3 files changed, 28 insertions, 1 deletions

diff --git a/src/libcmd/command.hh b/src/libcmd/command.hh
index b6d554aab..49c7b4f9b 100644
--- a/src/libcmd/command.hh
+++ b/src/libcmd/command.hh
@@ -128,6 +128,8 @@ struct InstallablesCommand : virtual Args, SourceExprCommand
 
     virtual bool useDefaultInstallables() { return true; }
 
+    bool readFromStdIn;
+
     std::vector<std::string> getFlakesForCompletion() override;
 
 protected:
diff --git a/src/libcmd/installables.cc b/src/libcmd/installables.cc
index 90f001902..7d444aac0 100644
--- a/src/libcmd/installables.cc
+++ b/src/libcmd/installables.cc
@@ -694,6 +694,13 @@ StorePathSet Installable::toDerivations(
 
 InstallablesCommand::InstallablesCommand()
 {
+
+    addFlag({
+        .longName = "stdin",
+        .description = "Read installables from the standard input.",
+        .handler = {&readFromStdIn, true}
+    });
+
     expectArgs({
         .label = "installables",
         .handler = {&_installables},
@@ -710,10 +717,18 @@ void InstallablesCommand::prepare()
 
 Installables InstallablesCommand::load()
 {
-    if (_installables.empty() && useDefaultInstallables())
+    if (_installables.empty() && useDefaultInstallables() && !readFromStdIn)
         // FIXME: commands like "nix profile install" should not have a
         // default, probably.
         _installables.push_back(".");
+
+    if (readFromStdIn && !isatty(STDIN_FILENO)) {
+        std::string word;
+        while (std::cin >> word) {
+            _installables.emplace_back(std::move(word));
+        }
+    }
+
     return parseInstallables(getStore(), _installables);
 }
 
diff --git a/src/nix-store/nix-store.cc b/src/nix-store/nix-store.cc
index 3bbefedbe..d4218550a 100644
--- a/src/nix-store/nix-store.cc
+++ b/src/nix-store/nix-store.cc
@@ -1020,6 +1020,7 @@ static int main_nix_store(int argc, char * * argv)
     {
         Strings opFlags, opArgs;
         Operation op = 0;
+        bool readFromStdIn;
 
         parseCmdLine(argc, argv, [&](Strings::iterator & arg, const Strings::iterator & end) {
             Operation oldOp = op;
@@ -1078,6 +1079,8 @@ static int main_nix_store(int argc, char * * argv)
                 op = opGenerateBinaryCacheKey;
             else if (*arg == "--add-root")
                 gcRoot = absPath(getArg(*arg, arg, end));
+            else if (*arg == "--stdin" && !isatty(STDIN_FILENO))
+                readFromStdIn = true;
             else if (*arg == "--indirect")
                 ;
             else if (*arg == "--no-output")
@@ -1090,6 +1093,13 @@ static int main_nix_store(int argc, char * * argv)
             else
                 opArgs.push_back(*arg);
 
+            if (readFromStdIn && op != opImport && op != opRestore && op != opServe) {
+                 std::string word;
+                 while (std::cin >> word) {
+                       opArgs.emplace_back(std::move(word));
+                 };
+            }
+
             if (oldOp && oldOp != op)
                 throw UsageError("only one operation may be specified");