Merge branch 'master' into lto

13 files changed, 205 insertions, 90 deletions

diff --git a/src/nix/app.cc b/src/nix/app.cc
index 95ac1cf5c..821964f86 100644
--- a/src/nix/app.cc
+++ b/src/nix/app.cc
@@ -66,7 +66,7 @@ UnresolvedApp Installable::toApp(EvalState & state)
 
     auto type = cursor->getAttr("type")->getString();
 
-    std::string expected = !attrPath.empty() && attrPath[0] == "apps" ? "app" : "derivation";
+    std::string expected = !attrPath.empty() && state.symbols[attrPath[0]] == "apps" ? "app" : "derivation";
     if (type != expected)
         throw Error("attribute '%s' should have type '%s'", cursor->getAttrPathStr(), expected);
 
@@ -85,11 +85,11 @@ UnresolvedApp Installable::toApp(EvalState & state)
 
     else if (type == "derivation") {
         auto drvPath = cursor->forceDerivation();
-        auto outPath = cursor->getAttr("outPath")->getString();
-        auto outputName = cursor->getAttr("outputName")->getString();
-        auto name = cursor->getAttr("name")->getString();
+        auto outPath = cursor->getAttr(state.sOutPath)->getString();
+        auto outputName = cursor->getAttr(state.sOutputName)->getString();
+        auto name = cursor->getAttr(state.sName)->getString();
         auto aPname = cursor->maybeGetAttr("pname");
-        auto aMeta = cursor->maybeGetAttr("meta");
+        auto aMeta = cursor->maybeGetAttr(state.sMeta);
         auto aMainProgram = aMeta ? aMeta->maybeGetAttr("mainProgram") : nullptr;
         auto mainProgram =
             aMainProgram
diff --git a/src/nix/bundle.cc b/src/nix/bundle.cc
index 2421adf4e..2e48e4c74 100644
--- a/src/nix/bundle.cc
+++ b/src/nix/bundle.cc
@@ -75,10 +75,10 @@ struct CmdBundle : InstallableCommand
 
         auto val = installable->toValue(*evalState).first;
 
-        auto [bundlerFlakeRef, bundlerName] = parseFlakeRefWithFragment(bundler, absPath("."));
+        auto [bundlerFlakeRef, bundlerName, outputsSpec] = parseFlakeRefWithFragmentAndOutputsSpec(bundler, absPath("."));
         const flake::LockFlags lockFlags{ .writeLockFile = false };
         InstallableFlake bundler{this,
-            evalState, std::move(bundlerFlakeRef), bundlerName,
+            evalState, std::move(bundlerFlakeRef), bundlerName, outputsSpec,
             {"bundlers." + settings.thisSystem.get() + ".default",
              "defaultBundler." + settings.thisSystem.get()
             },
diff --git a/src/nix/develop.cc b/src/nix/develop.cc
index 7fc74d34e..2a3fc0213 100644
--- a/src/nix/develop.cc
+++ b/src/nix/develop.cc
@@ -18,6 +18,9 @@ struct DevelopSettings : Config
     Setting<std::string> bashPrompt{this, "", "bash-prompt",
         "The bash prompt (`PS1`) in `nix develop` shells."};
 
+    Setting<std::string> bashPromptPrefix{this, "", "bash-prompt-prefix",
+        "Prefix prepended to the `PS1` environment variable in `nix develop` shells."};
+
     Setting<std::string> bashPromptSuffix{this, "", "bash-prompt-suffix",
         "Suffix appended to the `PS1` environment variable in `nix develop` shells."};
 };
@@ -482,6 +485,9 @@ struct CmdDevelop : Common, MixEnvironment
             if (developSettings.bashPrompt != "")
                 script += fmt("[ -n \"$PS1\" ] && PS1=%s;\n",
                     shellEscape(developSettings.bashPrompt.get()));
+            if (developSettings.bashPromptPrefix != "")
+                script += fmt("[ -n \"$PS1\" ] && PS1=%s\"$PS1\";\n",
+                    shellEscape(developSettings.bashPromptPrefix.get()));
             if (developSettings.bashPromptSuffix != "")
                 script += fmt("[ -n \"$PS1\" ] && PS1+=%s;\n",
                     shellEscape(developSettings.bashPromptSuffix.get()));
@@ -507,13 +513,25 @@ struct CmdDevelop : Common, MixEnvironment
                 state,
                 installable->nixpkgsFlakeRef(),
                 "bashInteractive",
+                DefaultOutputs(),
                 Strings{},
                 Strings{"legacyPackages." + settings.thisSystem.get() + "."},
                 nixpkgsLockFlags);
 
