diff --git a/cmd/icingadb/main.go b/cmd/icingadb/main.go
index 857c8379..aabecd10 100644
--- a/cmd/icingadb/main.go
+++ b/cmd/icingadb/main.go
@@ -2,19 +2,15 @@ package main
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"github.com/icinga/icingadb/internal/command"
 	"github.com/icinga/icingadb/pkg/contracts"
-	"github.com/icinga/icingadb/pkg/flatten"
 	"github.com/icinga/icingadb/pkg/icingadb"
 	"github.com/icinga/icingadb/pkg/icingadb/history"
 	v1 "github.com/icinga/icingadb/pkg/icingadb/v1"
 	"github.com/icinga/icingadb/pkg/icingaredis"
-	"github.com/icinga/icingadb/pkg/utils"
 	"github.com/pkg/errors"
 	"golang.org/x/sync/errgroup"
-	"runtime"
 )
 
 func main() {
@@ -55,70 +51,6 @@ func main() {
 				go func() {
 					g, synctx := errgroup.WithContext(hactx)
 
-					g.Go(func() error {
-						return nil
-						// TODO(el). This code is a draft for trying to synchronize customvar_flat from the customvar
-						// delta, which actually doesn't really make sense, since both synchronizations must always be
-						// completed without errors. The synchronization of customar and customvar_flat should only
-						// fetch the desired entities once and multiplex them to the synchronization of customvar and
-						// customvar_flat.
-						delta := s.GetDelta(synctx, v1.NewCustomvar)
-						if err := delta.Wait(); err != nil {
-							return err
-						}
-
-						entities := delta.Create.Entities(synctx)
-						flat := make(chan contracts.Entity, 0)
-
-						cvg, _ := errgroup.WithContext(synctx)
-
-						g.Go(func() error {
-							defer close(flat)
-
-							for i := 0; i < 1<<runtime.NumCPU()*2; i++ {
-								cvg.Go(func() error {
-									for entity := range entities {
-										var value interface{}
-										customvar := entity.(*v1.Customvar)
-										if err := json.Unmarshal([]byte(customvar.Value), &value); err != nil {
-											return err
-										}
-
-										flattened := flatten.Flatten(value, customvar.Name)
-
-										for flatname, flatvalue := range flattened {
-											flatvalue := fmt.Sprintf("%v", flatvalue)
-											flat <- &v1.CustomvarFlat{
-												CustomvarMeta: v1.CustomvarMeta{
-													EntityWithoutChecksum: v1.EntityWithoutChecksum{
-														IdMeta: v1.IdMeta{
-															// TODO(el): Schema comment is wrong.
-															// Without customvar.Id we would produce duplicate keys here.
-															Id: utils.Checksum(customvar.EnvironmentId.String() + customvar.Id.String() + flatname + flatvalue),
-														},
-													},
-													EnvironmentMeta: v1.EnvironmentMeta{
-														EnvironmentId: customvar.EnvironmentId,
-													},
-													CustomvarId: customvar.Id,
-												},
-												Flatname:         flatname,
-												FlatnameChecksum: utils.Checksum(flatname),
-												Flatvalue:        flatvalue,
-											}
-										}
-									}
-
-									return nil
-								})
-							}
-
-							return cvg.Wait()
-						})
-
-						return db.Create(synctx, flat)
-					})
-
 					for _, factoryFunc := range []contracts.EntityFactoryFunc{
 						v1.NewActionUrl,
 						v1.NewCheckcommand,