diff --git a/lix/legacy/build-remote.cc b/lix/legacy/build-remote.cc
index a022776a1..2e4b3d15f 100644
--- a/lix/legacy/build-remote.cc
+++ b/lix/legacy/build-remote.cc
@@ -387,7 +387,7 @@ connected:
             // Should hold, because if the feature isn't enabled the set
             // of missing realisations should be empty
             experimentalFeatureSettings.require(Xp::CaDerivations);
-            store->registerDrvOutput(realisation);
+            aio.blockOn(store->registerDrvOutput(realisation));
         }
 
         return 0;
diff --git a/lix/libstore/binary-cache-store.cc b/lix/libstore/binary-cache-store.cc
index c16ce970a..5bbdd74ac 100644
--- a/lix/libstore/binary-cache-store.cc
+++ b/lix/libstore/binary-cache-store.cc
@@ -502,11 +502,15 @@ std::shared_ptr<const Realisation> BinaryCacheStore::queryRealisationUncached(co
     return std::make_shared<const Realisation>(realisation);
 }
 
-void BinaryCacheStore::registerDrvOutput(const Realisation& info) {
+kj::Promise<Result<void>> BinaryCacheStore::registerDrvOutput(const Realisation& info)
+try {
     if (diskCache)
         diskCache->upsertRealisation(getUri(), info);
     auto filePath = realisationsPrefix + "/" + info.id.to_string() + ".doi";
     upsertFile(filePath, info.toJSON().dump(), "application/json");
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
 ref<FSAccessor> BinaryCacheStore::getFSAccessor()
diff --git a/lix/libstore/binary-cache-store.hh b/lix/libstore/binary-cache-store.hh
index efa0bbdd0..9da939b85 100644
--- a/lix/libstore/binary-cache-store.hh
+++ b/lix/libstore/binary-cache-store.hh
@@ -144,7 +144,7 @@ public:
         const StorePathSet & references,
         RepairFlag repair) override;
 
-    void registerDrvOutput(const Realisation & info) override;
+    kj::Promise<Result<void>> registerDrvOutput(const Realisation & info) override;
 
     std::shared_ptr<const Realisation> queryRealisationUncached(const DrvOutput &) override;
 
diff --git a/lix/libstore/build/derivation-goal.cc b/lix/libstore/build/derivation-goal.cc
index fe6cadcf0..020f86725 100644
--- a/lix/libstore/build/derivation-goal.cc
+++ b/lix/libstore/build/derivation-goal.cc
@@ -1192,7 +1192,7 @@ try {
                     );
                 }
                 signRealisation(newRealisation);
-                worker.store.registerDrvOutput(newRealisation);
+                TRY_AWAIT(worker.store.registerDrvOutput(newRealisation));
             }
             outputPaths.insert(realisation.outPath);
             builtOutputs.emplace(outputName, realisation);
@@ -1691,12 +1691,12 @@ try {
                 // derivation, and the output path is valid, but we don't have
                 // its realisation stored (probably because it has been built
                 // without the `ca-derivations` experimental flag).
-                worker.store.registerDrvOutput(
+                TRY_AWAIT(worker.store.registerDrvOutput(
                     Realisation {
                         drvOutput,
                         info.known->path,
                     }
-                );
+                ));
             }
         }
         if (info.known && info.known->isValid())
diff --git a/lix/libstore/build/drv-output-substitution-goal.cc b/lix/libstore/build/drv-output-substitution-goal.cc
index 2fd43d5bc..ad9fd1f90 100644
--- a/lix/libstore/build/drv-output-substitution-goal.cc
+++ b/lix/libstore/build/drv-output-substitution-goal.cc
@@ -141,15 +141,15 @@ try {
 
     if (nrFailed > 0) {
         debug("The output path of the derivation output '%s' could not be substituted", id.to_string());
-        return {WorkResult{
+        co_return WorkResult{
             nrNoSubstituters > 0 || nrIncompleteClosure > 0 ? ecIncompleteClosure : ecFailed,
-        }};
+        };
     }
 