-            shell = store->printStorePath(
-                Installable::toStorePath(getEvalStore(), store, Realise::Outputs, OperateOn::Output, bashInstallable))
-                + "/bin/bash";
+            bool found = false;
+
+            for (auto & path : Installable::toStorePaths(getEvalStore(), store, Realise::Outputs, OperateOn::Output, {bashInstallable})) {
+                auto s = store->printStorePath(path) + "/bin/bash";
+                if (pathExists(s)) {
+                    shell = s;
+                    found = true;
+                    break;
+                }
+            }
+
+            if (!found)
+                throw Error("package 'nixpkgs#bashInteractive' does not provide a 'bin/bash'");
+
         } catch (Error &) {
             ignoreException();
         }
diff --git a/src/nix/develop.md b/src/nix/develop.md
index 8bcff66c9..e036ec6b9 100644
--- a/src/nix/develop.md
+++ b/src/nix/develop.md
@@ -80,8 +80,8 @@ initialised by `stdenv` and exits. This build environment can be
 recorded into a profile using `--profile`.
 
 The prompt used by the `bash` shell can be customised by setting the
-`bash-prompt` and `bash-prompt-suffix` settings in `nix.conf` or in
-the flake's `nixConfig` attribute.
+`bash-prompt`, `bash-prompt-prefix`, and `bash-prompt-suffix` settings in
+`nix.conf` or in the flake's `nixConfig` attribute.
 
 # Flake output attributes
 
diff --git a/src/nix/flake.cc b/src/nix/flake.cc
index c8d8461e4..8370b8dcf 100644
--- a/src/nix/flake.cc
+++ b/src/nix/flake.cc
@@ -311,7 +311,7 @@ struct CmdFlakeCheck : FlakeCommand
             return state->positions[p];
         };
 
-        auto argHasName = [&] (SymbolIdx arg, std::string_view expected) {
+        auto argHasName = [&] (Symbol arg, std::string_view expected) {
             std::string_view name = state->symbols[arg];
             return
                 name == expected
@@ -509,7 +509,7 @@ struct CmdFlakeCheck : FlakeCommand
 
                         std::string_view replacement =
                             name == "defaultPackage" ? "packages.<system>.default" :
-                            name == "defaultApps" ? "apps.<system>.default" :
+                            name == "defaultApp" ? "apps.<system>.default" :
                             name == "defaultTemplate" ? "templates.default" :
                             name == "defaultBundler" ? "bundlers.<system>.default" :
                             name == "overlay" ? "overlays.default" :
@@ -724,7 +724,7 @@ struct CmdFlakeInitCommon : virtual Args, EvalCommand
         auto [templateFlakeRef, templateName] = parseFlakeRefWithFragment(templateUrl, absPath("."));
 
         auto installable = InstallableFlake(nullptr,
-            evalState, std::move(templateFlakeRef), templateName,
+            evalState, std::move(templateFlakeRef), templateName, DefaultOutputs(),
             defaultTemplateAttrPaths,
             defaultTemplateAttrPathsPrefixes,
             lockFlags);
@@ -986,8 +986,11 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
         {
             auto j = nlohmann::json::object();
 
+            auto attrPathS = state->symbols.resolve(attrPath);
+
             Activity act(*logger, lvlInfo, actUnknown,
-                fmt("evaluating '%s'", concatStringsSep(".", attrPath)));
+                fmt("evaluating '%s'", concatStringsSep(".", attrPathS)));
+
             try {
                 auto recurse = [&]()
                 {
@@ -995,24 +998,25 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
                         logger->cout("%s", headerPrefix);
                     auto attrs = visitor.getAttrs();
                     for (const auto & [i, attr] : enumerate(attrs)) {
+                        const auto & attrName = state->symbols[attr];
                         bool last = i + 1 == attrs.size();
-                        auto visitor2 = visitor.getAttr(attr);
+                        auto visitor2 = visitor.getAttr(attrName);
                         auto attrPath2(attrPath);
                         attrPath2.push_back(attr);
                         auto j2 = visit(*visitor2, attrPath2,
-                            fmt(ANSI_GREEN "%s%s" ANSI_NORMAL ANSI_BOLD "%s" ANSI_NORMAL, nextPrefix, last ? treeLast : treeConn, attr),
+                            fmt(ANSI_GREEN "%s%s" ANSI_NORMAL ANSI_BOLD "%s" ANSI_NORMAL, nextPrefix, last ? treeLast : treeConn, attrName),
                             nextPrefix + (last ? treeNull : treeLine));
-                        if (json) j.emplace(attr, std::move(j2));
+                        if (json) j.emplace(attrName, std::move(j2));
                     }
                 };
 
