diff --git a/src/blob/mod.rs b/src/blob/mod.rs
index 090f06f..dd41577 100644
--- a/src/blob/mod.rs
+++ b/src/blob/mod.rs
@@ -19,10 +19,3 @@ pub struct Blob {
     tpe: BlobType,
     id: Id,
 }
-
-#[derive(Debug, Clone, Constructor)]
-pub struct BlobInformation {
-    blob: Blob,
-    offset: u32,
-    length: u32,
-}
diff --git a/src/commands/cat.rs b/src/commands/cat.rs
index ebd8caa..91d7cfb 100644
--- a/src/commands/cat.rs
+++ b/src/commands/cat.rs
@@ -3,7 +3,7 @@ use clap::Parser;
 
 use crate::backend::{FileType, MapResult, ReadBackend};
 use crate::id::Id;
-use crate::index::{indexfiles::AllIndexFiles, ReadIndex};
+use crate::index::{AllIndexFiles, BoomIndex, ReadIndex};
 
 #[derive(Parser)]
 pub(super) struct Opts {
@@ -19,7 +19,8 @@ pub(super) fn execute(be: &impl ReadBackend, dbe: &impl ReadBackend, opts: Opts)
         // special treatment for catingg blobs: read the index and use it to locate the blob
         "blob" => {
             let id = Id::from_hex(&opts.id)?;
-            let dec = AllIndexFiles::new(be.clone())
+            let index = BoomIndex::from_iter(AllIndexFiles::new(be.clone()).into_iter());
+            let dec = index
                 .get_id(&id)
                 .ok_or(anyhow!("blob not found in index"))?
                 .read_data(be)?;
diff --git a/src/commands/list.rs b/src/commands/list.rs
index 5a0ce89..afe0c04 100644
--- a/src/commands/list.rs
+++ b/src/commands/list.rs
@@ -15,8 +15,10 @@ pub(super) fn execute(be: &impl ReadBackend, opts: Opts) -> Result<()> {
     let tpe = match opts.tpe.as_str() {
         // special treatment for listing blobs: read the index and display it
         "blobs" => {
-            for ie in AllIndexFiles::new(be.clone()).into_iter() {
-                println!("{:?} {}", ie.tpe(), ie.id().to_hex());
+            for i in AllIndexFiles::new(be.clone()).into_iter() {
+                for blob in i.blobs() {
+                    println!("{:?} {}", blob.tpe(), blob.id().to_hex());
+                }
             }
             return Ok(());
         }
diff --git a/src/index/boom.rs b/src/index/boom.rs
index ef884ad..db3f3a0 100644
--- a/src/index/boom.rs
+++ b/src/index/boom.rs
@@ -1,36 +1,61 @@
 use boomphf::hashmap::BoomHashMap;
 
-use super::{AllIndexFiles, IndexEntry, ReadIndex};
-use crate::backend::ReadBackend;
+use super::{BlobType, IndexEntry, ReadIndex};
 use crate::id::Id;
+use crate::repo::IndexPack;
 
-pub struct BoomIndex(BoomHashMap<Id, IndexEntry>);
-
-impl BoomIndex {
-    pub fn from_all_indexfiles<BE: ReadBackend>(aif: AllIndexFiles<BE>) -> Self {
-        Self::from_iter(aif.into_iter())
-    }
+#[derive(Debug)]
+struct BoomEntry {
+    pack_idx: usize,
+    tpe: BlobType,
+    offset: u32,
+    length: u32,
 }
 
-impl FromIterator<IndexEntry> for BoomIndex {
+pub struct BoomIndex {
+    packs: Vec<Id>,
+    boom: BoomHashMap<Id, BoomEntry>,
+}
+
+impl FromIterator<IndexPack> for BoomIndex {
     fn from_iter<T>(iter: T) -> Self
     where
-        T: IntoIterator<Item = IndexEntry>,
+        T: IntoIterator<Item = IndexPack>,
     {
+        let mut packs = Vec::new();
         let mut ids = Vec::new();
-        let mut ies = Vec::new();
+        let mut bes = Vec::new();
 
