Tagging release 2.28.0

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2025-11-24 03:09:35 +01:00 · 2025-04-04 17:49:15 +02:00 · 2025-04-04 17:49:15 +02:00 · 852075ec9d
commit 852075ec9d
parent 63d41e72f4 0a66906e55
697 changed files with 4531 additions and 3970 deletions
--- a/src/libexpr/attr-path.cc
+++ b/src/libexpr/attr-path.cc
@ -1,5 +1,5 @@
-#include "attr-path.hh"
-#include "eval-inline.hh"
+#include "nix/expr/attr-path.hh"
+#include "nix/expr/eval-inline.hh"


 namespace nix {
--- a/src/libexpr/attr-set.cc
+++ b/src/libexpr/attr-set.cc
@ -1,5 +1,5 @@
-#include "attr-set.hh"
-#include "eval-inline.hh"
+#include "nix/expr/attr-set.hh"
+#include "nix/expr/eval-inline.hh"

 #include <algorithm>

--- a/src/libexpr/call-flake.nix
+++ b/src/libexpr/call-flake.nix
@ -1,96 +0,0 @@
-# This is a helper to callFlake() to lazily fetch flake inputs.
-
-# The contents of the lock file, in JSON format.
-lockFileStr:
-
-# A mapping of lock file node IDs to { sourceInfo, subdir } attrsets,
-# with sourceInfo.outPath providing an SourceAccessor to a previously
-# fetched tree. This is necessary for possibly unlocked inputs, in
-# particular the root input, but also --override-inputs pointing to
-# unlocked trees.
-overrides:
-
-# This is `prim_fetchFinalTree`.
-fetchTreeFinal:
-
-let
-
-  lockFile = builtins.fromJSON lockFileStr;
-
-  # Resolve a input spec into a node name. An input spec is
-  # either a node name, or a 'follows' path from the root
-  # node.
-  resolveInput =
-    inputSpec: if builtins.isList inputSpec then getInputByPath lockFile.root inputSpec else inputSpec;
-
-  # Follow an input attrpath (e.g. ["dwarffs" "nixpkgs"]) from the
-  # root node, returning the final node.
-  getInputByPath =
-    nodeName: path:
-    if path == [ ] then
-      nodeName
-    else
-      getInputByPath
-        # Since this could be a 'follows' input, call resolveInput.
-        (resolveInput lockFile.nodes.${nodeName}.inputs.${builtins.head path})
-        (builtins.tail path);
-
-  allNodes = builtins.mapAttrs (
-    key: node:
-    let
-
-      parentNode = allNodes.${getInputByPath lockFile.root node.parent};
-
-      sourceInfo =
-        if overrides ? ${key} then
-          overrides.${key}.sourceInfo
-        else if node.locked.type == "path" && builtins.substring 0 1 node.locked.path != "/" then
-          parentNode.sourceInfo
-          // {
-            outPath = parentNode.outPath + ("/" + node.locked.path);
-          }
-        else
-          # FIXME: remove obsolete node.info.
-          # Note: lock file entries are always final.
-          fetchTreeFinal (node.info or { } // removeAttrs node.locked [ "dir" ]);
-
-      subdir = overrides.${key}.dir or node.locked.dir or "";
-
-      outPath = sourceInfo + ((if subdir == "" then "" else "/") + subdir);
-
-      flake = import (outPath + "/flake.nix");
-
-      inputs = builtins.mapAttrs (inputName: inputSpec: allNodes.${resolveInput inputSpec}) (
-        node.inputs or { }
-      );
-
-      outputs = flake.outputs (inputs // { self = result; });
-
-      result =
-        outputs
-        # We add the sourceInfo attribute for its metadata, as they are
-        # relevant metadata for the flake. However, the outPath of the
-        # sourceInfo does not necessarily match the outPath of the flake,
-        # as the flake may be in a subdirectory of a source.
-        # This is shadowed in the next //
-        // sourceInfo
-        // {
-          # This shadows the sourceInfo.outPath
-          inherit outPath;
-
-          inherit inputs;
-          inherit outputs;
-          inherit sourceInfo;
-          _type = "flake";
-        };
-
-    in
-    if node.flake or true then
-      assert builtins.isFunction flake.outputs;
-      result
-    else
-      sourceInfo
-  ) lockFile.nodes;
-
-in
-allNodes.${lockFile.root}
--- a/src/libexpr/eval-cache.cc
+++ b/src/libexpr/eval-cache.cc
@ -1,11 +1,11 @@
-#include "users.hh"
-#include "eval-cache.hh"
-#include "sqlite.hh"
-#include "eval.hh"
-#include "eval-inline.hh"
-#include "store-api.hh"
+#include "nix/util/users.hh"
+#include "nix/expr/eval-cache.hh"
+#include "nix/store/sqlite.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/store/store-api.hh"
 // Need specialization involving `SymbolStr` just in this one module.
-#include "strings-inline.hh"
+#include "nix/util/strings-inline.hh"

 namespace nix::eval_cache {

@ -418,6 +418,14 @@ Value & AttrCursor::getValue()
    return **_value;
 }

+void AttrCursor::fetchCachedValue()
+{
+    if (!cachedValue)
+        cachedValue = root->db->getAttr(getKey());
+    if (cachedValue && std::get_if<failed_t>(&cachedValue->second) && parent)
+        throw CachedEvalError(parent->first, parent->second);
+}
+
 std::vector<Symbol> AttrCursor::getAttrPath() const
 {
    if (parent) {
@ -494,14 +502,13 @@ Suggestions AttrCursor::getSuggestionsForAttr(Symbol name)
 std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(Symbol name)
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();

        if (cachedValue) {
            if (auto attrs = std::get_if<std::vector<Symbol>>(&cachedValue->second)) {
                for (auto & attr : *attrs)
                    if (attr == name)
-                        return std::make_shared<AttrCursor>(root, std::make_pair(shared_from_this(), attr));
+                        return std::make_shared<AttrCursor>(root, std::make_pair(ref(shared_from_this()), attr));
                return nullptr;
            } else if (std::get_if<placeholder_t>(&cachedValue->second)) {
                auto attr = root->db->getAttr({cachedValue->first, name});
@ -512,7 +519,7 @@ std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(Symbol name)
                        throw CachedEvalError(ref(shared_from_this()), name);
                    else
                        return std::make_shared<AttrCursor>(root,
-                            std::make_pair(shared_from_this(), name), nullptr, std::move(attr));
+                            std::make_pair(ref(shared_from_this()), name), nullptr, std::move(attr));
                }
                // Incomplete attrset, so need to fall thru and
                // evaluate to see whether 'name' exists
@ -547,7 +554,7 @@ std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(Symbol name)
    }