                 auto showDerivation = [&]()
                 {
-                    auto name = visitor.getAttr("name")->getString();
+                    auto name = visitor.getAttr(state->sName)->getString();
                     if (json) {
                         std::optional<std::string> description;
-                        if (auto aMeta = visitor.maybeGetAttr("meta")) {
-                            if (auto aDescription = aMeta->maybeGetAttr("description"))
+                        if (auto aMeta = visitor.maybeGetAttr(state->sMeta)) {
+                            if (auto aDescription = aMeta->maybeGetAttr(state->sDescription))
                                 description = aDescription->getString();
                         }
                         j.emplace("type", "derivation");
@@ -1022,10 +1026,10 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
                     } else {
                         logger->cout("%s: %s '%s'",
                             headerPrefix,
-                            attrPath.size() == 2 && attrPath[0] == "devShell" ? "development environment" :
-                            attrPath.size() >= 2 && attrPath[0] == "devShells" ? "development environment" :
-                            attrPath.size() == 3 && attrPath[0] == "checks" ? "derivation" :
-                            attrPath.size() >= 1 && attrPath[0] == "hydraJobs" ? "derivation" :
+                            attrPath.size() == 2 && attrPathS[0] == "devShell" ? "development environment" :
+                            attrPath.size() >= 2 && attrPathS[0] == "devShells" ? "development environment" :
+                            attrPath.size() == 3 && attrPathS[0] == "checks" ? "derivation" :
+                            attrPath.size() >= 1 && attrPathS[0] == "hydraJobs" ? "derivation" :
                             "package",
                             name);
                     }
@@ -1033,27 +1037,27 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
 
                 if (attrPath.size() == 0
                     || (attrPath.size() == 1 && (
-                            attrPath[0] == "defaultPackage"
-                            || attrPath[0] == "devShell"
-                            || attrPath[0] == "formatter"
-                            || attrPath[0] == "nixosConfigurations"
-                            || attrPath[0] == "nixosModules"
-                            || attrPath[0] == "defaultApp"
-                            || attrPath[0] == "templates"
-                            || attrPath[0] == "overlays"))
+                            attrPathS[0] == "defaultPackage"
+                            || attrPathS[0] == "devShell"
+                            || attrPathS[0] == "formatter"
+                            || attrPathS[0] == "nixosConfigurations"
+                            || attrPathS[0] == "nixosModules"
+                            || attrPathS[0] == "defaultApp"
+                            || attrPathS[0] == "templates"
+                            || attrPathS[0] == "overlays"))
                     || ((attrPath.size() == 1 || attrPath.size() == 2)
-                        && (attrPath[0] == "checks"
-                            || attrPath[0] == "packages"
-                            || attrPath[0] == "devShells"
-                            || attrPath[0] == "apps"))
+                        && (attrPathS[0] == "checks"
+                            || attrPathS[0] == "packages"
+                            || attrPathS[0] == "devShells"
+                            || attrPathS[0] == "apps"))
                     )
                 {
                     recurse();
                 }
 
                 else if (
-                    (attrPath.size() == 2 && (attrPath[0] == "defaultPackage" || attrPath[0] == "devShell" || attrPath[0] == "formatter"))
-                    || (attrPath.size() == 3 && (attrPath[0] == "checks" || attrPath[0] == "packages" || attrPath[0] == "devShells"))
+                    (attrPath.size() == 2 && (attrPathS[0] == "defaultPackage" || attrPathS[0] == "devShell" || attrPathS[0] == "formatter"))
+                    || (attrPath.size() == 3 && (attrPathS[0] == "checks" || attrPathS[0] == "packages" || attrPathS[0] == "devShells"))
                     )
                 {
                     if (visitor.isDerivation())
@@ -1062,19 +1066,23 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
                         throw Error("expected a derivation");
                 }
 