-    worker.store.registerDrvOutput(*outputInfo);
-    return finished();
+    TRY_AWAIT(worker.store.registerDrvOutput(*outputInfo));
+    co_return TRY_AWAIT(finished());
 } catch (...) {
-    return {result::current_exception()};
+    co_return result::current_exception();
 }
 
 kj::Promise<Result<Goal::WorkResult>> DrvOutputSubstitutionGoal::finished() noexcept
diff --git a/lix/libstore/build/local-derivation-goal.cc b/lix/libstore/build/local-derivation-goal.cc
index 58b583ac1..d928efb60 100644
--- a/lix/libstore/build/local-derivation-goal.cc
+++ b/lix/libstore/build/local-derivation-goal.cc
@@ -1151,10 +1151,10 @@ struct RestrictedStore : public virtual IndirectRootStore, public virtual GcStor
         return {result::current_exception()};
     }
 
-    void registerDrvOutput(const Realisation & info) override
+    kj::Promise<Result<void>> registerDrvOutput(const Realisation & info) override
     // XXX: This should probably be allowed as a no-op if the realisation
     // corresponds to an allowed derivation
-    { throw Error("registerDrvOutput"); }
+    try { throw Error("registerDrvOutput"); } catch (...) { return {result::current_exception()}; }
 
     std::shared_ptr<const Realisation> queryRealisationUncached(const DrvOutput & id) override
     // XXX: This should probably be allowed if the realisation corresponds to
@@ -2508,7 +2508,7 @@ try {
             && drv->type().isPure())
         {
             signRealisation(thisRealisation);
-            worker.store.registerDrvOutput(thisRealisation);
+            TRY_AWAIT(worker.store.registerDrvOutput(thisRealisation));
         }
         builtOutputs.emplace(outputName, thisRealisation);
     }
diff --git a/lix/libstore/daemon.cc b/lix/libstore/daemon.cc
index cbfa18912..adee7a528 100644
--- a/lix/libstore/daemon.cc
+++ b/lix/libstore/daemon.cc
@@ -956,11 +956,11 @@ static void performOp(AsyncIoRoot & aio, TunnelLogger * logger, ref<Store> store
         if (GET_PROTOCOL_MINOR(clientVersion) < 31) {
             auto outputId = DrvOutput::parse(readString(from));
             auto outputPath = StorePath(readString(from));
-            store->registerDrvOutput(Realisation{
-                .id = outputId, .outPath = outputPath});
+            aio.blockOn(store->registerDrvOutput(Realisation{
+                .id = outputId, .outPath = outputPath}));
         } else {
             auto realisation = WorkerProto::Serialise<Realisation>::read(*store, rconn);
-            store->registerDrvOutput(realisation);
+            aio.blockOn(store->registerDrvOutput(realisation));
         }
         logger->stopWork();
         break;
diff --git a/lix/libstore/local-store.cc b/lix/libstore/local-store.cc
index eb8333c12..f005a0d08 100644
--- a/lix/libstore/local-store.cc
+++ b/lix/libstore/local-store.cc
@@ -772,67 +772,80 @@ void canonicalisePathMetaData(const Path & path,
 }
 
