--- a/pkg/imports/fm.go	Fri Feb 07 12:35:11 2020 +0100
+++ b/pkg/imports/fm.go	Fri Feb 07 19:38:48 2020 +0100
@@ -62,10 +62,11 @@
 	// Constructor returning pointer to struct
 	// representing featuretype's properties
 	newProps func() interface{},
+	// Construct pointer to featuretype from given pointSlice and properties
+	newFeat func(pointSlice, interface{}) interface{},
 ) (
-	// Elements can be converted to []interface{}{p, fp} with
-	// p being a pointSlice and fp of the type of argument props.
-	fms [][]interface{},
+	// Slice of features to be converted to featuretypes type
+	fms []interface{},
 	epsg int,
 	err error,
 ) {
@@ -147,7 +148,7 @@
 					return err
 				}
 
-				f := []interface{}{p, props}
+				f := newFeat(p, props)
 				fms = append(fms, f)
 			default:
 				unsupported[feature.Geometry.Type]++

--- a/pkg/imports/fm_bcnlat.go	Fri Feb 07 12:35:11 2020 +0100
+++ b/pkg/imports/fm_bcnlat.go	Fri Feb 07 19:38:48 2020 +0100
@@ -76,6 +76,11 @@
 	Dirimp      *string `json:"ienc_dirimp,omitempty"`
 }
 
+type bcnlatFeaturetype struct {
+	geom  pointSlice
+	props *bcnlatProperties
+}
+
 const (
 	insertBCNLATSQL = `
 with a as (
@@ -136,6 +141,9 @@
 		feedback,
 		fm.FairwayMarks,
 		func() interface{} { return new(bcnlatProperties) },
+		func(p pointSlice, props interface{}) interface{} {
+			return &bcnlatFeaturetype{p, props.(*bcnlatProperties)}
+		},
 	)
 	if err != nil {
 		return nil, err
@@ -155,24 +163,24 @@
 
 	savepoint := Savepoint(ctx, tx, "feature")
 
-	var outsideOrDup int
-
-	var features int
+	var (
+		outsideOrDup int
+		features     int
+	)
 	for _, fm := range fms {
 
-		p := fm[0].(pointSlice)
-		fp := fm[1].(*bcnlatProperties)
+		f := fm.(*bcnlatFeaturetype)
 
 		var catlam sql.NullInt64
-		if fp.HydroCatlam != nil {
-			catlam = sql.NullInt64{Int64: *fp.HydroCatlam, Valid: true}
-		} else if fp.IENCCatlam != nil {
-			catlam = sql.NullInt64{Int64: *fp.IENCCatlam, Valid: true}
+		if f.props.HydroCatlam != nil {
+			catlam = sql.NullInt64{Int64: *f.props.HydroCatlam, Valid: true}
+		} else if f.props.IENCCatlam != nil {
+			catlam = sql.NullInt64{Int64: *f.props.IENCCatlam, Valid: true}
 		}
 
 		var dirimp sql.NullInt64
-		if fp.Dirimp != nil {
-			if value, err := strconv.ParseInt(*fp.Dirimp, 10, 64); err == nil {
+		if f.props.Dirimp != nil {
+			if value, err := strconv.ParseInt(*f.props.Dirimp, 10, 64); err == nil {
 				dirimp = sql.NullInt64{Int64: value, Valid: true}
 			}
 		}
@@ -181,25 +189,25 @@
 		err := savepoint(func() error {
 			err := insertStmt.QueryRowContext(
 				ctx,
-				p.asWKB(),
+				f.geom.asWKB(),
 				epsg,
-				fp.Datsta,
-				fp.Datend,
-				fp.Persta,
-				fp.Perend,
-				fp.Objnam,
-				fp.Nobjnm,
-				fp.Inform,
-				fp.Ninfom,
-				fp.Scamin,
-				fp.Picrep,
-				fp.Txtdsc,
-				fp.Sordat,
-				fp.Sorind,
-				fp.Colour,
-				fp.Colpat,
-				fp.Condtn,
-				fp.Bcnshp,
+				f.props.Datsta,
+				f.props.Datend,
+				f.props.Persta,
+				f.props.Perend,
+				f.props.Objnam,
+				f.props.Nobjnm,
+				f.props.Inform,
+				f.props.Ninfom,
+				f.props.Scamin,
+				f.props.Picrep,
+				f.props.Txtdsc,
+				f.props.Sordat,
+				f.props.Sorind,
+				f.props.Colour,
+				f.props.Colpat,
+				f.props.Condtn,
+				f.props.Bcnshp,
 				catlam,
 				dirimp,
 			).Scan(&fmid)