    return make_ref<AttrCursor>(
-        root, std::make_pair(shared_from_this(), name), attr->value, std::move(cachedValue2));
+        root, std::make_pair(ref(shared_from_this()), name), attr->value, std::move(cachedValue2));
 }

 std::shared_ptr<AttrCursor> AttrCursor::maybeGetAttr(std::string_view name)
@ -585,8 +592,7 @@ OrSuggestions<ref<AttrCursor>> AttrCursor::findAlongAttrPath(const std::vector<S
 std::string AttrCursor::getString()
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();
        if (cachedValue && !std::get_if<placeholder_t>(&cachedValue->second)) {
            if (auto s = std::get_if<string_t>(&cachedValue->second)) {
                debug("using cached string attribute '%s'", getAttrPathStr());
@ -607,8 +613,7 @@ std::string AttrCursor::getString()
 string_t AttrCursor::getStringWithContext()
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();
        if (cachedValue && !std::get_if<placeholder_t>(&cachedValue->second)) {
            if (auto s = std::get_if<string_t>(&cachedValue->second)) {
                bool valid = true;
@ -654,8 +659,7 @@ string_t AttrCursor::getStringWithContext()
 bool AttrCursor::getBool()
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();
        if (cachedValue && !std::get_if<placeholder_t>(&cachedValue->second)) {
            if (auto b = std::get_if<bool>(&cachedValue->second)) {
                debug("using cached Boolean attribute '%s'", getAttrPathStr());
@ -676,8 +680,7 @@ bool AttrCursor::getBool()
 NixInt AttrCursor::getInt()
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();
        if (cachedValue && !std::get_if<placeholder_t>(&cachedValue->second)) {
            if (auto i = std::get_if<int_t>(&cachedValue->second)) {
                debug("using cached integer attribute '%s'", getAttrPathStr());
@ -698,8 +701,7 @@ NixInt AttrCursor::getInt()
 std::vector<std::string> AttrCursor::getListOfStrings()
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();
        if (cachedValue && !std::get_if<placeholder_t>(&cachedValue->second)) {
            if (auto l = std::get_if<std::vector<std::string>>(&cachedValue->second)) {
                debug("using cached list of strings attribute '%s'", getAttrPathStr());
@ -731,8 +733,7 @@ std::vector<std::string> AttrCursor::getListOfStrings()
 std::vector<Symbol> AttrCursor::getAttrs()
 {
    if (root->db) {
-        if (!cachedValue)
-            cachedValue = root->db->getAttr(getKey());
+        fetchCachedValue();
        if (cachedValue && !std::get_if<placeholder_t>(&cachedValue->second)) {
            if (auto attrs = std::get_if<std::vector<Symbol>>(&cachedValue->second)) {
                debug("using cached attrset attribute '%s'", getAttrPathStr());
--- a/src/libexpr/eval-error.cc
+++ b/src/libexpr/eval-error.cc
@ -1,6 +1,6 @@
-#include "eval-error.hh"
-#include "eval.hh"
-#include "value.hh"
+#include "nix/expr/eval-error.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/value.hh"

 namespace nix {

--- a/src/libexpr/eval-gc.cc
+++ b/src/libexpr/eval-gc.cc
@ -1,11 +1,13 @@
-#include "error.hh"
-#include "environment-variables.hh"
-#include "eval-settings.hh"
-#include "config-global.hh"
-#include "serialise.hh"
-#include "eval-gc.hh"
+#include "nix/util/error.hh"
+#include "nix/util/environment-variables.hh"
+#include "nix/expr/eval-settings.hh"
+#include "nix/util/config-global.hh"
+#include "nix/util/serialise.hh"
+#include "nix/expr/eval-gc.hh"

-#if HAVE_BOEHMGC
+#include "expr-config-private.hh"
+
+#if NIX_USE_BOEHMGC

 #  include <pthread.h>
 #  if __FreeBSD__
@ -24,7 +26,7 @@

 namespace nix {

-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
 /* Called when the Boehm GC runs out of memory. */
 static void * oomHandler(size_t requested)
 {
@ -94,7 +96,7 @@ void initGC()
    if (gcInitialised)
        return;

-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    initGCReal();

    gcCyclesAfterInit = GC_get_gc_no();
--- a/src/libexpr/eval-settings.cc
+++ b/src/libexpr/eval-settings.cc
@ -1,8 +1,8 @@
-#include "users.hh"
-#include "globals.hh"
-#include "profiles.hh"
-#include "eval.hh"
-#include "eval-settings.hh"
+#include "nix/util/users.hh"
+#include "nix/store/globals.hh"
+#include "nix/store/profiles.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/eval-settings.hh"

 namespace nix {

@ -103,4 +103,4 @@ Path getNixDefExpr()
        : getHome() + "/.nix-defexpr";
 }

-}
+} // namespace nix
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@ -1,25 +1,26 @@
-#include "eval.hh"
-#include "eval-settings.hh"
-#include "primops.hh"
-#include "print-options.hh"
-#include "exit.hh"
-#include "types.hh"
-#include "util.hh"
-#include "store-api.hh"
-#include "derivations.hh"
-#include "downstream-placeholder.hh"
-#include "eval-inline.hh"
-#include "filetransfer.hh"
-#include "function-trace.hh"
-#include "profiles.hh"
-#include "print.hh"
-#include "filtering-source-accessor.hh"
-#include "memory-source-accessor.hh"
-#include "mounted-source-accessor.hh"
-#include "gc-small-vector.hh"
-#include "url.hh"
-#include "fetch-to-store.hh"
-#include "tarball.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/eval-settings.hh"
+#include "nix/expr/primops.hh"
+#include "nix/expr/print-options.hh"
+#include "nix/util/exit.hh"
+#include "nix/util/types.hh"
+#include "nix/util/util.hh"
+#include "nix/store/store-api.hh"
+#include "nix/store/derivations.hh"
+#include "nix/store/downstream-placeholder.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/store/filetransfer.hh"
+#include "nix/expr/function-trace.hh"
+#include "nix/store/profiles.hh"
+#include "nix/expr/print.hh"
+#include "nix/fetchers/filtering-source-accessor.hh"
+#include "nix/util/memory-source-accessor.hh"
+#include "nix/util/mounted-source-accessor.hh"
+#include "nix/expr/gc-small-vector.hh"
+#include "nix/util/url.hh"
+#include "nix/fetchers/fetch-to-store.hh"
+#include "nix/fetchers/tarball.hh"
+
 #include "parser-tab.hh"

