diff --git a/src/types/mod_json.rs b/src/types/mod_json.rs
index f54af57..a756e00 100644
--- a/src/types/mod_json.rs
+++ b/src/types/mod_json.rs
@@ -78,12 +78,30 @@ pub enum ModJsonDependencyType {
 }
 
 #[derive(Deserialize, Debug)]
-pub struct ModJsonDependency {
+pub struct ModJsonDependencyOnlyVersion {
+    version: String,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct ModJsonDependencyWithImportance {
     version: String,
-    #[serde(default)]
     importance: DependencyImportance,
 }
 
+#[derive(Deserialize, Debug)]
+pub struct ModJsonDependencyWithRequired {
+    version: String,
+    required: bool,
+}
+
+#[derive(Deserialize, Debug)]
+#[serde(untagged)]
+pub enum ModJsonDependency {
+    WithImportance(ModJsonDependencyWithImportance),
+    WithRequired(ModJsonDependencyWithRequired),
+    OnlyVersion(ModJsonDependencyOnlyVersion),
+}
+
 #[derive(Deserialize, Debug)]
 pub struct OldModJsonDependency {
     pub id: String,
@@ -107,10 +125,27 @@ pub enum ModJsonIncompatibilityType {
 }
 
 #[derive(Deserialize, Debug)]
-pub struct ModJsonIncompatibility {
+pub struct ModJsonIncompatibilityOnlyVersion {
     version: String,
-    #[serde(default)]
-    pub importance: IncompatibilityImportance,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct ModJsonIncompatibilityWithImportance {
+    version: String,
+    importance: IncompatibilityImportance,
+}
+
+#[derive(Deserialize, Debug)]
+pub struct ModJsonIncompatibilityWithBreaking {
+    version: String,
+    breaking: bool,
+}
+
+#[derive(Deserialize, Debug)]
+pub enum ModJsonIncompatibility {
+    WithImportance(ModJsonIncompatibilityWithImportance),
+    WithBreaking(ModJsonIncompatibilityWithBreaking),
+    OnlyVersion(ModJsonIncompatibilityOnlyVersion),
 }
 
 #[derive(Deserialize, Debug)]
@@ -250,18 +285,33 @@ impl ModJson {
                             });
                         }
                         ModJsonDependencyType::Detailed(detailed) => {
-                            let (dependency_ver, compare) =
-                                split_version_and_compare(&(detailed.version)).map_err(|_| {
+                            let (dep_ver, importance) = match detailed {
+                                ModJsonDependency::OnlyVersion(data) => {
+                                    (&data.version, DependencyImportance::default())
+                                }
+                                ModJsonDependency::WithRequired(data) => (
+                                    &data.version,
+                                    match data.required {
+                                        true => DependencyImportance::Required,
+                                        false => DependencyImportance::Recommended,
+                                    },
+                                ),
+                                ModJsonDependency::WithImportance(data) => {
+                                    (&data.version, data.importance)
+                                }
+                            };
+                            let (dependency_ver, compare) = split_version_and_compare(dep_ver)
+                                .map_err(|_| {
                                     ModZipError::InvalidModJson(format!(
                                         "Invalid semver {}",
-                                        detailed.version
+                                        dep_ver
                                     ))
                                 })?;
                             ret.push(DependencyCreate {
                                 dependency_id: id.clone(),
                                 version: dependency_ver.to_string(),
                                 compare,
-                                importance: detailed.importance,
+                                importance,
                             });
                         }
                     }
@@ -336,18 +386,33 @@ impl ModJson {
                             });
                         }
                         ModJsonIncompatibilityType::Detailed(detailed) => {
-                            let (ver, compare) = split_version_and_compare(&(detailed.version))
-                                .map_err(|_| {
+                            let (inc_ver, importance) = match detailed {
+                                ModJsonIncompatibility::OnlyVersion(data) => {
+                                    (&data.version, IncompatibilityImportance::default())
+                                }
+                                ModJsonIncompatibility::WithBreaking(data) => (
+                                    &data.version,
+                                    match data.breaking {
+                                        true => IncompatibilityImportance::Breaking,
+                                        false => IncompatibilityImportance::Conflicting,
+                                    },
+                                ),
+                                ModJsonIncompatibility::WithImportance(data) => {
+                                    (&data.version, data.importance)
+                                }
+                            };
+                            let (ver, compare) =
+                                split_version_and_compare(inc_ver).map_err(|_| {
                                     ModZipError::InvalidModJson(format!(
                                         "Invalid semver {}",
-                                        detailed.version
+                                        inc_ver
                                     ))
                                 })?;
                             ret.push(IncompatibilityCreate {
                                 incompatibility_id: id.clone(),
                                 version: ver.to_string(),
                                 compare,
-                                importance: detailed.importance,
+                                importance,
                             });
                         }
                     }
@@ -393,6 +458,28 @@ impl ModJson {
             ));
         }
 
