diff --git a/pkg/mongo/mongo.go b/pkg/mongo/mongo.go
index 0d0af80..0126eb9 100644
--- a/pkg/mongo/mongo.go
+++ b/pkg/mongo/mongo.go
@@ -17,7 +17,18 @@ func GlobalTimeout(ctx context.Context) context.Context {
 	return ctx
 }
 
-func Initialize(ctx context.Context, uri string, opts *mongoOpt.ClientOptions) (*mongo.Collection, error) {
+type InitializeOptions struct {
+	MaxPoolSize        uint64
+	CapSizeBytes       int64
+	ExpireAfterSeconds int64
+}
+
+func Initialize(ctx context.Context, uri string, opt *InitializeOptions) (*mongo.Collection, error) {
+	collectionName := "logs"
+	if opt == nil {
+		opt = &InitializeOptions{}
+	}
+
 	uriParsed, err := url.ParseRequestURI(uri)
 	if err != nil {
 		return nil, fmt.Errorf("parsing URI for database name: %w", err)
@@ -28,7 +39,7 @@ func Initialize(ctx context.Context, uri string, opts *mongoOpt.ClientOptions) (
 		return nil, fmt.Errorf("URI must include database name (as database to authenticate against)")
 	}
 
-	dbOpt := attachMetrics(opts).ApplyURI(uri)
+	dbOpt := attachMetrics(mongoOpt.Client()).ApplyURI(uri).SetMaxPoolSize(opt.MaxPoolSize)
 
 	dbClient, err := mongo.Connect(GlobalTimeout(ctx), dbOpt)
 	if err != nil {
@@ -39,7 +50,19 @@ func Initialize(ctx context.Context, uri string, opts *mongoOpt.ClientOptions) (
 		return nil, fmt.Errorf("first ping to database: %w", err)
 	}
 
-	col := dbClient.Database(uriParsed.Path).Collection("logs")
+	db := dbClient.Database(uriParsed.Path)
+
+	capped := opt.CapSizeBytes > 0
+
+	if err := db.CreateCollection(GlobalTimeout(ctx), collectionName, &mongoOpt.CreateCollectionOptions{
+		Capped:             &capped,
+		SizeInBytes:        &opt.CapSizeBytes,
+		ExpireAfterSeconds: &opt.ExpireAfterSeconds,
+	}); err != nil {
+		return nil, fmt.Errorf("initializing collection")
+	}
+
+	col := db.Collection(collectionName)
 
 	if err := InitializeIndexes(GlobalTimeout(ctx), col); err != nil {
 		return nil, fmt.Errorf("initializing indexes: %w", err)
diff --git a/pkg/watcher/app.go b/pkg/watcher/app.go
index 67d99ab..5947eda 100644
--- a/pkg/watcher/app.go
+++ b/pkg/watcher/app.go
@@ -14,7 +14,6 @@ import (
 	"git.k-space.ee/k-space/logmower-shipper/pkg/util"
 	"github.com/fsnotify/fsnotify"
 	"github.com/urfave/cli/v2"
-	mongoOpt "go.mongodb.org/mongo-driver/mongo/options"
 )
 