-                else if (attrPath.size() > 0 && attrPath[0] == "hydraJobs") {
+                else if (attrPath.size() > 0 && attrPathS[0] == "hydraJobs") {
                     if (visitor.isDerivation())
                         showDerivation();
                     else
                         recurse();
                 }
 
-                else if (attrPath.size() > 0 && attrPath[0] == "legacyPackages") {
+                else if (attrPath.size() > 0 && attrPathS[0] == "legacyPackages") {
                     if (attrPath.size() == 1)
                         recurse();
-                    else if (!showLegacy)
-                        logger->warn(fmt("%s: " ANSI_WARNING "omitted" ANSI_NORMAL " (use '--legacy' to show)", headerPrefix));
-                    else {
+                    else if (!showLegacy){
+                        if (!json)
+                            logger->cout(fmt("%s " ANSI_WARNING "omitted" ANSI_NORMAL " (use '--legacy' to show)", headerPrefix));
+                        else {
+                            logger->warn(fmt("%s omitted (use '--legacy' to show)", concatStringsSep(".", attrPathS)));
+                        }
+                    } else {
                         if (visitor.isDerivation())
                             showDerivation();
                         else if (attrPath.size() <= 2)
@@ -1084,8 +1092,8 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
                 }
 
                 else if (
-                    (attrPath.size() == 2 && attrPath[0] == "defaultApp") ||
-                    (attrPath.size() == 3 && attrPath[0] == "apps"))
+                    (attrPath.size() == 2 && attrPathS[0] == "defaultApp") ||
+                    (attrPath.size() == 3 && attrPathS[0] == "apps"))
                 {
                     auto aType = visitor.maybeGetAttr("type");
                     if (!aType || aType->getString() != "app")
@@ -1098,8 +1106,8 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
                 }
 
                 else if (
-                    (attrPath.size() == 1 && attrPath[0] == "defaultTemplate") ||
-                    (attrPath.size() == 2 && attrPath[0] == "templates"))
+                    (attrPath.size() == 1 && attrPathS[0] == "defaultTemplate") ||
+                    (attrPath.size() == 2 && attrPathS[0] == "templates"))
                 {
                     auto description = visitor.getAttr("description")->getString();
                     if (json) {
@@ -1112,11 +1120,11 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
 
                 else {
                     auto [type, description] =
-                        (attrPath.size() == 1 && attrPath[0] == "overlay")
-                        || (attrPath.size() == 2 && attrPath[0] == "overlays") ? std::make_pair("nixpkgs-overlay", "Nixpkgs overlay") :
-                        attrPath.size() == 2 && attrPath[0] == "nixosConfigurations" ? std::make_pair("nixos-configuration", "NixOS configuration") :
-                        (attrPath.size() == 1 && attrPath[0] == "nixosModule")
-                        || (attrPath.size() == 2 && attrPath[0] == "nixosModules") ? std::make_pair("nixos-module", "NixOS module") :
+                        (attrPath.size() == 1 && attrPathS[0] == "overlay")
+                        || (attrPath.size() == 2 && attrPathS[0] == "overlays") ? std::make_pair("nixpkgs-overlay", "Nixpkgs overlay") :
+                        attrPath.size() == 2 && attrPathS[0] == "nixosConfigurations" ? std::make_pair("nixos-configuration", "NixOS configuration") :
+                        (attrPath.size() == 1 && attrPathS[0] == "nixosModule")
+                        || (attrPath.size() == 2 && attrPathS[0] == "nixosModules") ? std::make_pair("nixos-module", "NixOS module") :
                         std::make_pair("unknown", "unknown");
                     if (json) {
                         j.emplace("type", type);
@@ -1125,7 +1133,7 @@ struct CmdFlakeShow : FlakeCommand, MixJSON
                     }
                 }
             } catch (EvalError & e) {
-                if (!(attrPath.size() > 0 && attrPath[0] == "legacyPackages"))
+                if (!(attrPath.size() > 0 && attrPathS[0] == "legacyPackages"))
                     throw;
             }
 
