diff --git a/app/graphql/api/v2/context.rb b/app/graphql/api/v2/context.rb
index 080170698..26151a80e 100644
--- a/app/graphql/api/v2/context.rb
+++ b/app/graphql/api/v2/context.rb
@@ -1,13 +1,14 @@
 class API::V2::Context < GraphQL::Query::Context
-  def has_fragment?(name)
-    if self["has_fragment_#{name}"]
-      true
-    else
-      visitor = HasFragment.new(self.query.selected_operation, name)
+  # This method is used to check if a given fragment is used in the given query.
+  # We need that in order to maintain backward compatibility for Types de Champ
+  # that we extended in later iterations of our schema.
+  def has_fragment?(fragment_name)
+    self[:has_fragment] ||= Hash.new do |hash, fragment_name|
+      visitor = HasFragment.new(query.document, fragment_name)
       visitor.visit
-      self["has_fragment_#{name}"] = visitor.found
-      self["has_fragment_#{name}"]
+      hash[fragment_name] = visitor.found
     end
+    self[:has_fragment][fragment_name]
   end
 
   def internal_use?
@@ -36,17 +37,28 @@ class API::V2::Context < GraphQL::Query::Context
     self[:authorized][demarche.id]
   end
 
+  # This is a query AST visitor that we use to check
+  # if a fragment with a given name is used in the given document.
+  # We check for both inline and standalone fragments.
   class HasFragment < GraphQL::Language::Visitor
-    def initialize(document, name)
+    def initialize(document, fragment_name)
       super(document)
-      @name = name.to_s
+      @fragment_name = fragment_name.to_s
       @found = false
     end
 
     attr_reader :found
 
     def on_inline_fragment(node, parent)
-      if node.type.name == @name
+      if node.type.name == @fragment_name
+        @found = true
+      end
+
+      super
+    end
+
+    def on_fragment_definition(node, parent)
+      if node.type.name == @fragment_name
         @found = true
       end
 
diff --git a/spec/graphql/dossier_spec.rb b/spec/graphql/dossier_spec.rb
index d4e3b14a9..7ff4cc1c3 100644
--- a/spec/graphql/dossier_spec.rb
+++ b/spec/graphql/dossier_spec.rb
@@ -26,6 +26,16 @@ RSpec.describe Types::DossierType, type: :graphql do
     end
   end
 
+  describe 'dossier with champs' do
+    let(:procedure) { create(:procedure, :published, :with_commune, :with_address) }
+    let(:dossier) { create(:dossier, :accepte, :with_populated_champs, procedure: procedure) }
+    let(:query) { DOSSIER_WITH_CHAMPS_QUERY }
+    let(:variables) { { number: dossier.id } }
+
+    it { expect(data[:dossier][:champs][0][:__typename]).to eq "CommuneChamp" }
+    it { expect(data[:dossier][:champs][1][:__typename]).to eq "AddressChamp" }
+  end
+
   DOSSIER_QUERY = <<-GRAPHQL
   query($number: Int!) {
     dossier(number: $number) {
@@ -48,4 +58,35 @@ RSpec.describe Types::DossierType, type: :graphql do
     }
   }
   GRAPHQL
+
+  DOSSIER_WITH_CHAMPS_QUERY = <<-GRAPHQL
+  query($number: Int!) {
+    dossier(number: $number) {
+      id
+      number
+      champs {
+        id
+        label
+        __typename
+        ...CommuneChampFragment
+        ... on AddressChamp {
+          address {
+            ...AddressFragment
+          }
+        }
+      }
+    }
+  }
+  fragment CommuneChampFragment on CommuneChamp {
+    commune {
+      ...CommuneFragment
+    }
+  }
+  fragment CommuneFragment on Commune {
+    code
+  }
+  fragment AddressFragment on Address {
+    cityName
+  }
+  GRAPHQL
 end