diff --git a/NOTICE b/NOTICE
index 4e9c1a6..c6c4e38 100644
--- a/NOTICE
+++ b/NOTICE
@@ -5,9 +5,13 @@ This project includes software derived from the following project:
 
 Project: e2b infra
 Repository: https://github.com/e2b-dev/infra
-Original directory: packages/envd
 
-The envd/ directory and proto/envd/*.proto files in this repository contains code derived from the above project and is licensed under the Apache License Version 2.0.
+The following files and directories in this repository contain code derived from the above project and are licensed under the Apache License Version 2.0:
+
+- envd/
+- proto/envd/*.proto
+- internal/snapshot/
+- internal/uffd/
 
 Modifications to this code were made by M/S Omukk.
 
diff --git a/internal/snapshot/header.go b/internal/snapshot/header.go
index 3083af7..e679529 100644
--- a/internal/snapshot/header.go
+++ b/internal/snapshot/header.go
@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: Apache-2.0
+// Modifications by M/S Omukk
+
 // Package snapshot implements snapshot storage, header-based memory mapping,
 // and memory file processing for Firecracker VM snapshots.
 //
@@ -6,8 +9,6 @@
 // previous generation. A Header contains a sorted list of BuildMap entries
 // that together cover the entire memory address space, with each entry
 // pointing to a specific generation's diff file.
-//
-// Inspired by e2b's snapshot system (Apache 2.0, modified by Omukk).
 package snapshot
 
 import (
diff --git a/internal/snapshot/mapping.go b/internal/snapshot/mapping.go
index f39a175..8451518 100644
--- a/internal/snapshot/mapping.go
+++ b/internal/snapshot/mapping.go
@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: Apache-2.0
+// Modifications by M/S Omukk
+
 package snapshot
 
 import "github.com/google/uuid"
@@ -6,8 +9,6 @@ import "github.com/google/uuid"
 // a sorted list of BuildMap entries. Consecutive dirty blocks are merged into
 // a single entry. BuildStorageOffset tracks the sequential position in the
 // compact diff file.
-//
-// Inspired by e2b's snapshot system (Apache 2.0, modified by Omukk).
 func CreateMapping(buildID uuid.UUID, dirty []bool, blockSize int64) []*BuildMap {
 	var mappings []*BuildMap
 	var runStart int64 = -1
diff --git a/internal/snapshot/memfile.go b/internal/snapshot/memfile.go
index 5ef052f..a0bbc95 100644
--- a/internal/snapshot/memfile.go
+++ b/internal/snapshot/memfile.go
@@ -1,3 +1,6 @@
+// SPDX-License-Identifier: Apache-2.0
+// Modifications by M/S Omukk
+
 package snapshot
 
 import (
diff --git a/internal/uffd/fd.go b/internal/uffd/fd.go
index 1094930..492a520 100644
--- a/internal/uffd/fd.go
+++ b/internal/uffd/fd.go
@@ -1,9 +1,10 @@
+// SPDX-License-Identifier: Apache-2.0
+// Modifications by M/S Omukk
+
 // Package uffd implements a userfaultfd-based memory server for Firecracker
 // snapshot restore. When a VM is restored from a snapshot, instead of loading
 // the entire memory file upfront, the UFFD handler intercepts page faults
 // and serves memory pages on demand from the snapshot's compact diff file.
-//
-// Inspired by e2b's UFFD implementation (Apache 2.0, modified by Omukk).
 package uffd
 
 /*
diff --git a/internal/uffd/region.go b/internal/uffd/region.go
index afe7f14..20b3921 100644
--- a/internal/uffd/region.go
+++ b/internal/uffd/region.go
@@ -1,3 +1,9 @@
+// SPDX-License-Identifier: Apache-2.0
+// Modifications by M/S Omukk
+//
+// Modifications by Omukk (Wrenn Sandbox): merged Region and Mapping into
+// single file, inlined shiftedOffset helper.
+
 package uffd
 
 import "fmt"
diff --git a/internal/uffd/server.go b/internal/uffd/server.go
index 31d8479..7b2e68b 100644
--- a/internal/uffd/server.go
+++ b/internal/uffd/server.go
@@ -1,3 +1,11 @@
+// SPDX-License-Identifier: Apache-2.0
+// Modifications by M/S Omukk
+//
+// Modifications by Omukk (Wrenn Sandbox): replaced errgroup with WaitGroup
+// + semaphore, replaced fdexit abstraction with pipe, integrated with
+// snapshot.Header-based DiffFileSource instead of block.ReadonlyDevice,
+// fixed EAGAIN handling in poll loop.
+
 package uffd
 
 /*