diff --git a/src/nix/flake.md b/src/nix/flake.md
index 7d179a6c4..aa3f9f303 100644
--- a/src/nix/flake.md
+++ b/src/nix/flake.md
@@ -153,7 +153,7 @@ Currently the `type` attribute can be one of the following:
   git(+http|+https|+ssh|+git|+file|):(//<server>)?<path>(\?<params>)?
   ```
 
-  The `ref` attribute defaults to `master`.
+  The `ref` attribute defaults to resolving the `HEAD` reference.
 
   The `rev` attribute must denote a commit that exists in the branch
   or tag specified by the `ref` attribute, since Nix doesn't do a full
@@ -161,6 +161,11 @@ Currently the `type` attribute can be one of the following:
   doesn't allow fetching a `rev` without a known `ref`). The default
   is the commit currently pointed to by `ref`.
 
+  When `git+file` is used without specifying `ref` or `rev`, files are
+  fetched directly from the local `path` as long as they have been added
+  to the Git repository. If there are uncommitted changes, the reference
+  is treated as dirty and a warning is printed.
+
   For example, the following are valid Git flake references:
 
   * `git+https://example.org/my/repo`
@@ -326,9 +331,10 @@ The following attributes are supported in `flake.nix`:
 
 * `nixConfig`: a set of `nix.conf` options to be set when evaluating any
   part of a flake. In the interests of security, only a small set of
-  whitelisted options (currently `bash-prompt`, `bash-prompt-suffix`,
-  and `flake-registry`) are allowed to be set without confirmation so long as
-  `accept-flake-config` is not set in the global configuration.
+  whitelisted options (currently `bash-prompt`, `bash-prompt-prefix`,
+  `bash-prompt-suffix`, and `flake-registry`) are allowed to be set without
+  confirmation so long as `accept-flake-config` is not set in the global
+  configuration.
 
 ## Flake inputs
 
diff --git a/src/nix/fmt.cc b/src/nix/fmt.cc
index e5d44bd38..6f6a4a632 100644
--- a/src/nix/fmt.cc
+++ b/src/nix/fmt.cc
@@ -26,7 +26,8 @@ struct CmdFmt : SourceExprCommand {
 
     Strings getDefaultFlakeAttrPathPrefixes() override { return Strings{}; }
 
-    void run(ref<Store> store) {
+    void run(ref<Store> store) override
+    {
         auto evalState = getEvalState();
         auto evalStore = getEvalStore();
 
diff --git a/src/nix/main.cc b/src/nix/main.cc
index 6d0f6ce6e..dadb54306 100644
--- a/src/nix/main.cc
+++ b/src/nix/main.cc
@@ -261,6 +261,8 @@ void mainWrapped(int argc, char * * argv)
     }
     #endif
 
+    Finally f([] { logger->stop(); });
+
     programPath = argv[0];
     auto programName = std::string(baseNameOf(programPath));
 
@@ -279,8 +281,6 @@ void mainWrapped(int argc, char * * argv)
         verbosity = lvlInfo;
     }
 
-    Finally f([] { logger->stop(); });
-
     NixArgs args;
 
     if (argc == 2 && std::string(argv[1]) == "__dump-args") {
diff --git a/src/nix/nix.md b/src/nix/nix.md
index 0dacadee6..d48682a94 100644
--- a/src/nix/nix.md
+++ b/src/nix/nix.md
@@ -146,6 +146,51 @@ For most commands, if no installable is specified, the default is `.`,
 i.e. Nix will operate on the default flake output attribute of the
 flake in the current directory.
 
+## Derivation output selection
+
+Derivations can have multiple outputs, each corresponding to a
+different store path. For instance, a package can have a `bin` output
+that contains programs, and a `dev` output that provides development
+artifacts like C/C++ header files. The outputs on which `nix` commands
+operate are determined as follows:
+
+* You can explicitly specify the desired outputs using the syntax
+  *installable*`^`*output1*`,`*...*`,`*outputN*. For example, you can
+  obtain the `dev` and `static` outputs of the `glibc` package:
+
+  ```console
+  # nix build 'nixpkgs#glibc^dev,static'
+  # ls ./result-dev/include/ ./result-static/lib/
+  …
+  ```
+
+* You can also specify that *all* outputs should be used using the
+  syntax *installable*`^*`. For example, the following shows the size
+  of all outputs of the `glibc` package in the binary cache:
+
+  ```console
+  # nix path-info -S --eval-store auto --store https://cache.nixos.org 'nixpkgs#glibc^*'
+  /nix/store/g02b1lpbddhymmcjb923kf0l7s9nww58-glibc-2.33-123                 33208200
+  /nix/store/851dp95qqiisjifi639r0zzg5l465ny4-glibc-2.33-123-bin             36142896
+  /nix/store/kdgs3q6r7xdff1p7a9hnjr43xw2404z7-glibc-2.33-123-debug          155787312
+  /nix/store/n4xa8h6pbmqmwnq0mmsz08l38abb06zc-glibc-2.33-123-static          42488328
+  /nix/store/q6580lr01jpcsqs4r5arlh4ki2c1m9rv-glibc-2.33-123-dev             44200560
+  ```
+
+* If you didn't specify the desired outputs, but the derivation has an
+  attribute `meta.outputsToInstall`, Nix will use those outputs. For
+  example, since the package `nixpkgs#libxml2` has this attribute:
+
+  ```console
+  # nix eval 'nixpkgs#libxml2.meta.outputsToInstall'
+  [ "bin" "man" ]
+  ```
+
+  a command like `nix shell nixpkgs#libxml2` will provide only those
+  two outputs by default.
+
+* Otherwise, Nix will use all outputs of the derivation.
+
 # Nix stores
 
 Most `nix` subcommands operate on a *Nix store*.
diff --git a/src/nix/profile-install.md b/src/nix/profile-install.md
index e3009491e..aed414963 100644
--- a/src/nix/profile-install.md
+++ b/src/nix/profile-install.md
@@ -20,6 +20,13 @@ R""(
   # nix profile install nixpkgs/d73407e8e6002646acfdef0e39ace088bacc83da#hello
   ```
 