-        for ie in iter {
-            ids.push(*ie.id());
-            ies.push(ie);
+        for i in iter {
+            let idx = packs.len();
+            packs.push(*i.id());
+
+            let len = i.blobs().len();
+            ids.reserve(len);
+            bes.reserve(len);
+            for blob in i.blobs() {
+                let be = BoomEntry {
+                    pack_idx: idx,
+                    tpe: *blob.tpe(),
+                    offset: *blob.offset(),
+                    length: *blob.length(),
+                };
+                ids.push(*blob.id());
+                bes.push(be);
+            }
         }
 
-        BoomIndex(BoomHashMap::new(ids, ies))
+        Self {
+            packs,
+            boom: BoomHashMap::new(ids, bes),
+        }
     }
 }
 
 impl ReadIndex for BoomIndex {
     fn get_id(&self, id: &Id) -> Option<IndexEntry> {
-        self.0.get(id).map(IndexEntry::clone)
+        self.boom
+            .get(id)
+            .map(|be| IndexEntry::new(self.packs[be.pack_idx], be.tpe, be.offset, be.length))
     }
 }
diff --git a/src/index/indexfiles.rs b/src/index/indexfiles.rs
index 96dffaa..1b098e1 100644
--- a/src/index/indexfiles.rs
+++ b/src/index/indexfiles.rs
@@ -1,7 +1,5 @@
-use super::{IndexEntry, ReadIndex};
 use crate::backend::{FileType, ReadBackend};
-use crate::id::Id;
-use crate::repo::IndexFile;
+use crate::repo::{IndexFile, IndexPack};
 
 #[derive(Clone)]
 pub struct AllIndexFiles<BE> {
@@ -15,25 +13,14 @@ impl<BE: ReadBackend> AllIndexFiles<BE> {
 }
 
 impl<BE: ReadBackend> AllIndexFiles<BE> {
-    pub fn into_iter(self) -> impl Iterator<Item = IndexEntry> {
+    pub fn into_iter(self) -> impl Iterator<Item = IndexPack> {
         self.be
             .list(FileType::Index)
             .unwrap()
             .into_iter()
             .flat_map(move |id| {
                 let (_, packs) = IndexFile::from_backend(&self.be, id).unwrap().dissolve();
-                packs.into_iter().flat_map(|p| {
-                    let (id, blobs) = p.dissolve();
-                    blobs
-                        .into_iter()
-                        .map(move |b| IndexEntry::from_index_blob(id, b))
-                })
+                packs
             })
     }
 }
-
-impl<BE: ReadBackend> ReadIndex for AllIndexFiles<BE> {
-    fn get_id(&self, id: &Id) -> Option<IndexEntry> {
-        self.clone().into_iter().find(|ie| ie.id() == id)
-    }
-}
diff --git a/src/index/mod.rs b/src/index/mod.rs
index 75e42f6..9ff46a3 100644
--- a/src/index/mod.rs
+++ b/src/index/mod.rs
@@ -1,7 +1,6 @@
 use crate::backend::{FileType, ReadBackend};
-use crate::blob::{Blob, BlobType};
+use crate::blob::BlobType;
 use crate::id::Id;
-use crate::repo::IndexBlob;
 use anyhow::Result;
 use derive_getters::{Dissolve, Getters};
 use derive_more::Constructor;
@@ -16,31 +15,15 @@ pub use indexfiles::*;
 pub struct IndexEntry {
     pack: Id,
     tpe: BlobType,
-    id: Id,
     offset: u32,
     length: u32,
 }
 
 impl IndexEntry {
-    pub fn from_index_blob(pid: Id, ie: IndexBlob) -> Self {
-        Self {
-            pack: pid,
-            tpe: *ie.tpe(),
-            id: *ie.id(),
-            offset: *ie.offset(),
-            length: *ie.length(),
-        }
-    }
-
     /// Get a blob described by IndexEntry from the backend
     pub fn read_data<B: ReadBackend>(&self, be: &B) -> Result<Vec<u8>> {
         Ok(be.read_partial(FileType::Pack, self.pack, self.offset, self.length)?)
     }
-
-    #[inline]
-    pub fn blob(&self) -> Blob {
-        Blob::new(self.tpe, self.id)
-    }
 }
 pub trait ReadIndex {
     fn get_id(&self, id: &Id) -> Option<IndexEntry>;