+        let v5: bool = {
+            let geode = Version::parse(self.geode.trim_start_matches('v'))
+                .map_err(|_| ModZipError::InvalidModJson("Invalid geode version".into()))?;
+            geode.major >= 5
+        };
+
+        // Don't allow array syntax for geode >= v5
+        if let Some(ModJsonDependencies::Old(_)) = &self.dependencies
+            && v5
+        {
+            return Err(ModZipError::InvalidModJson(
+                "Invalid dependencies key: should be an object".into(),
+            ));
+        }
+        if let Some(ModJsonIncompatibilities::Old(_)) = &self.incompatibilities
+            && v5
+        {
+            return Err(ModZipError::InvalidModJson(
+                "Invalid incompatibilities key: should be an object".into(),
+            ));
+        }
+
         if let Some(l) = &self.links {
             if let Some(community) = &l.community {
                 if let Err(e) = Url::parse(community) {
diff --git a/src/types/models/dependency.rs b/src/types/models/dependency.rs
index e477106..4e12cd8 100644
--- a/src/types/models/dependency.rs
+++ b/src/types/models/dependency.rs
@@ -21,6 +21,7 @@ pub struct ResponseDependency {
     pub mod_id: String,
     pub version: String,
     pub importance: DependencyImportance,
+    pub required: bool,
 }
 
 #[derive(sqlx::FromRow, Clone, Debug)]
@@ -44,6 +45,7 @@ impl FetchedDependency {
                 }
             },
             importance: self.importance,
+            required: self.importance == DependencyImportance::Required
         }
     }
     pub fn to_response(&self) -> ResponseDependency {
@@ -57,6 +59,7 @@ impl FetchedDependency {
                 }
             },
             importance: self.importance,
+            required: self.importance == DependencyImportance::Required
         }
     }
 }
@@ -93,7 +96,7 @@ impl Display for ModVersionCompare {
     }
 }
 
-#[derive(sqlx::Type, Debug, Deserialize, Serialize, Clone, Copy, Default)]
+#[derive(sqlx::Type, Debug, Deserialize, Serialize, Clone, Copy, Default, PartialEq)]
 #[sqlx(type_name = "dependency_importance", rename_all = "lowercase")]
 #[serde(rename_all = "lowercase")]
 pub enum DependencyImportance {
diff --git a/src/types/models/incompatibility.rs b/src/types/models/incompatibility.rs
index f44ab5d..e9dec24 100644
--- a/src/types/models/incompatibility.rs
+++ b/src/types/models/incompatibility.rs
@@ -54,6 +54,7 @@ pub struct ResponseIncompatibility {
     pub mod_id: String,
     pub version: String,
     pub importance: IncompatibilityImportance,
+    pub breaking: bool,
 }
 
 impl FetchedIncompatibility {
@@ -68,6 +69,7 @@ impl FetchedIncompatibility {
                 }
             },
             importance: self.importance,
+            breaking: self.importance == IncompatibilityImportance::Breaking,
         }
     }
 
@@ -82,6 +84,7 @@ impl FetchedIncompatibility {
                 }
             },
             importance: self.importance,
+            breaking: self.importance == IncompatibilityImportance::Breaking,
         }
     }
 }