 
-void LocalStore::registerDrvOutput(const Realisation & info, CheckSigsFlag checkSigs)
-{
+kj::Promise<Result<void>>
+LocalStore::registerDrvOutput(const Realisation & info, CheckSigsFlag checkSigs)
+try {
     experimentalFeatureSettings.require(Xp::CaDerivations);
     if (checkSigs == NoCheckSigs || !realisationIsUntrusted(info))
-        registerDrvOutput(info);
+        TRY_AWAIT(registerDrvOutput(info));
     else
         throw Error("cannot register realisation '%s' because it lacks a signature by a trusted key", info.outPath.to_string());
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
-void LocalStore::registerDrvOutput(const Realisation & info)
-{
+kj::Promise<Result<void>> LocalStore::registerDrvOutput(const Realisation & info)
+try {
     experimentalFeatureSettings.require(Xp::CaDerivations);
-    retrySQLite([&]() {
-        auto state = dbPool.get();
-        if (auto oldR = queryRealisation_(*state, info.id)) {
-            if (info.isCompatibleWith(*oldR)) {
-                auto combinedSignatures = oldR->signatures;
-                combinedSignatures.insert(info.signatures.begin(),
-                    info.signatures.end());
-                state->stmts->UpdateRealisedOutput.use()
-                    (concatStringsSep(" ", combinedSignatures))
+    // NOLINTNEXTLINE(cppcoreguidelines-avoid-capturing-lambda-coroutines)
+    TRY_AWAIT(retrySQLite([&]() -> kj::Promise<Result<void>> {
+        try {
+            auto state = dbPool.get();
+            if (auto oldR = queryRealisation_(*state, info.id)) {
+                if (info.isCompatibleWith(*oldR)) {
+                    auto combinedSignatures = oldR->signatures;
+                    combinedSignatures.insert(info.signatures.begin(),
+                        info.signatures.end());
+                    state->stmts->UpdateRealisedOutput.use()
+                        (concatStringsSep(" ", combinedSignatures))
+                        (info.id.strHash())
+                        (info.id.outputName)
+                        .exec();
+                } else {
+                    throw Error("Trying to register a realisation of '%s', but we already "
+                                "have another one locally.\n"
+                                "Local:  %s\n"
+                                "Remote: %s",
+                        info.id.to_string(),
+                        printStorePath(oldR->outPath),
+                        printStorePath(info.outPath)
+                    );
+                }
+            } else {
+                state->stmts->RegisterRealisedOutput.use()
                     (info.id.strHash())
                     (info.id.outputName)
+                    (printStorePath(info.outPath))
+                    (concatStringsSep(" ", info.signatures))
                     .exec();
-            } else {
-                throw Error("Trying to register a realisation of '%s', but we already "
-                            "have another one locally.\n"
-                            "Local:  %s\n"
-                            "Remote: %s",
-                    info.id.to_string(),
-                    printStorePath(oldR->outPath),
-                    printStorePath(info.outPath)
-                );
             }
-        } else {
-            state->stmts->RegisterRealisedOutput.use()
-                (info.id.strHash())
-                (info.id.outputName)
-                (printStorePath(info.outPath))
-                (concatStringsSep(" ", info.signatures))
-                .exec();
+            for (auto & [outputId, depPath] : info.dependentRealisations) {
+                auto localRealisation = queryRealisationCore_(*state, outputId);
+                if (!localRealisation)
+                    throw Error("unable to register the derivation '%s' as it "
+                                "depends on the non existent '%s'",
+                        info.id.to_string(), outputId.to_string());
+                if (localRealisation->second.outPath != depPath)
+                    throw Error("unable to register the derivation '%s' as it "
+                                "depends on a realisation of '%s' that doesn’t"
+                                "match what we have locally",
+                        info.id.to_string(), outputId.to_string());
+                state->stmts->AddRealisationReference.use()
+                    (info.id.strHash())
+                    (info.id.outputName)
+                    (outputId.strHash())
+                    (outputId.outputName)
+                    .exec();
+            }
+            co_return result::success();
+        } catch (...) {
+            co_return result::current_exception();
         }
-        for (auto & [outputId, depPath] : info.dependentRealisations) {
-            auto localRealisation = queryRealisationCore_(*state, outputId);
-            if (!localRealisation)
-                throw Error("unable to register the derivation '%s' as it "
-                            "depends on the non existent '%s'",
-                    info.id.to_string(), outputId.to_string());
-            if (localRealisation->second.outPath != depPath)
-                throw Error("unable to register the derivation '%s' as it "
-                            "depends on a realisation of '%s' that doesn’t"
-                            "match what we have locally",
-                    info.id.to_string(), outputId.to_string());
-            state->stmts->AddRealisationReference.use()
-                (info.id.strHash())
-                (info.id.outputName)
-                (outputId.strHash())
-                (outputId.outputName)
-                .exec();
-        }
-    }, always_progresses);
+    }));
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
 void LocalStore::cacheDrvOutputMapping(
diff --git a/lix/libstore/local-store.hh b/lix/libstore/local-store.hh
index 0fd2e5037..711793ae7 100644
--- a/lix/libstore/local-store.hh
+++ b/lix/libstore/local-store.hh
@@ -317,8 +317,9 @@ public:
      * Register the store path 'output' as the output named 'outputName' of
      * derivation 'deriver'.
      */
-    void registerDrvOutput(const Realisation & info) override;
-    void registerDrvOutput(const Realisation & info, CheckSigsFlag checkSigs) override;
+    kj::Promise<Result<void>> registerDrvOutput(const Realisation & info) override;
+    kj::Promise<Result<void>>
+    registerDrvOutput(const Realisation & info, CheckSigsFlag checkSigs) override;
     void cacheDrvOutputMapping(
         DBState & state,
         const uint64_t deriver,
diff --git a/lix/libstore/remote-store.cc b/lix/libstore/remote-store.cc
index 653b78f7d..5fa0c2418 100644
--- a/lix/libstore/remote-store.cc
+++ b/lix/libstore/remote-store.cc
@@ -600,8 +600,8 @@ try {
     co_return result::current_exception();
 }
 