 #include <algorithm>
@ -39,7 +40,7 @@
 #  include <sys/resource.h>
 #endif

-#include "strings-inline.hh"
+#include "nix/util/strings-inline.hh"

 using json = nlohmann::json;

@ -290,17 +291,13 @@ EvalState::EvalState(
        CanonPath("derivation-internal.nix"),
        #include "primops/derivation.nix.gen.hh"
    )}
-    , callFlakeInternal{internalFS->addFile(
-        CanonPath("call-flake.nix"),
-        #include "call-flake.nix.gen.hh"
-    )}
    , store(store)
    , buildStore(buildStore ? buildStore : store)
    , debugRepl(nullptr)
    , debugStop(false)
    , trylevel(0)
    , regexCache(makeRegexCache())
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    , valueAllocCache(std::allocate_shared<void *>(traceable_allocator<void *>(), nullptr))
    , env1AllocCache(std::allocate_shared<void *>(traceable_allocator<void *>(), nullptr))
    , baseEnvP(std::allocate_shared<Env *>(traceable_allocator<Env *>(), &allocEnv(BASE_ENV_SIZE)))
@ -355,7 +352,7 @@ EvalState::EvalState(
        #include "fetchurl.nix.gen.hh"
    );

-    createBaseEnv();
+    createBaseEnv(settings);
 }


@ -2251,18 +2248,18 @@ std::string_view EvalState::forceString(Value & v, const PosIdx pos, std::string
 }


-void copyContext(const Value & v, NixStringContext & context)
+void copyContext(const Value & v, NixStringContext & context, const ExperimentalFeatureSettings & xpSettings)
 {
    if (v.payload.string.context)
        for (const char * * p = v.payload.string.context; *p; ++p)
-            context.insert(NixStringContextElem::parse(*p));
+            context.insert(NixStringContextElem::parse(*p, xpSettings));
 }


-std::string_view EvalState::forceString(Value & v, NixStringContext & context, const PosIdx pos, std::string_view errorCtx)
+std::string_view EvalState::forceString(Value & v, NixStringContext & context, const PosIdx pos, std::string_view errorCtx, const ExperimentalFeatureSettings & xpSettings)
 {
    auto s = forceString(v, pos, errorCtx);
-    copyContext(v, context);
+    copyContext(v, context, xpSettings);
    return s;
 }

@ -2468,10 +2465,10 @@ StorePath EvalState::coerceToStorePath(const PosIdx pos, Value & v, NixStringCon
 }


-std::pair<SingleDerivedPath, std::string_view> EvalState::coerceToSingleDerivedPathUnchecked(const PosIdx pos, Value & v, std::string_view errorCtx)
+std::pair<SingleDerivedPath, std::string_view> EvalState::coerceToSingleDerivedPathUnchecked(const PosIdx pos, Value & v, std::string_view errorCtx, const ExperimentalFeatureSettings & xpSettings)
 {
    NixStringContext context;
-    auto s = forceString(v, context, pos, errorCtx);
+    auto s = forceString(v, context, pos, errorCtx, xpSettings);
    auto csize = context.size();
    if (csize != 1)
        error<EvalError>(
@ -2817,7 +2814,7 @@ bool EvalState::eqValues(Value & v1, Value & v2, const PosIdx pos, std::string_v
 }

 bool EvalState::fullGC() {
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    GC_gcollect();
    // Check that it ran. We might replace this with a version that uses more
    // of the boehm API to get this reliably, at a maintenance cost.
@ -2836,7 +2833,7 @@ void EvalState::maybePrintStats()

    if (showStats) {
        // Make the final heap size more deterministic.
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
        if (!fullGC()) {
            warn("failed to perform a full GC before reporting stats");
        }
@ -2858,7 +2855,7 @@ void EvalState::printStatistics()
    uint64_t bValues = nrValues * sizeof(Value);
    uint64_t bAttrsets = nrAttrsets * sizeof(Bindings) + nrAttrsInAttrsets * sizeof(Attr);

-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    GC_word heapSize, totalBytes;
    GC_get_heap_usage_safe(&heapSize, 0, 0, 0, &totalBytes);
    double gcFullOnlyTime = ({
@ -2880,7 +2877,7 @@ void EvalState::printStatistics()
 #ifndef _WIN32 // TODO implement
        {"cpu", cpuTime},
 #endif
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
        {GC_is_incremental_mode() ? "gcNonIncremental" : "gc", gcFullOnlyTime},
 #ifndef _WIN32 // TODO implement
        {GC_is_incremental_mode() ? "gcNonIncrementalFraction" : "gcFraction", gcFullOnlyTime / cpuTime},
@ -2924,7 +2921,7 @@ void EvalState::printStatistics()
    topObj["nrLookups"] = nrLookups;
    topObj["nrPrimOpCalls"] = nrPrimOpCalls;
    topObj["nrFunctionCalls"] = nrFunctionCalls;
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    topObj["gc"] = {
        {"heapSize", heapSize},
        {"totalBytes", totalBytes},
--- a/src/libexpr/function-trace.cc
+++ b/src/libexpr/function-trace.cc
@ -1,5 +1,5 @@
-#include "function-trace.hh"
-#include "logging.hh"
+#include "nix/expr/function-trace.hh"
+#include "nix/util/logging.hh"

 namespace nix {

--- a/src/libexpr/get-drvs.cc
+++ b/src/libexpr/get-drvs.cc
@ -1,8 +1,8 @@
-#include "get-drvs.hh"
-#include "eval-inline.hh"
-#include "derivations.hh"
-#include "store-api.hh"
-#include "path-with-outputs.hh"
+#include "nix/expr/get-drvs.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/store/derivations.hh"
+#include "nix/store/store-api.hh"
+#include "nix/store/path-with-outputs.hh"

 #include <cstring>
 #include <regex>
--- a/src/libexpr/include/nix/expr/attr-path.hh
+++ b/src/libexpr/include/nix/expr/attr-path.hh
@ -1,7 +1,7 @@
 #pragma once
 ///@file

-#include "eval.hh"
+#include "nix/expr/eval.hh"

 #include <string>
 #include <map>
--- a/src/libexpr/include/nix/expr/attr-set.hh
+++ b/src/libexpr/include/nix/expr/attr-set.hh
@ -1,8 +1,8 @@
 #pragma once
 ///@file

-#include "nixexpr.hh"
-#include "symbol-table.hh"
+#include "nix/expr/nixexpr.hh"
+#include "nix/expr/symbol-table.hh"