+* Install a specific output of a package:
+
+  ```console
+  # nix profile install nixpkgs#bash^man
+  ```
+
+
 # Description
 
 This command adds *installables* to a Nix profile.
diff --git a/src/nix/profile.cc b/src/nix/profile.cc
index b151e48d6..1aae347df 100644
--- a/src/nix/profile.cc
+++ b/src/nix/profile.cc
@@ -22,13 +22,13 @@ struct ProfileElementSource
     // FIXME: record original attrpath.
     FlakeRef resolvedRef;
     std::string attrPath;
-    // FIXME: output names
+    OutputsSpec outputs;
 
     bool operator < (const ProfileElementSource & other) const
     {
         return
-            std::pair(originalRef.to_string(), attrPath) <
-            std::pair(other.originalRef.to_string(), other.attrPath);
+            std::tuple(originalRef.to_string(), attrPath, outputs) <
+            std::tuple(other.originalRef.to_string(), other.attrPath, other.outputs);
     }
 };
 
@@ -37,12 +37,12 @@ struct ProfileElement
     StorePathSet storePaths;
     std::optional<ProfileElementSource> source;
     bool active = true;
-    // FIXME: priority
+    int priority = 5;
 
     std::string describe() const
     {
         if (source)
-            return fmt("%s#%s", source->originalRef, source->attrPath);
+            return fmt("%s#%s%s", source->originalRef, source->attrPath, printOutputsSpec(source->outputs));
         StringSet names;
         for (auto & path : storePaths)
             names.insert(DrvName(path.name()).name);
@@ -67,7 +67,6 @@ struct ProfileElement
         ref<Store> store,
         const BuiltPaths & builtPaths)
     {
-        // FIXME: respect meta.outputsToInstall
         storePaths.clear();
         for (auto & buildable : builtPaths) {
             std::visit(overloaded {
@@ -99,7 +98,7 @@ struct ProfileManifest
             auto version = json.value("version", 0);
             std::string sUrl;
             std::string sOriginalUrl;
-            switch(version){
+            switch (version) {
                 case 1:
                     sUrl = "uri";
                     sOriginalUrl = "originalUri";
@@ -117,11 +116,15 @@ struct ProfileManifest
                 for (auto & p : e["storePaths"])
                     element.storePaths.insert(state.store->parseStorePath((std::string) p));
                 element.active = e["active"];
-                if (e.value(sUrl,"") != "") {
-                    element.source = ProfileElementSource{
+                if(e.contains("priority")) {
+                    element.priority = e["priority"];
+                }
+                if (e.value(sUrl, "") != "") {
+                    element.source = ProfileElementSource {
                         parseFlakeRef(e[sOriginalUrl]),
                         parseFlakeRef(e[sUrl]),
-                        e["attrPath"]
+                        e["attrPath"],
+                        e["outputs"].get<OutputsSpec>()
                     };
                 }
                 elements.emplace_back(std::move(element));
@@ -153,10 +156,12 @@ struct ProfileManifest
             nlohmann::json obj;
             obj["storePaths"] = paths;
             obj["active"] = element.active;
+            obj["priority"] = element.priority;
             if (element.source) {
                 obj["originalUrl"] = element.source->originalRef.to_string();
                 obj["url"] = element.source->resolvedRef.to_string();
                 obj["attrPath"] = element.source->attrPath;
+                obj["outputs"] = element.source->outputs;
             }
             array.push_back(obj);
         }
@@ -176,7 +181,7 @@ struct ProfileManifest
         for (auto & element : elements) {
             for (auto & path : element.storePaths) {
                 if (element.active)
-                    pkgs.emplace_back(store->printStorePath(path), true, 5);
+                    pkgs.emplace_back(store->printStorePath(path), true, element.priority);
                 references.insert(path);
             }
         }
@@ -258,6 +263,16 @@ builtPathsPerInstallable(
 