-void RemoteStore::registerDrvOutput(const Realisation & info)
-{
+kj::Promise<Result<void>> RemoteStore::registerDrvOutput(const Realisation & info)
+try {
     auto conn(getConnection());
     conn->to << WorkerProto::Op::RegisterDrvOutput;
     if (GET_PROTOCOL_MINOR(conn->daemonVersion) < 31) {
@@ -612,6 +612,9 @@ void RemoteStore::registerDrvOutput(const Realisation & info)
         conn->to << WorkerProto::write(*this, *conn, info);
     }
     conn.processStderr();
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
 std::shared_ptr<const Realisation> RemoteStore::queryRealisationUncached(const DrvOutput & id)
diff --git a/lix/libstore/remote-store.hh b/lix/libstore/remote-store.hh
index a78ece886..b672e0e36 100644
--- a/lix/libstore/remote-store.hh
+++ b/lix/libstore/remote-store.hh
@@ -112,7 +112,7 @@ public:
         const StorePathSet & references,
         RepairFlag repair) override;
 
-    void registerDrvOutput(const Realisation & info) override;
+    kj::Promise<Result<void>> registerDrvOutput(const Realisation & info) override;
 
     std::shared_ptr<const Realisation> queryRealisationUncached(const DrvOutput &) override;
 
diff --git a/lix/libstore/store-api.cc b/lix/libstore/store-api.cc
index 4fc1ada0e..bac4a5158 100644
--- a/lix/libstore/store-api.cc
+++ b/lix/libstore/store-api.cc
@@ -1155,7 +1155,7 @@ try {
         processGraph<Realisation>(
             "copyPaths pool",
             TRY_AWAIT(Realisation::closure(srcStore, toplevelRealisations)),
-            [&](const Realisation & current) -> std::set<Realisation> {
+            [&](AsyncIoRoot & aio, const Realisation & current) -> std::set<Realisation> {
                 std::set<Realisation> children;
                 for (const auto & [drvOutput, _] : current.dependentRealisations) {
                     auto currentChild = srcStore.queryRealisation(drvOutput);
@@ -1168,8 +1168,8 @@ try {
                 }
                 return children;
             },
-            [&](const Realisation& current) -> void {
-                dstStore.registerDrvOutput(current, checkSigs);
+            [&](AsyncIoRoot & aio, const Realisation& current) -> void {
+                aio.blockOn(dstStore.registerDrvOutput(current, checkSigs));
             });
     } catch (MissingExperimentalFeature & e) {
         // Don't fail if the remote doesn't support CA derivations is it might
diff --git a/lix/libstore/store-api.hh b/lix/libstore/store-api.hh
index 104e9219a..416b0bc79 100644
--- a/lix/libstore/store-api.hh
+++ b/lix/libstore/store-api.hh
@@ -589,10 +589,13 @@ public:
      * floating-ca derivations and their dependencies as there's no way to
      * retrieve this information otherwise.
      */
-    virtual void registerDrvOutput(const Realisation & output)
-    { unsupported("registerDrvOutput"); }
-    virtual void registerDrvOutput(const Realisation & output, CheckSigsFlag checkSigs)
-    { return registerDrvOutput(output); }
+    virtual kj::Promise<Result<void>> registerDrvOutput(const Realisation & output)
+    try { unsupported("registerDrvOutput"); } catch (...) { return {result::current_exception()}; }
+    virtual kj::Promise<Result<void>>
+    registerDrvOutput(const Realisation & output, CheckSigsFlag checkSigs)
+    {
+        return registerDrvOutput(output);
+    }
 
     /**
      * Generate a NAR dump of a store path.