 #include <algorithm>

--- a/src/libexpr/include/nix/expr/eval-cache.hh
+++ b/src/libexpr/include/nix/expr/eval-cache.hh
@ -1,9 +1,9 @@
 #pragma once
 ///@file

-#include "sync.hh"
-#include "hash.hh"
-#include "eval.hh"
+#include "nix/util/sync.hh"
+#include "nix/util/hash.hh"
+#include "nix/expr/eval.hh"

 #include <functional>
 #include <variant>
@ -90,7 +90,7 @@ class AttrCursor : public std::enable_shared_from_this<AttrCursor>
    friend struct CachedEvalError;

    ref<EvalCache> root;
-    typedef std::optional<std::pair<std::shared_ptr<AttrCursor>, Symbol>> Parent;
+    using Parent = std::optional<std::pair<ref<AttrCursor>, Symbol>>;
    Parent parent;
    RootValue _value;
    std::optional<std::pair<AttrId, AttrValue>> cachedValue;
@ -99,6 +99,14 @@ class AttrCursor : public std::enable_shared_from_this<AttrCursor>

    Value & getValue();

+    /**
+     * If `cachedValue` is unset, try to initialize it from the
+     * database. It is not an error if it does not exist. Throw a
+     * `CachedEvalError` exception if it does exist but has type
+     * `AttrType::Failed`.
+     */
+    void fetchCachedValue();
+
 public:

    AttrCursor(
--- a/src/libexpr/include/nix/expr/eval-error.hh
+++ b/src/libexpr/include/nix/expr/eval-error.hh
@ -1,7 +1,7 @@
 #pragma once

-#include "error.hh"
-#include "pos-idx.hh"
+#include "nix/util/error.hh"
+#include "nix/util/pos-idx.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/eval-gc.hh
+++ b/src/libexpr/include/nix/expr/eval-gc.hh
@ -3,7 +3,10 @@

 #include <cstddef>

-#if HAVE_BOEHMGC
+// For `NIX_USE_BOEHMGC`, and if that's set, `GC_THREADS`
+#include "nix/expr/config.hh"
+
+#if NIX_USE_BOEHMGC

 #  define GC_INCLUDE_NEW

@ -43,7 +46,7 @@ void initGC();
 */
 void assertGCInitialized();

-#ifdef HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
 /**
 * The number of GC cycles since initGC().
 */
--- a/src/libexpr/include/nix/expr/eval-inline.hh
+++ b/src/libexpr/include/nix/expr/eval-inline.hh
@ -1,10 +1,13 @@
 #pragma once
 ///@file

-#include "print.hh"
-#include "eval.hh"
-#include "eval-error.hh"
-#include "eval-settings.hh"
+#include "nix/expr/print.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/eval-error.hh"
+#include "nix/expr/eval-settings.hh"
+
+// For `NIX_USE_BOEHMGC`, and if that's set, `GC_THREADS`
+#include "nix/expr/config.hh"

 namespace nix {

@ -15,7 +18,7 @@ namespace nix {
 inline void * allocBytes(size_t n)
 {
    void * p;
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    p = GC_MALLOC(n);
 #else
    p = calloc(n, 1);
@ -28,7 +31,7 @@ inline void * allocBytes(size_t n)
 [[gnu::always_inline]]
 Value * EvalState::allocValue()
 {
-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    /* We use the boehm batch allocator to speed up allocations of Values (of which there are many).
       GC_malloc_many returns a linked list of objects of the given size, where the first word
       of each object is also the pointer to the next object in the list. This also means that we
@ -60,7 +63,7 @@ Env & EvalState::allocEnv(size_t size)

    Env * env;

-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    if (size == 1) {
        /* see allocValue for explanations. */
        if (!*env1AllocCache) {
--- a/src/libexpr/include/nix/expr/eval-settings.hh
+++ b/src/libexpr/include/nix/expr/eval-settings.hh
@ -1,12 +1,13 @@
 #pragma once
 ///@file

-#include "config.hh"
-#include "source-path.hh"
+#include "nix/util/configuration.hh"
+#include "nix/util/source-path.hh"

 namespace nix {

 class EvalState;
+struct PrimOp;

 struct EvalSettings : Config
 {
@ -50,6 +51,8 @@ struct EvalSettings : Config

    LookupPathHooks lookupPathHooks;

+    std::vector<PrimOp> extraPrimOps;
+
    Setting<bool> enableNativeCode{this, false, "allow-unsafe-native-code-during-evaluation", R"(
        Enable built-in functions that allow executing native code.

--- a/src/libexpr/include/nix/expr/eval.hh
+++ b/src/libexpr/include/nix/expr/eval.hh
@ -1,20 +1,23 @@
 #pragma once
 ///@file

-#include "attr-set.hh"
-#include "eval-error.hh"
-#include "types.hh"
-#include "value.hh"
-#include "nixexpr.hh"
-#include "symbol-table.hh"
-#include "config.hh"
-#include "experimental-features.hh"
-#include "position.hh"
-#include "pos-table.hh"
-#include "source-accessor.hh"
-#include "search-path.hh"
-#include "repl-exit-status.hh"
-#include "ref.hh"
+#include "nix/expr/attr-set.hh"
+#include "nix/expr/eval-error.hh"
+#include "nix/util/types.hh"
+#include "nix/expr/value.hh"
+#include "nix/expr/nixexpr.hh"
+#include "nix/expr/symbol-table.hh"
+#include "nix/util/configuration.hh"
+#include "nix/util/experimental-features.hh"
+#include "nix/util/position.hh"
+#include "nix/util/pos-table.hh"
+#include "nix/util/source-accessor.hh"
+#include "nix/expr/search-path.hh"
+#include "nix/expr/repl-exit-status.hh"
+#include "nix/util/ref.hh"
+
+// For `NIX_USE_BOEHMGC`, and if that's set, `GC_THREADS`
+#include "nix/expr/config.hh"

 #include <map>
 #include <optional>
@ -160,7 +163,7 @@ void printEnvBindings(const SymbolTable & st, const StaticEnv & se, const Env &

 std::unique_ptr<ValMap> mapStaticEnvBindings(const SymbolTable & st, const StaticEnv & se, const Env & env);

-void copyContext(const Value & v, NixStringContext & context);
+void copyContext(const Value & v, NixStringContext & context, const ExperimentalFeatureSettings & xpSettings = experimentalFeatureSettings);


 std::string printValue(EvalState & state, Value & v);
@ -280,14 +283,12 @@ public:

