diff --git a/eliofile/eliofile.go b/eliofile/eliofile.go
index a5b8054..cd51155 100644
--- a/eliofile/eliofile.go
+++ b/eliofile/eliofile.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"strings"
+	"sync"
 	"time"
 
 	"gittea.marcokittel.de/elio/eliotools/tools"
@@ -21,11 +22,14 @@ type ElioDateiFoo struct {
 	process      ElioHandleFunc
 	lookUpDir    string
 	processedDir string
+	mu           sync.RWMutex
+	haveDone     map[string]time.Time
 }
 
 func NewElioDateiFoo(lookUpDir string, process ElioHandleFunc) *ElioDateiFoo {
 	df := ElioDateiFoo{lookUpDir: lookUpDir,
-		process: process,
+		process:  process,
+		haveDone: make(map[string]time.Time),
 	}
 	return &df
 }
@@ -65,6 +69,15 @@ func (f *ElioDateiFoo) ScanCsv() {
 		}
 	}
 	for _, v := range filemap {
-		f.process(v.filename)
+		f.mu.RLock()
+		_, ok := f.haveDone[v.filename]
+		f.mu.RUnlock()
+		if ok {
+			break
+		}
+		f.mu.Lock()
+		f.haveDone[v.filename] = time.Now()
+		f.mu.Unlock()
+		go f.process(v.filename)
 	}
 }