 struct CmdProfileInstall : InstallablesCommand, MixDefaultProfile
 {
+    std::optional<int> priority;
+    CmdProfileInstall() {
+        addFlag({
+            .longName = "priority",
+            .description = "The priority of the package to install.",
+            .labels = {"priority"},
+            .handler = {&priority},
+        });
+    };
+
     std::string description() override
     {
         return "install a package into a profile";
@@ -281,16 +296,27 @@ struct CmdProfileInstall : InstallablesCommand, MixDefaultProfile
         for (auto & installable : installables) {
             ProfileElement element;
 
+
+
             if (auto installable2 = std::dynamic_pointer_cast<InstallableFlake>(installable)) {
                 // FIXME: make build() return this?
                 auto [attrPath, resolvedRef, drv] = installable2->toDerivation();
-                element.source = ProfileElementSource{
+                element.source = ProfileElementSource {
                     installable2->flakeRef,
                     resolvedRef,
                     attrPath,
+                    installable2->outputsSpec
                 };
+
+                if(drv.priority) {
+                    element.priority = *drv.priority;
+                }
             }
 
+            if(priority) { // if --priority was specified we want to override the priority of the installable
+                element.priority = *priority;
+            };
+
             element.updateStorePaths(getEvalStore(), store, builtPaths[installable.get()]);
 
             manifest.elements.push_back(std::move(element));
@@ -444,6 +470,7 @@ struct CmdProfileUpgrade : virtual SourceExprCommand, MixDefaultProfile, MixProf
                     getEvalState(),
                     FlakeRef(element.source->originalRef),
                     "",
+                    element.source->outputs,
                     Strings{element.source->attrPath},
                     Strings{},
                     lockFlags);
@@ -455,10 +482,11 @@ struct CmdProfileUpgrade : virtual SourceExprCommand, MixDefaultProfile, MixProf
                 printInfo("upgrading '%s' from flake '%s' to '%s'",
                     element.source->attrPath, element.source->resolvedRef, resolvedRef);
 
-                element.source = ProfileElementSource{
+                element.source = ProfileElementSource {
                     installable->flakeRef,
                     resolvedRef,
                     attrPath,
+                    installable->outputsSpec
                 };
 
                 installables.push_back(installable);
@@ -514,8 +542,8 @@ struct CmdProfileList : virtual EvalCommand, virtual StoreCommand, MixDefaultPro
         for (size_t i = 0; i < manifest.elements.size(); ++i) {
             auto & element(manifest.elements[i]);
             logger->cout("%d %s %s %s", i,
-                element.source ? element.source->originalRef.to_string() + "#" + element.source->attrPath : "-",
-                element.source ? element.source->resolvedRef.to_string() + "#" + element.source->attrPath : "-",
+                element.source ? element.source->originalRef.to_string() + "#" + element.source->attrPath + printOutputsSpec(element.source->outputs) : "-",
+                element.source ? element.source->resolvedRef.to_string() + "#" + element.source->attrPath + printOutputsSpec(element.source->outputs) : "-",
                 concatStringsSep(" ", store->printStorePathSet(element.storePaths)));
         }
     }
diff --git a/src/nix/repl.cc b/src/nix/repl.cc
index 998ff7328..2967632ed 100644
--- a/src/nix/repl.cc
+++ b/src/nix/repl.cc
@@ -73,7 +73,7 @@ struct NixRepl
     void initEnv();
     void reloadFiles();
     void addAttrsToScope(Value & attrs);
-    void addVarToScope(const SymbolIdx name, Value & v);
+    void addVarToScope(const Symbol name, Value & v);
     Expr * parseString(std::string s);
     void evalString(std::string s, Value & v);
 