    /**
     * In-memory filesystem for internal, non-user-callable Nix
-     * expressions like call-flake.nix.
+     * expressions like `derivation.nix`.
     */
    const ref<MemorySourceAccessor> internalFS;

    const SourcePath derivationInternal;

-    const SourcePath callFlakeInternal;
-
    /**
     * Store used to materialise .drv files.
     */
@ -377,7 +378,7 @@ private:
     */
    std::shared_ptr<RegexCache> regexCache;

-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    /**
     * Allocation cache for GC'd Value objects.
     */
@ -533,7 +534,7 @@ public:
     */
    void forceFunction(Value & v, const PosIdx pos, std::string_view errorCtx);
    std::string_view forceString(Value & v, const PosIdx pos, std::string_view errorCtx);
-    std::string_view forceString(Value & v, NixStringContext & context, const PosIdx pos, std::string_view errorCtx);
+    std::string_view forceString(Value & v, NixStringContext & context, const PosIdx pos, std::string_view errorCtx, const ExperimentalFeatureSettings & xpSettings = experimentalFeatureSettings);
    std::string_view forceStringNoCtx(Value & v, const PosIdx pos, std::string_view errorCtx);

    template<typename... Args>
@ -585,7 +586,7 @@ public:
    /**
     * Part of `coerceToSingleDerivedPath()` without any store IO which is exposed for unit testing only.
     */
-    std::pair<SingleDerivedPath, std::string_view> coerceToSingleDerivedPathUnchecked(const PosIdx pos, Value & v, std::string_view errorCtx);
+    std::pair<SingleDerivedPath, std::string_view> coerceToSingleDerivedPathUnchecked(const PosIdx pos, Value & v, std::string_view errorCtx, const ExperimentalFeatureSettings & xpSettings = experimentalFeatureSettings);

    /**
     * Coerce to `SingleDerivedPath`.
@ -604,7 +605,7 @@ public:
     */
    SingleDerivedPath coerceToSingleDerivedPath(const PosIdx pos, Value & v, std::string_view errorCtx);

-#if HAVE_BOEHMGC
+#if NIX_USE_BOEHMGC
    /** A GC root for the baseEnv reference. */
    std::shared_ptr<Env *> baseEnvP;
 #endif
@ -639,7 +640,7 @@ private:

    unsigned int baseEnvDispl = 0;

-    void createBaseEnv();
+    void createBaseEnv(const EvalSettings & settings);

    Value * addConstant(const std::string & name, Value & v, Constant info);

@ -952,4 +953,4 @@ bool isAllowedURI(std::string_view uri, const Strings & allowedPaths);

 }

-#include "eval-inline.hh"
+#include "nix/expr/eval-inline.hh"
--- a/src/libexpr/include/nix/expr/function-trace.hh
+++ b/src/libexpr/include/nix/expr/function-trace.hh
@ -1,7 +1,7 @@
 #pragma once
 ///@file

-#include "eval.hh"
+#include "nix/expr/eval.hh"

 #include <chrono>

--- a/src/libexpr/include/nix/expr/gc-small-vector.hh
+++ b/src/libexpr/include/nix/expr/gc-small-vector.hh
@ -2,7 +2,7 @@

 #include <boost/container/small_vector.hpp>

-#include "value.hh"
+#include "nix/expr/value.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/get-drvs.hh
+++ b/src/libexpr/include/nix/expr/get-drvs.hh
@ -1,8 +1,8 @@
 #pragma once
 ///@file

-#include "eval.hh"
-#include "path.hh"
+#include "nix/expr/eval.hh"
+#include "nix/store/path.hh"

 #include <string>
 #include <map>
--- a/src/libexpr/include/nix/expr/json-to-value.hh
+++ b/src/libexpr/include/nix/expr/json-to-value.hh
@ -1,7 +1,7 @@
 #pragma once
 ///@file

-#include "error.hh"
+#include "nix/util/error.hh"

 #include <string>

--- a/src/libexpr/include/nix/expr/lexer-helpers.hh
+++ b/src/libexpr/include/nix/expr/lexer-helpers.hh
--- a/src/libexpr/include/nix/expr/meson.build
+++ b/src/libexpr/include/nix/expr/meson.build
@ -0,0 +1,37 @@
+# Public headers directory
+
+include_dirs = [include_directories('../..')]
+
+config_pub_h = configure_file(
+  configuration : configdata_pub,
+  output : 'config.hh',
+)
+
+headers = [config_pub_h] + files(
+  'attr-path.hh',
+  'attr-set.hh',
+  'eval-cache.hh',
+  'eval-error.hh',
+  'eval-gc.hh',
+  'eval-inline.hh',
+  'eval-settings.hh',
+  'eval.hh',
+  'function-trace.hh',
+  'gc-small-vector.hh',
+  'get-drvs.hh',
+  'json-to-value.hh',
+  # internal: 'lexer-helpers.hh',
+  'nixexpr.hh',
+  'parser-state.hh',
+  'primops.hh',
+  'print-ambiguous.hh',
+  'print-options.hh',
+  'print.hh',
+  'repl-exit-status.hh',
+  'search-path.hh',
+  'symbol-table.hh',
+  'value-to-json.hh',
+  'value-to-xml.hh',
+  'value.hh',
+  'value/context.hh',
+)
--- a/src/libexpr/include/nix/expr/nixexpr.hh
+++ b/src/libexpr/include/nix/expr/nixexpr.hh
@ -4,10 +4,10 @@
 #include <map>
 #include <vector>

-#include "value.hh"
-#include "symbol-table.hh"
-#include "eval-error.hh"
-#include "pos-idx.hh"
+#include "nix/expr/value.hh"
+#include "nix/expr/symbol-table.hh"
+#include "nix/expr/eval-error.hh"
+#include "nix/util/pos-idx.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/parser-state.hh
+++ b/src/libexpr/include/nix/expr/parser-state.hh
@ -3,7 +3,7 @@

 #include <limits>

-#include "eval.hh"
+#include "nix/expr/eval.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/primops.hh
+++ b/src/libexpr/include/nix/expr/primops.hh
@ -1,7 +1,7 @@
 #pragma once
 ///@file

-#include "eval.hh"
+#include "nix/expr/eval.hh"

 #include <tuple>
 #include <vector>
--- a/src/libexpr/include/nix/expr/print-ambiguous.hh
+++ b/src/libexpr/include/nix/expr/print-ambiguous.hh
@ -1,6 +1,6 @@
 #pragma once

