+        sha256Update = SpanUpdate <$> (exprSpan <$> sha256Expr args)
+                                  <*> Just (quoteString (latestSha256 f))
         args = originalInfo f
 
 -- Given a node of the fetch tree which might contain a version
diff --git a/src/Update/Nix/FetchGit/Types.hs b/src/Update/Nix/FetchGit/Types.hs
--- a/src/Update/Nix/FetchGit/Types.hs
+++ b/src/Update/Nix/FetchGit/Types.hs
@@ -24,11 +24,12 @@
                          | FetchNode fetchInfo
   deriving (Show, Data, Functor, Foldable, Traversable)
 
--- | Represents the arugments to a call to fetchgit or fetchFromGitHub
---   as parsed from a .nix file.
+-- | Represents the arguments to a call to fetchgit, fetchFromGitHub
+--   or fetchFromGitLab as parsed from a .nix file.
+--   sha256Expr will be empty on calls to builtins.fetchGit.
 data FetchGitArgs = FetchGitArgs { repoLocation :: RepoLocation
                                  , revExpr      :: NExprLoc
-                                 , sha256Expr   :: NExprLoc
+                                 , sha256Expr   :: Maybe NExprLoc
                                  }
   deriving (Show, Data)
 
@@ -44,6 +45,9 @@
 -- | A repo is either specified by URL or by Github owner/repo.
 data RepoLocation = URL Text
                   | GitHub { owner :: Text
+                           , repo  :: Text
+                           }
+                  | GitLab { owner :: Text
                            , repo  :: Text
                            }
   deriving (Show, Data)
diff --git a/src/Update/Nix/FetchGit/Utils.hs b/src/Update/Nix/FetchGit/Utils.hs
--- a/src/Update/Nix/FetchGit/Utils.hs
+++ b/src/Update/Nix/FetchGit/Utils.hs
@@ -48,6 +48,7 @@
 extractUrlString = \case
   URL u -> u
   GitHub o r -> "https://github.com/" <> o <> "/" <> r <> ".git"
+  GitLab o r -> "https://gitlab.com/" <> o <> "/" <> r <> ".git"
 
 -- Add double quotes around a string so it can be inserted into a Nix
 -- file as a string literal.
diff --git a/update-nix-fetchgit.cabal b/update-nix-fetchgit.cabal
--- a/update-nix-fetchgit.cabal
+++ b/update-nix-fetchgit.cabal
@@ -1,5 +1,5 @@
 name:                update-nix-fetchgit
-version:             0.1.1.0
+version:             0.1.2.0
 synopsis:            A program to update fetchgit values in Nix expressions
 description:         This command-line utility is meant to be used by people maintaining Nix expressions that fetch files from Git repositories.
                      It automates the process of keeping such expressions up-to-date with the latest upstream sources.
@@ -29,7 +29,6 @@
                      , aeson >= 0.9
                      , async >= 2.1
                      , bytestring >= 0.10
-                     , data-fix >= 0.0
                      , errors >= 2.1
                      , hnix >= 0.8
                      , prettyprinter
@@ -37,7 +36,6 @@
                      , text >= 1.2
                      , time >= 1.5
                      , transformers >= 0.4
-                     , trifecta >= 1.6
                      , uniplate >= 1.6
                      , utf8-string >= 1.0
   default-language:    Haskell2010