diff --git a/overlay/default.nix b/overlay/default.nix
index a17b84b..6e3c4e0 100644
--- a/overlay/default.nix
+++ b/overlay/default.nix
@@ -168,6 +168,18 @@ in nullPkgs // {
     # Packages from the Nimble flake with adjustments.
     prev.nimPackages.overrideScope' (_: prev': {
 
+      dhall = with prev'; buildNimPackage rec {
+        name = "dhall";
+        version = "0.1.0";
+        src = prev.fetchFromSourcehut {
+          owner = "~ehmry";
+          repo = "dhall-nim";
+          rev = version;
+          hash = "sha256-AhGD/h61Yqiq80woD8bfrvwuTjqCPGYCmUFhK5xFur4=";
+        };
+        buildInputs = [ bigints cbor ];
+      };
+
       genode = prev'.genode.overrideAttrs (attrs: rec {
         version = "20.11.1";
         src = fetchgit {
diff --git a/overlay/eris-patch-hook/default.nix b/overlay/eris-patch-hook/default.nix
index 00568bf..23e756d 100644
--- a/overlay/eris-patch-hook/default.nix
+++ b/overlay/eris-patch-hook/default.nix
@@ -1,10 +1,11 @@
-{ buildNimPackage, patchelf, base32, eris }:
+{ buildNimPackage, patchelf, base32, bigints, cbor, dhall, eris }:
 
 buildNimPackage {
   name = "eris_patch";
-  buildInputs = [ base32 eris ];
+  buildInputs = [ base32 bigints cbor dhall eris ];
   inherit patchelf;
   unpackPhase = "install -D ${./eris_patch.nim} ./src/eris_patch.nim";
+  nimBinOnly = true;
   preConfigure = ''
     cat << EOF > eris_patch.nimble
     bin = @[ "src/eris_patch"]
diff --git a/overlay/eris-patch-hook/eris_patch.nim b/overlay/eris-patch-hook/eris_patch.nim
index 5bed28f..b714074 100644
--- a/overlay/eris-patch-hook/eris_patch.nim
+++ b/overlay/eris-patch-hook/eris_patch.nim
@@ -1,14 +1,25 @@
+import std/[asyncdispatch, deques, json, os, osproc, streams, strutils, tables]
+import dhall/[render, terms]
 import eris
 
-import std/asyncdispatch, std/deques, std/json, std/os, std/osproc, std/streams,
-    std/strutils, std/tables
+proc toDhall(js: JsonNode): Value =
+  case js.kind
+  of JString:
+    result = newValue(js.str)
+  of JObject:
+    result = newRecordLiteral(js.fields.len)
+    for key, val in js.fields.pairs:
+      result.table[key] = val.toDhall
+  else:
+    raiseAssert "unhandled JSON value"
 
 if getEnv("dontErisPatch") != "": quit 0
 
 let
   patchelf = getEnv("ERIS_PATCHELF", "patchelf")
   nixStore = getEnv("NIX_STORE", "/nix/store")
-  manifestSubPath = "nix-support" / "eris-manifest.json"
+  jsonManifestSubPath = "nix-support" / "eris-manifest.json"
+  dhallManifestSubPath = "nix-support" / "eris-manifest.dhall"
 
 proc isElf(path: string): bool =
   var magic: array[4, char]
@@ -27,7 +38,7 @@ var
   failed = false
 for outputName in getEnv("outputs").splitWhitespace:
   let outputRoot = getEnv(outputName)
-  if fileExists(outputRoot / manifestSubPath):
+  if fileExists(outputRoot / jsonManifestSubPath):
     echo "Not running ERIS patch hook again"
     quit 0
   outputManifests[outputRoot] = newJObject()
@@ -103,7 +114,7 @@ proc fileClosure(filePath: string): TableRef[string, string] =
       storePath = p
     if storePath.startsWith nixStore:
       # read the closure manifest of the dependency
-      let manifestPath = storePath / manifestSubPath
+      let manifestPath = storePath / jsonManifestSubPath
       if fileExists(manifestPath):
         let
           manifest = parseFile(manifestPath)
@@ -117,7 +128,7 @@ proc fileClosure(filePath: string): TableRef[string, string] =
     closureCache[filePath] = result
 
 for outputRoot in outputManifests.keys:
-  let manifestPath = outputRoot / manifestSubPath
+  let manifestPath = outputRoot / jsonManifestSubPath
   if fileExists manifestPath: continue
   for filePath in walkDirRec(outputRoot, relative = false):
     # Populate the queue of files to patch
@@ -185,5 +196,8 @@ if failed:
   quit -1
 
 for outputRoot, manifest in outputManifests:
-  createDir(outputRoot / "nix-support")
-  writeFile(outputRoot / manifestSubPath, $manifest)
+  let supportDir = outputRoot / "nix-support"
+  createDir(supportDir)
+  writeFile(outputRoot / jsonManifestSubPath, $manifest)
+  for path, attrs in manifest.pairs:
+    writeFile(supportDir / path.extractFilename & ".eris.dhall", $(attrs.toDhall))