-#include "value.hh"
+#include "nix/expr/value.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/print-options.hh
+++ b/src/libexpr/include/nix/expr/print-options.hh
--- a/src/libexpr/include/nix/expr/print.hh
+++ b/src/libexpr/include/nix/expr/print.hh
@ -9,8 +9,8 @@

 #include <iostream>

-#include "fmt.hh"
-#include "print-options.hh"
+#include "nix/util/fmt.hh"
+#include "nix/expr/print-options.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/repl-exit-status.hh
+++ b/src/libexpr/include/nix/expr/repl-exit-status.hh
--- a/src/libexpr/include/nix/expr/search-path.hh
+++ b/src/libexpr/include/nix/expr/search-path.hh
@ -3,8 +3,8 @@

 #include <optional>

-#include "types.hh"
-#include "comparator.hh"
+#include "nix/util/types.hh"
+#include "nix/util/comparator.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/symbol-table.hh
+++ b/src/libexpr/include/nix/expr/symbol-table.hh
@ -5,9 +5,9 @@
 #include <map>
 #include <unordered_map>

-#include "types.hh"
-#include "chunked-vector.hh"
-#include "error.hh"
+#include "nix/util/types.hh"
+#include "nix/util/chunked-vector.hh"
+#include "nix/util/error.hh"

 namespace nix {

--- a/src/libexpr/include/nix/expr/value-to-json.hh
+++ b/src/libexpr/include/nix/expr/value-to-json.hh
@ -1,8 +1,8 @@
 #pragma once
 ///@file

-#include "nixexpr.hh"
-#include "eval.hh"
+#include "nix/expr/nixexpr.hh"
+#include "nix/expr/eval.hh"

 #include <string>
 #include <map>
--- a/src/libexpr/include/nix/expr/value-to-xml.hh
+++ b/src/libexpr/include/nix/expr/value-to-xml.hh
@ -1,8 +1,8 @@
 #pragma once
 ///@file

-#include "nixexpr.hh"
-#include "eval.hh"
+#include "nix/expr/nixexpr.hh"
+#include "nix/expr/eval.hh"

 #include <string>
 #include <map>
--- a/src/libexpr/include/nix/expr/value.hh
+++ b/src/libexpr/include/nix/expr/value.hh
@ -4,12 +4,12 @@
 #include <cassert>
 #include <span>

-#include "eval-gc.hh"
-#include "symbol-table.hh"
-#include "value/context.hh"
-#include "source-path.hh"
-#include "print-options.hh"
-#include "checked-arithmetic.hh"
+#include "nix/expr/eval-gc.hh"
+#include "nix/expr/symbol-table.hh"
+#include "nix/expr/value/context.hh"
+#include "nix/util/source-path.hh"
+#include "nix/expr/print-options.hh"
+#include "nix/util/checked-arithmetic.hh"

 #include <nlohmann/json_fwd.hpp>

--- a/src/libexpr/include/nix/expr/value/context.hh
+++ b/src/libexpr/include/nix/expr/value/context.hh
@ -1,9 +1,9 @@
 #pragma once
 ///@file

-#include "comparator.hh"
-#include "derived-path.hh"
-#include "variant-wrapper.hh"
+#include "nix/util/comparator.hh"
+#include "nix/store/derived-path.hh"
+#include "nix/util/variant-wrapper.hh"

 #include <nlohmann/json_fwd.hpp>

--- a/src/libexpr/json-to-value.cc
+++ b/src/libexpr/json-to-value.cc
@ -1,6 +1,6 @@
-#include "json-to-value.hh"
-#include "value.hh"
-#include "eval.hh"
+#include "nix/expr/json-to-value.hh"
+#include "nix/expr/value.hh"
+#include "nix/expr/eval.hh"

 #include <limits>
 #include <variant>
--- a/src/libexpr/lexer-helpers.cc
+++ b/src/libexpr/lexer-helpers.cc
@ -1,7 +1,8 @@
 #include "lexer-tab.hh"
-#include "lexer-helpers.hh"
 #include "parser-tab.hh"

+#include "nix/expr/lexer-helpers.hh"
+
 void nix::lexer::internal::initLoc(YYLTYPE * loc)
 {
    loc->beginOffset = loc->endOffset = 0;
--- a/src/libexpr/lexer.l
+++ b/src/libexpr/lexer.l
@ -16,7 +16,7 @@

 %top {
 #include "parser-tab.hh" // YYSTYPE
-#include "parser-state.hh"
+#include "nix/expr/parser-state.hh"
 }

 %{
@ -24,9 +24,9 @@
 #pragma clang diagnostic ignored "-Wunneeded-internal-declaration"
 #endif

-#include "nixexpr.hh"
+#include "nix/expr/nixexpr.hh"
 #include "parser-tab.hh"
-#include "lexer-helpers.hh"
+#include "nix/expr/lexer-helpers.hh"

 namespace nix {
  struct LexerState;
--- a/src/libexpr/meson.build
+++ b/src/libexpr/meson.build
@ -14,7 +14,8 @@ cxx = meson.get_compiler('cpp')

 subdir('nix-meson-build-support/deps-lists')

-configdata = configuration_data()
+configdata_pub = configuration_data()
+configdata_priv = configuration_data()

 deps_private_maybe_subproject = [
 ]
@ -26,6 +27,16 @@ deps_public_maybe_subproject = [
 subdir('nix-meson-build-support/subprojects')
 subdir('nix-meson-build-support/big-objs')

+# Check for each of these functions, and create a define like `#define HAVE_LCHOWN 1`.
+check_funcs = [
+  'sysconf',
+]
+foreach funcspec : check_funcs
+  define_name = 'HAVE_' + funcspec.underscorify().to_upper()
+  define_value = cxx.has_function(funcspec).to_int()
+  configdata_priv.set(define_name, define_value)
+endforeach
+
 boost = dependency(
  'boost',
  modules : ['container', 'context'],
@ -47,11 +58,13 @@ if bdw_gc.found()
  ]
    define_name = 'HAVE_' + funcspec.underscorify().to_upper()
    define_value = cxx.has_function(funcspec).to_int()
-    configdata.set(define_name, define_value)
+    configdata_priv.set(define_name, define_value)
  endforeach
-  configdata.set('GC_THREADS', 1)
+  # Affects ABI, because it changes what bdw_gc itself does!
+  configdata_pub.set('GC_THREADS', 1)
 endif
-configdata.set('HAVE_BOEHMGC', bdw_gc.found().to_int())
+# Used in public header. Affects ABI!
+configdata_pub.set('NIX_USE_BOEHMGC', bdw_gc.found().to_int())

 toml11 = dependency(
  'toml11',
@ -61,19 +74,9 @@ toml11 = dependency(
 )
 deps_other += toml11