 var App = &cli.App{
@@ -27,20 +26,22 @@ var App = &cli.App{
 	Flags: []cli.Flag{
 		// in Action
 		&cli.StringFlag{Name: "log-directory", Usage: "Directory to watch for logs", Value: "/var/log/containers"},
-		&cli.Uint64Flag{Name: "max-connection-pool-size", EnvVars: []string{"MAX_CONNECTION_POOL_SIZE"}, Value: 1, Usage: "Max MongoDB connection pool size"},
+		&cli.Uint64Flag{Category: "mongo", Name: "max-connection-pool-size", EnvVars: []string{"MAX_CONNECTION_POOL_SIZE"}, Value: 1, Usage: "Max MongoDB connection pool size"},
+		&cli.Int64Flag{Category: "mongo", Name: "max-collection-size", EnvVars: []string{"MAX_COLLECTION_SIZE"}, Usage: "MongoDB collection size limit in bytes"},
+		&cli.Int64Flag{Category: "mongo", Name: "max-record-retention", EnvVars: []string{"MAX_RECORD_RETENTION"}, Usage: "Record retention in seconds"},
+		&cli.StringFlag{Category: "mongo", Name: "mongo-uri", EnvVars: []string{"MONGODB_URI"}, Usage: "mongodb://foo:bar@host:27017/database", Required: true},
 		// in Before
-		&cli.BoolFlag{Name: "simulate", Aliases: []string{"dry-run"}, Usage: "Do not write to database"},
+		&cli.BoolFlag{Category: "mongo", Name: "simulate", Aliases: []string{"dry-run"}, Usage: "Writes to database are simulate as successful"},
 		&cli.IntFlag{Name: "max-record-size", EnvVars: []string{"MAX_RECORD_SIZE"}, Value: 128 * 1024, Usage: "Maximum record size in bytes"},
 		&cli.IntFlag{Name: "bulk-insertion-size", EnvVars: []string{"BULK_INSERTION_SIZE"}, Value: 1000, Usage: "MongoDB bulk insertion size in records"},
 		&cli.IntFlag{Name: "max-upload-queue-size", EnvVars: []string{"MAX_UPLOAD_QUEUE_SIZE"}, Value: 1024, Usage: "Max upload queue size (before batching) in records"},
-		//
-		//TODO: &cli.BoolFlag{Name: "heuristic-normalize-log-level", Usage: "Normalize log.level values to Syslog defined keywords", Value: false},
-		//TODO: &cli.BoolFlag{Name: "heuristic-parse-json", Usage: "Attempt automatically unwrapping JSON records", Value: false},
+
+		// TODO: &cli.BoolFlag{Category: "parsing", Name: "heuristic-normalize-log-level", Usage: "Normalize log.level values to Syslog defined keywords", Value: false},
+		// TODO: &cli.BoolFlag{Category: "parsing", Name: "heuristic-parse-json", Usage: "Attempt automatically unwrapping JSON records", Value: false},
 
 		&cli.StringSliceFlag{Category: "selectors", Name: "namespace", EnvVars: []string{"NAMESPACE"}, Usage: "whitelist filter for filenames"},
 		&cli.StringSliceFlag{Category: "selectors", Name: "exclude-pod-prefixes", EnvVars: []string{"EXCLUDE_POD_PREFIXES"}, Usage: "blacklist filter for filenames", Value: cli.NewStringSlice("logmower-")},
 		//
-		&cli.StringFlag{Category: "secrets", Name: "mongo-uri", EnvVars: []string{"MONGODB_URI"}, Usage: "mongodb://foo:bar@host:27017/database", Required: true},
 	},
 	Before: func(ctx *cli.Context) error {
 		sender.Simulate = ctx.Bool("simulate")
@@ -60,8 +61,11 @@ var App = &cli.App{
 
 		log.Printf("%s %s starting", ctx.App.Name, ctx.App.Version)
 
-		db, err := m.Initialize(ctx.Context, ctx.String("mongo-uri"), mongoOpt.Client().
-			SetMaxPoolSize(ctx.Uint64("max-connection-pool-size")))
+		db, err := m.Initialize(ctx.Context, ctx.String("mongo-uri"), &m.InitializeOptions{
+			MaxPoolSize:        ctx.Uint64("max-connection-pool-size"),
+			CapSizeBytes:       ctx.Int64("max-collection-size"),
+			ExpireAfterSeconds: ctx.Int64("max-record-retention"),
+		})
 		if err != nil {
 			return fmt.Errorf("initializing database connection: %w", err)
 		}
@@ -95,7 +99,6 @@ var App = &cli.App{
 						continue
 					}
 
-					// TODO: #1: || if not in filterset
 					kubeInfo, ok := util.ParseLogFilename(event.Name)
 					if !ok {
 						promWatcherFilesSkipped.Add(1)