@@ -711,7 +711,7 @@ void NixRepl::addAttrsToScope(Value & attrs)
 }
 
 
-void NixRepl::addVarToScope(const SymbolIdx name, Value & v)
+void NixRepl::addVarToScope(const Symbol name, Value & v)
 {
     if (displ >= envSize)
         throw Error("environment full; cannot add more variables");
diff --git a/src/nix/search.cc b/src/nix/search.cc
index 8b1e9ae6c..87dc1c0de 100644
--- a/src/nix/search.cc
+++ b/src/nix/search.cc
@@ -77,13 +77,15 @@ struct CmdSearch : InstallableCommand, MixJSON
 
         visit = [&](eval_cache::AttrCursor & cursor, const std::vector<Symbol> & attrPath, bool initialRecurse)
         {
+            auto attrPathS = state->symbols.resolve(attrPath);
+
             Activity act(*logger, lvlInfo, actUnknown,
-                fmt("evaluating '%s'", concatStringsSep(".", attrPath)));
+                fmt("evaluating '%s'", concatStringsSep(".", attrPathS)));
             try {
                 auto recurse = [&]()
                 {
                     for (const auto & attr : cursor.getAttrs()) {
-                        auto cursor2 = cursor.getAttr(attr);
+                        auto cursor2 = cursor.getAttr(state->symbols[attr]);
                         auto attrPath2(attrPath);
                         attrPath2.push_back(attr);
                         visit(*cursor2, attrPath2, false);
@@ -91,13 +93,13 @@ struct CmdSearch : InstallableCommand, MixJSON
                 };
 
                 if (cursor.isDerivation()) {
-                    DrvName name(cursor.getAttr("name")->getString());
+                    DrvName name(cursor.getAttr(state->sName)->getString());
 
-                    auto aMeta = cursor.maybeGetAttr("meta");
-                    auto aDescription = aMeta ? aMeta->maybeGetAttr("description") : nullptr;
+                    auto aMeta = cursor.maybeGetAttr(state->sMeta);
+                    auto aDescription = aMeta ? aMeta->maybeGetAttr(state->sDescription) : nullptr;
                     auto description = aDescription ? aDescription->getString() : "";
                     std::replace(description.begin(), description.end(), '\n', ' ');
-                    auto attrPath2 = concatStringsSep(".", attrPath);
+                    auto attrPath2 = concatStringsSep(".", attrPathS);
 
                     std::vector<std::smatch> attrPathMatches;
                     std::vector<std::smatch> descriptionMatches;
@@ -146,21 +148,21 @@ struct CmdSearch : InstallableCommand, MixJSON
 
                 else if (
                     attrPath.size() == 0
-                    || (attrPath[0] == "legacyPackages" && attrPath.size() <= 2)
-                    || (attrPath[0] == "packages" && attrPath.size() <= 2))
+                    || (attrPathS[0] == "legacyPackages" && attrPath.size() <= 2)
+                    || (attrPathS[0] == "packages" && attrPath.size() <= 2))
                     recurse();
 
                 else if (initialRecurse)
                     recurse();
 
-                else if (attrPath[0] == "legacyPackages" && attrPath.size() > 2) {
-                    auto attr = cursor.maybeGetAttr("recurseForDerivations");
+                else if (attrPathS[0] == "legacyPackages" && attrPath.size() > 2) {
+                    auto attr = cursor.maybeGetAttr(state->sRecurseForDerivations);
                     if (attr && attr->getBool())
                         recurse();
                 }
 
             } catch (EvalError & e) {
-                if (!(attrPath.size() > 0 && attrPath[0] == "legacyPackages"))
+                if (!(attrPath.size() > 0 && attrPathS[0] == "legacyPackages"))
                     throw;
             }
         };