-config_h = configure_file(
-  configuration : configdata,
-  output : 'config-expr.hh',
-)
-
-add_project_arguments(
-  # TODO(Qyriad): Yes this is how the autoconf+Make system did it.
-  # It would be nice for our headers to be idempotent instead.
-  '-include', 'config-util.hh',
-  '-include', 'config-store.hh',
-  # '-include', 'config-fetchers.h',
-  '-include', 'config-expr.hh',
-  language : 'cpp',
+config_priv_h = configure_file(
+  configuration : configdata_priv,
+  output : 'expr-config-private.hh',
 )

 subdir('nix-meson-build-support/common')
@ -126,7 +129,6 @@ generated_headers = []
 foreach header : [
  'imported-drv-to-derivation.nix',
  'fetchurl.nix',
-  'call-flake.nix',
 ]
  generated_headers += gen_header.process(header)
 endforeach
@ -154,51 +156,28 @@ sources = files(
  'value/context.cc',
 )

-include_dirs = [include_directories('.')]
-
-headers = [config_h] + files(
-  'attr-path.hh',
-  'attr-set.hh',
-  'eval-cache.hh',
-  'eval-error.hh',
-  'eval-gc.hh',
-  'eval-inline.hh',
-  'eval-settings.hh',
-  'eval.hh',
-  'function-trace.hh',
-  'gc-small-vector.hh',
-  'get-drvs.hh',
-  'json-to-value.hh',
-  # internal: 'lexer-helpers.hh',
-  'nixexpr.hh',
-  'parser-state.hh',
-  'primops.hh',
-  'print-ambiguous.hh',
-  'print-options.hh',
-  'print.hh',
-  'repl-exit-status.hh',
-  'search-path.hh',
-  'symbol-table.hh',
-  'value-to-json.hh',
-  'value-to-xml.hh',
-  'value.hh',
-  'value/context.hh',
-)
+subdir('include/nix/expr')

 subdir('primops')

+subdir('nix-meson-build-support/export-all-symbols')
+subdir('nix-meson-build-support/windows-version')
+
 this_library = library(
  'nixexpr',
  sources,
+  config_priv_h,
  parser_tab,
  lexer_tab,
  generated_headers,
  dependencies : deps_public + deps_private + deps_other,
+  include_directories : include_dirs,
+  link_args: linker_export_flags,
  prelink : true, # For C++ static initializers
  install : true,
 )

-install_headers(headers, subdir : 'nix', preserve_path : true)
+install_headers(headers, subdir : 'nix/expr', preserve_path : true)

 libraries_private = []

--- a/src/libexpr/nixexpr.cc
+++ b/src/libexpr/nixexpr.cc
@ -1,13 +1,13 @@
-#include "nixexpr.hh"
-#include "eval.hh"
-#include "symbol-table.hh"
-#include "util.hh"
-#include "print.hh"
+#include "nix/expr/nixexpr.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/symbol-table.hh"
+#include "nix/util/util.hh"
+#include "nix/expr/print.hh"

 #include <cstdlib>
 #include <sstream>

-#include "strings-inline.hh"
+#include "nix/util/strings-inline.hh"

 namespace nix {

--- a/src/libexpr/package.nix
+++ b/src/libexpr/package.nix
@ -48,6 +48,7 @@ mkMesonLibrary (finalAttrs: {
    ./meson.build
    ./meson.options
    ./primops/meson.build
+    ./include/nix/expr/meson.build
    (fileset.fileFilter (file: file.hasExt "cc") ./.)
    (fileset.fileFilter (file: file.hasExt "hh") ./.)
    ./lexer.l
@ -81,13 +82,6 @@ mkMesonLibrary (finalAttrs: {
    (lib.mesonEnable "gc" enableGC)
  ];

-  env = {
-    # Needed for Meson to find Boost.
-    # https://github.com/NixOS/nixpkgs/issues/86131.
-    BOOST_INCLUDEDIR = "${lib.getDev boost}/include";
-    BOOST_LIBRARYDIR = "${lib.getLib boost}/lib";
-  };
-
  meta = {
    platforms = lib.platforms.unix ++ lib.platforms.windows;
  };
--- a/src/libexpr/parser.y
+++ b/src/libexpr/parser.y
@ -17,14 +17,14 @@

 #include <variant>

-#include "finally.hh"
-#include "util.hh"
-#include "users.hh"
+#include "nix/util/finally.hh"
+#include "nix/util/util.hh"
+#include "nix/util/users.hh"

-#include "nixexpr.hh"
-#include "eval.hh"
-#include "eval-settings.hh"
-#include "parser-state.hh"
+#include "nix/expr/nixexpr.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/eval-settings.hh"
+#include "nix/expr/parser-state.hh"

 // Bison seems to have difficulty growing the parser stack when using C++ with
 // a custom location type. This undocumented macro tells Bison that our
@ -514,7 +514,7 @@ formal

 %%

-#include "eval.hh"
+#include "nix/expr/eval.hh"


 namespace nix {
--- a/src/libexpr/paths.cc
+++ b/src/libexpr/paths.cc
@ -1,5 +1,5 @@
-#include "store-api.hh"
-#include "eval.hh"
+#include "nix/store/store-api.hh"
+#include "nix/expr/eval.hh"

 namespace nix {

--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@ -1,19 +1,19 @@
-#include "derivations.hh"
-#include "downstream-placeholder.hh"
-#include "eval-inline.hh"
-#include "eval.hh"
-#include "eval-settings.hh"
-#include "gc-small-vector.hh"
-#include "json-to-value.hh"
-#include "names.hh"
-#include "path-references.hh"
-#include "store-api.hh"
-#include "util.hh"
-#include "processes.hh"
-#include "value-to-json.hh"
-#include "value-to-xml.hh"
-#include "primops.hh"
-#include "fetch-to-store.hh"
+#include "nix/store/derivations.hh"
+#include "nix/store/downstream-placeholder.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/expr/eval.hh"
+#include "nix/expr/eval-settings.hh"
+#include "nix/expr/gc-small-vector.hh"
+#include "nix/expr/json-to-value.hh"
+#include "nix/store/names.hh"
+#include "nix/store/path-references.hh"
+#include "nix/store/store-api.hh"
+#include "nix/util/util.hh"
+#include "nix/util/processes.hh"
+#include "nix/expr/value-to-json.hh"
+#include "nix/expr/value-to-xml.hh"
+#include "nix/expr/primops.hh"
+#include "nix/fetchers/fetch-to-store.hh"

 #include <boost/container/small_vector.hpp>
 #include <nlohmann/json.hpp>
@ -4669,7 +4669,7 @@ RegisterPrimOp::RegisterPrimOp(PrimOp && primOp)
 }


-void EvalState::createBaseEnv()
+void EvalState::createBaseEnv(const EvalSettings & evalSettings)
 {
    baseEnv.up = 0;

@ -4928,6 +4928,12 @@ void EvalState::createBaseEnv()
                addPrimOp(std::move(primOpAdjusted));
            }

+    for (auto & primOp : evalSettings.extraPrimOps) {
+        auto primOpAdjusted = primOp;
+        primOpAdjusted.arity = std::max(primOp.args.size(), primOp.arity);
+        addPrimOp(std::move(primOpAdjusted));
+    }
+
    /* Add a wrapper around the derivation primop that computes the
       `drvPath' and `outPath' attributes lazily.

