diff --git a/devtools/hackdoc/source/source.go b/devtools/hackdoc/source/source.go
index a79a920..73d8990 100644
--- a/devtools/hackdoc/source/source.go
+++ b/devtools/hackdoc/source/source.go
@@ -1,10 +1,36 @@
 package source
 
-type Source interface {
-	IsFile(path string) (bool, error)
-	ReadFile(path string) ([]byte, error)
-	IsDirectory(path string) (bool, error)
+import "context"
 
-	CacheSet(dependencies []string, key string, value interface{})
-	CacheGet(key string) interface{}
+var (
+	FlagGitwebURLPattern = "https://gerrit.hackerspace.pl/plugins/gitiles/hscloud/+/%s/%s"
+)
+
+type Source interface {
+	IsFile(ctx context.Context, path string) (bool, error)
+	ReadFile(ctx context.Context, path string) ([]byte, error)
+	IsDirectory(ctx context.Context, path string) (bool, error)
+	WebLinks(fpath string) []WebLink
+}
+
+type WebLink struct {
+	Kind      string
+	LinkLabel string
+	LinkURL   string
+}
+
+type SourceProvider interface {
+	Source(ctx context.Context, rev string) (Source, error)
+}
+
+type singleRefProvider struct {
+	source Source
+}
+
+func (s *singleRefProvider) Source(ctx context.Context, rev string) (Source, error) {
+	return s.source, nil
+}
+
+func NewSingleRefProvider(s Source) SourceProvider {
+	return &singleRefProvider{s}
 }