diff --git a/db.go b/db.go
index b9fa812..511e297 100644
--- a/db.go
+++ b/db.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"sync"
 
 	"github.com/aws/aws-sdk-go-v2/aws"
 	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
@@ -17,6 +18,8 @@ import (
 // DB is a DynamoDB client.
 type DB struct {
 	client dynamodbiface.DynamoDBAPI
+	// table description cache for LEK inference
+	descs *sync.Map // table name → Description
 }
 
 // New creates a new client with the given configuration.
@@ -32,6 +35,7 @@ func New(cfg aws.Config, options ...func(*dynamodb.Options)) *DB {
 func NewFromIface(client dynamodbiface.DynamoDBAPI) *DB {
 	db := &DB{
 		client: client,
+		descs:  new(sync.Map),
 	}
 	return db
 }
@@ -41,6 +45,17 @@ func (db *DB) Client() dynamodbiface.DynamoDBAPI {
 	return db.client
 }
 
+func (db *DB) loadDesc(name string) (desc Description, ok bool) {
+	if descv, exists := db.descs.Load(name); exists {
+		desc, ok = descv.(Description)
+	}
+	return
+}
+
+func (db *DB) storeDesc(desc Description) {
+	db.descs.Store(desc.Name, desc)
+}
+
 // ListTables is a request to list tables.
 // See: http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_ListTables.html
 type ListTables struct {
diff --git a/describetable.go b/describetable.go
index 4c295ca..afbdacf 100644
--- a/describetable.go
+++ b/describetable.go
@@ -268,7 +268,7 @@ func (dt *DescribeTable) Run(ctx context.Context) (Description, error) {
 	}
 
 	desc := newDescription(result.Table)
-	dt.table.desc.Store(desc)
+	dt.table.db.storeDesc(desc)
 	return desc, nil
 }
 
diff --git a/scan_test.go b/scan_test.go
index de2dcc9..c25622b 100644
--- a/scan_test.go
+++ b/scan_test.go
@@ -3,6 +3,7 @@ package dynamo
 import (
 	"context"
 	"reflect"
+	"sync"
 	"testing"
 	"time"
 )
@@ -176,7 +177,12 @@ func TestScanMagicLEK(t *testing.T) {
 	if testDB == nil {
 		t.Skip(offlineSkipMsg)
 	}
-	table := testDB.Table(testTableWidgets)
+
+	testDB0 := *testDB
+	testDB0.descs = new(sync.Map)
+	freshTestDB := &testDB0
+
+	table := freshTestDB.Table(testTableWidgets)
 	ctx := context.Background()
 
 	widgets := []interface{}{
diff --git a/table.go b/table.go
index 5faffdb..056e991 100644
--- a/table.go
+++ b/table.go
@@ -3,7 +3,6 @@ package dynamo
 import (
 	"context"
 	"fmt"
-	"sync/atomic"
 	"time"
 
 	"github.com/aws/aws-sdk-go-v2/service/dynamodb"
@@ -33,8 +32,6 @@ const (
 type Table struct {
 	name string
 	db   *DB
-	// desc is this table's cached description, used for inferring keys
-	desc *atomic.Value // Description
 }
 
 // Table returns a Table handle specified by name.
@@ -42,7 +39,6 @@ func (db *DB) Table(name string) Table {
 	return Table{
 		name: name,
 		db:   db,
-		desc: new(atomic.Value),
 	}
 }
 
@@ -119,7 +115,8 @@ func (table Table) primaryKeys(ctx context.Context, lek, esk Item, index string)
 	// now we're forced to call DescribeTable
 
 	// do we have a description cached?
-	if desc, ok := table.desc.Load().(Description); ok {
+
+	if desc, ok := table.db.loadDesc(table.name); ok {
 		keys := desc.keys(index)
 		if keys != nil {
 			return keys, nil