--- a/src/libexpr/primops/context.cc
+++ b/src/libexpr/primops/context.cc
@ -1,7 +1,7 @@
-#include "primops.hh"
-#include "eval-inline.hh"
-#include "derivations.hh"
-#include "store-api.hh"
+#include "nix/expr/primops.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/store/derivations.hh"
+#include "nix/store/store-api.hh"

 namespace nix {

--- a/src/libexpr/primops/fetchClosure.cc
+++ b/src/libexpr/primops/fetchClosure.cc
@ -1,8 +1,8 @@
-#include "primops.hh"
-#include "store-api.hh"
-#include "realisation.hh"
-#include "make-content-addressed.hh"
-#include "url.hh"
+#include "nix/expr/primops.hh"
+#include "nix/store/store-api.hh"
+#include "nix/store/realisation.hh"
+#include "nix/store/make-content-addressed.hh"
+#include "nix/util/url.hh"

 namespace nix {

--- a/src/libexpr/primops/fetchMercurial.cc
+++ b/src/libexpr/primops/fetchMercurial.cc
@ -1,10 +1,10 @@
-#include "primops.hh"
-#include "eval-inline.hh"
-#include "eval-settings.hh"
-#include "store-api.hh"
-#include "fetchers.hh"
-#include "url.hh"
-#include "url-parts.hh"
+#include "nix/expr/primops.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/expr/eval-settings.hh"
+#include "nix/store/store-api.hh"
+#include "nix/fetchers/fetchers.hh"
+#include "nix/util/url.hh"
+#include "nix/util/url-parts.hh"

 namespace nix {

--- a/src/libexpr/primops/fetchTree.cc
+++ b/src/libexpr/primops/fetchTree.cc
@ -1,16 +1,16 @@
-#include "attrs.hh"
-#include "primops.hh"
-#include "eval-inline.hh"
-#include "eval-settings.hh"
-#include "store-api.hh"
-#include "fetchers.hh"
-#include "filetransfer.hh"
-#include "registry.hh"
-#include "tarball.hh"
-#include "url.hh"
-#include "value-to-json.hh"
-#include "fetch-to-store.hh"
-#include "mounted-source-accessor.hh"
+#include "nix/fetchers/attrs.hh"
+#include "nix/expr/primops.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/expr/eval-settings.hh"
+#include "nix/store/store-api.hh"
+#include "nix/fetchers/fetchers.hh"
+#include "nix/store/filetransfer.hh"
+#include "nix/fetchers/registry.hh"
+#include "nix/fetchers/tarball.hh"
+#include "nix/util/url.hh"
+#include "nix/expr/value-to-json.hh"
+#include "nix/fetchers/fetch-to-store.hh"
+#include "nix/util/mounted-source-accessor.hh"

 #include <nlohmann/json.hpp>

--- a/src/libexpr/primops/fromTOML.cc
+++ b/src/libexpr/primops/fromTOML.cc
@ -1,5 +1,5 @@
-#include "primops.hh"
-#include "eval-inline.hh"
+#include "nix/expr/primops.hh"
+#include "nix/expr/eval-inline.hh"

 #include <sstream>

--- a/src/libexpr/print-ambiguous.cc
+++ b/src/libexpr/print-ambiguous.cc
@ -1,7 +1,7 @@
-#include "print-ambiguous.hh"
-#include "print.hh"
-#include "signals.hh"
-#include "eval.hh"
+#include "nix/expr/print-ambiguous.hh"
+#include "nix/expr/print.hh"
+#include "nix/util/signals.hh"
+#include "nix/expr/eval.hh"

 namespace nix {

--- a/src/libexpr/print.cc
+++ b/src/libexpr/print.cc
@ -2,13 +2,13 @@
 #include <unordered_set>
 #include <sstream>

-#include "print.hh"
-#include "ansicolor.hh"
-#include "signals.hh"
-#include "store-api.hh"
-#include "terminal.hh"
-#include "english.hh"
-#include "eval.hh"
+#include "nix/expr/print.hh"
+#include "nix/util/ansicolor.hh"
+#include "nix/util/signals.hh"
+#include "nix/store/store-api.hh"
+#include "nix/util/terminal.hh"
+#include "nix/util/english.hh"
+#include "nix/expr/eval.hh"

 namespace nix {

--- a/src/libexpr/search-path.cc
+++ b/src/libexpr/search-path.cc
@ -1,4 +1,4 @@
-#include "search-path.hh"
+#include "nix/expr/search-path.hh"

 namespace nix {

--- a/src/libexpr/value-to-json.cc
+++ b/src/libexpr/value-to-json.cc
@ -1,7 +1,7 @@
-#include "value-to-json.hh"
-#include "eval-inline.hh"
-#include "store-api.hh"
-#include "signals.hh"
+#include "nix/expr/value-to-json.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/store/store-api.hh"
+#include "nix/util/signals.hh"

 #include <cstdlib>
 #include <iomanip>
--- a/src/libexpr/value-to-xml.cc
+++ b/src/libexpr/value-to-xml.cc
@ -1,7 +1,7 @@
-#include "value-to-xml.hh"
-#include "xml-writer.hh"
-#include "eval-inline.hh"
-#include "signals.hh"
+#include "nix/expr/value-to-xml.hh"
+#include "nix/util/xml-writer.hh"
+#include "nix/expr/eval-inline.hh"
+#include "nix/util/signals.hh"

 #include <cstdlib>

--- a/src/libexpr/value/context.cc
+++ b/src/libexpr/value/context.cc
@ -1,5 +1,5 @@
-#include "util.hh"
-#include "value/context.hh"
+#include "nix/util/util.hh"
+#include "nix/expr/value/context.hh"

 #include <optional>