diff --git a/lib/go/camli/index/index_test.go b/lib/go/camli/index/index_test.go
index f157a0c1d..9d944f277 100644
--- a/lib/go/camli/index/index_test.go
+++ b/lib/go/camli/index/index_test.go
@@ -17,9 +17,90 @@ limitations under the License.
 package index
 
 import (
+	"fmt"
 	"testing"
+
+	"camli/blobref"
+	"camli/jsonsign"
+	"camli/schema"
+	"camli/test"
 )
 
+type IndexDeps struct {
+	Index *Index
+
+	// Following three needed for signing:
+	PublicKeyFetcher *test.Fetcher
+	EntityFetcher    jsonsign.EntityFetcher // fetching decrypted openpgp entities
+	SignerBlobRef    *blobref.BlobRef
+}
+
+func (id *IndexDeps) uploadAndSignMap(m map[string]interface{}) *blobref.BlobRef {
+	m["camliSigner"] = id.SignerBlobRef
+	unsigned, err := schema.MapToCamliJson(m)
+	if err != nil {
+		panic("uploadAndSignMap: " + err.String())
+	}
+	sr := &jsonsign.SignRequest{
+		UnsignedJson:  unsigned,
+		Fetcher:       id.PublicKeyFetcher,
+		EntityFetcher: id.EntityFetcher,
+	}
+	signed, err := sr.Sign()
+	if err != nil {
+		panic("problem signing: " + err.String())
+	}
+	tb := &test.Blob{Contents: signed}
+	_, err = id.Index.ReceiveBlob(tb.BlobRef(), tb.Reader())
+	if err != nil {
+		panic(fmt.Sprintf("problem indexing blob: %v\nblob was:\n%s", err, signed))
+	}
+	return tb.BlobRef()
+}
+
+// NewPermanode creates (& signs) a new permanode and adds it
+// to the index, returning its blobref.
+func (id *IndexDeps) NewPermanode() *blobref.BlobRef {
+	unsigned := schema.NewUnsignedPermanode()
+	return id.uploadAndSignMap(unsigned)
+}
+
+func NewIndexDeps() *IndexDeps {
+	secretRingFile := "../../../../lib/go/camli/jsonsign/testdata/test-secring.gpg"
+	pubKey := &test.Blob{Contents: `-----BEGIN PGP PUBLIC KEY BLOCK-----
+
+xsBNBEzgoVsBCAC/56aEJ9BNIGV9FVP+WzenTAkg12k86YqlwJVAB/VwdMlyXxvi
+bCT1RVRfnYxscs14LLfcMWF3zMucw16mLlJCBSLvbZ0jn4h+/8vK5WuAdjw2YzLs
+WtBcjWn3lV6tb4RJz5gtD/o1w8VWxwAnAVIWZntKAWmkcChCRgdUeWso76+plxE5
+aRYBJqdT1mctGqNEISd/WYPMgwnWXQsVi3x4z1dYu2tD9uO1dkAff12z1kyZQIBQ
+rexKYRRRh9IKAayD4kgS0wdlULjBU98aeEaMz1ckuB46DX3lAYqmmTEL/Rl9cOI0
+Enpn/oOOfYFa5h0AFndZd1blMvruXfdAobjVABEBAAE=
+=28/7
+-----END PGP PUBLIC KEY BLOCK-----`}
+
+	id := &IndexDeps{
+		Index:            newMemoryIndex(),
+		PublicKeyFetcher: new(test.Fetcher),
+		EntityFetcher: &jsonsign.CachingEntityFetcher{
+			Fetcher: &jsonsign.FileEntityFetcher{File: secretRingFile},
+		},
+		SignerBlobRef: pubKey.BlobRef(),
+	}
+	// Add dev-camput's test key public key, keyid 26F5ABDA,
+	// blobref sha1-ad87ca5c78bd0ce1195c46f7c98e6025abbaf007
+	if id.SignerBlobRef.String() != "sha1-ad87ca5c78bd0ce1195c46f7c98e6025abbaf007" {
+		panic("unexpected signer blobref")
+	}
+	id.PublicKeyFetcher.AddBlob(pubKey)
+	return id
+}
+
+func TestIndexPopulation(t *testing.T) {
+	id := NewIndexDeps()
+	pn := id.NewPermanode()
+	t.Logf("uploaded permanode %q", pn)
+}
+
 func TestReverseTimeString(t *testing.T) {
 	in := "2011-11-27T01:23:45Z"
 	got := reverseTimeString(in)
diff --git a/lib/go/camli/index/memindex.go b/lib/go/camli/index/memindex.go
index fce8b3317..f2102191d 100644
--- a/lib/go/camli/index/memindex.go
+++ b/lib/go/camli/index/memindex.go
@@ -32,13 +32,14 @@ func init() {
 		blobserver.StorageConstructor(newMemoryIndexFromConfig))
 }
 
-func newMemoryIndexFromConfig(ld blobserver.Loader, config jsonconfig.Obj) (blobserver.Storage, os.Error) {
-	blobPrefix := config.RequiredString("blobSource")
-
+func newMemoryIndex() *Index {
 	db := memdb.New(nil)
 	memStorage := &memKeys{db: db}
+	return New(memStorage)
+}
 
-	ix := New(memStorage)
+func newMemoryIndexFromConfig(ld blobserver.Loader, config jsonconfig.Obj) (blobserver.Storage, os.Error) {
+	blobPrefix := config.RequiredString("blobSource")
 	if err := config.Validate(); err != nil {
 		return nil, err
 	}
@@ -46,6 +47,8 @@ func newMemoryIndexFromConfig(ld blobserver.Loader, config jsonconfig.Obj) (blob
 	if err != nil {
 		return nil, err
 	}
+
+	ix := newMemoryIndex()
 	ix.BlobSource = sto
 
 	// Good enough, for now: