diff --git a/src/ExampleOutput/Middleware.ts b/src/ExampleOutput/Middleware.ts
index 006a148..c5c2a5b 100644
--- a/src/ExampleOutput/Middleware.ts
+++ b/src/ExampleOutput/Middleware.ts
@@ -32,6 +32,30 @@
         res.send(toPayload(node));
     });
 
+    route.post("/nodes/:id(\\d+)", (req, res) => {
+        const id = Number.parseInt(req.params.id, undefined);
+        const existingItem = findSingle(graph, id);
+        const parsed = parseGraphNodeInput(req.body);
+        if(!parsed.isSuccessful) {
+            res.status(400).send(parsed.errorMessage);
+            return;
+        }
+        const inputItem = parsed.value;
+        if(existingItem == null) {
+            res.status(404).send("Not found");
+            return;
+        }
+        else {
+            // update
+            existingItem.name = inputItem.name;
+            existingItem.description = inputItem.description;
+            DataAccess.save(fileName, graph);
+            const payload = toPayload(existingItem);
+            res.status(200).send(payload);
+            return;
+        }
+    });
+
     route.get("/nodes", (req, res) => {
         const nodes = graph.nodes;
         res.send(nodes.map(toPayload));

diff --git a/src/ExampleOutput/Middleware.ts b/src/ExampleOutput/Middleware.ts
index 006a148..c5c2a5b 100644
--- a/src/ExampleOutput/Middleware.ts
+++ b/src/ExampleOutput/Middleware.ts
@@ -32,6 +32,30 @@
         res.send(toPayload(node));
     });
 
+    route.post("/nodes/:id(\\d+)", (req, res) => {
+        const id = Number.parseInt(req.params.id, undefined);
+        const existingItem = findSingle(graph, id);
+        const parsed = parseGraphNodeInput(req.body);
+        if(!parsed.isSuccessful) {
+            res.status(400).send(parsed.errorMessage);
+            return;
+        }
+        const inputItem = parsed.value;
+        if(existingItem == null) {
+            res.status(404).send("Not found");
+            return;
+        }
+        else {
+            // update
+            existingItem.name = inputItem.name;
+            existingItem.description = inputItem.description;
+            DataAccess.save(fileName, graph);
+            const payload = toPayload(existingItem);
+            res.status(200).send(payload);
+            return;
+        }
+    });
+
     route.get("/nodes", (req, res) => {
         const nodes = graph.nodes;
         res.send(nodes.map(toPayload));
diff --git a/src/MiddlewareGenerator.ts b/src/MiddlewareGenerator.ts
index 96e0704..903d8c1 100644
--- a/src/MiddlewareGenerator.ts
+++ b/src/MiddlewareGenerator.ts
@@ -51,6 +51,29 @@
         res.send(toPayload(item));
     });
 
+    route.post("${route}/:${entityId}(\\\\d+)", (req, res) => {
+        const id = Number.parseInt(req.params.${entityId}, undefined);
+        const existingItem = findSingle(${col}, id);
+        const parsed = parse${collection.entities.name}Input(req.body);
+        if(!parsed.isSuccessful) {
+            res.status(400).send(parsed.errorMessage);
+            return;
+        }
+        const inputItem = parsed.value;
+        if(existingItem == null) {
+            res.status(404).send("Not found");
+            return;
+        }
+        else {
+            // update
+            ${collection.entities.properties.map(p => `existingItem.${p.key} = inputItem.${p.key};`).join("\n\t\t\t")}
+            DataAccess.save(fileName, ${col});
+            const payload = toPayload(existingItem);
+            res.status(200).send(payload);
+            return;
+        }
+    });
+
     route.get("${route}", (req, res) => {
         const items = ${col}.items;
         res.send(items.map(toPayload));

diff --git a/src/ExampleOutput/Middleware.ts b/src/ExampleOutput/Middleware.ts
index 006a148..c5c2a5b 100644
--- a/src/ExampleOutput/Middleware.ts
+++ b/src/ExampleOutput/Middleware.ts
@@ -32,6 +32,30 @@
         res.send(toPayload(node));
     });
 
+    route.post("/nodes/:id(\\d+)", (req, res) => {
+        const id = Number.parseInt(req.params.id, undefined);
+        const existingItem = findSingle(graph, id);
+        const parsed = parseGraphNodeInput(req.body);
+        if(!parsed.isSuccessful) {
+            res.status(400).send(parsed.errorMessage);
+            return;
+        }
+        const inputItem = parsed.value;
+        if(existingItem == null) {
+            res.status(404).send("Not found");
+            return;
+        }
+        else {
+            // update
+            existingItem.name = inputItem.name;
+            existingItem.description = inputItem.description;
+            DataAccess.save(fileName, graph);
+            const payload = toPayload(existingItem);
+            res.status(200).send(payload);
+            return;
+        }
+    });
+
     route.get("/nodes", (req, res) => {
         const nodes = graph.nodes;
         res.send(nodes.map(toPayload));
diff --git a/src/MiddlewareGenerator.ts b/src/MiddlewareGenerator.ts
index 96e0704..903d8c1 100644
--- a/src/MiddlewareGenerator.ts
+++ b/src/MiddlewareGenerator.ts
@@ -51,6 +51,29 @@
         res.send(toPayload(item));
     });
 
+    route.post("${route}/:${entityId}(\\\\d+)", (req, res) => {
+        const id = Number.parseInt(req.params.${entityId}, undefined);
+        const existingItem = findSingle(${col}, id);
+        const parsed = parse${collection.entities.name}Input(req.body);
+        if(!parsed.isSuccessful) {
+            res.status(400).send(parsed.errorMessage);
+            return;
+        }
+        const inputItem = parsed.value;
+        if(existingItem == null) {
+            res.status(404).send("Not found");
+            return;
+        }
+        else {
+            // update
+            ${collection.entities.properties.map(p => `existingItem.${p.key} = inputItem.${p.key};`).join("\n\t\t\t")}
+            DataAccess.save(fileName, ${col});
+            const payload = toPayload(existingItem);
+            res.status(200).send(payload);
+            return;
+        }
+    });
+
     route.get("${route}", (req, res) => {
         const items = ${col}.items;
         res.send(items.map(toPayload));
diff --git a/src/OpenApiGenerator.ts b/src/OpenApiGenerator.ts
index c060754..b747ebe 100644
--- a/src/OpenApiGenerator.ts
+++ b/src/OpenApiGenerator.ts
@@ -137,6 +137,7 @@
     const route = itemRoute(collection);
     const path: OpenAPIV3.PathItemObject = {
         get: generateGetSpecificOperation(collection),
+        post: generatePostSpecificOperation(collection),
     };
     return [route, path];
 }
@@ -153,16 +154,7 @@
     const entity: Entity = collection.entities;
     const operation: OpenAPIV3.OperationObject = {
         tags: [collection.name],
-        parameters: [
-            {
-                in: "path",
-                name: idParameterName(entity),
-                required: true,
-                schema: {
-                    type: "integer",
-                },
-            },
-        ],
+        parameters: [entityPathParameter(entity)],
         responses: {
             "200": {
                 description: "Returns one specific " + entity.name,
@@ -182,6 +174,55 @@
     return operation;
 }
 
+function generatePostSpecificOperation(collection: Collection): OpenAPIV3.OperationObject {
+    const entity: Entity = collection.entities;
+    const operation: OpenAPIV3.OperationObject = {
+        tags: [collection.name],
+        parameters: [entityPathParameter(entity)],
+        requestBody: {
+            required: true,
+            description: "Data to replace a specific " + collection.entities.name,
+            content: {
+                "application/json": {
+                    schema: {
+                        $ref: "#/components/schemas/" + collection.entities.name + "Input"
+                    }
+                }
+            }
+        },
+        responses: {
+            "200": {
+                description: `Successfully updated the ${entity.name}`,
+                content: {
+                    "application/json": {
+                        schema: {
+                            $ref: "#/components/schemas/" + entity.name,
+                        }
+                    }
+                }
+            },
+            "400": {
+                $ref: "#/components/responses/BadRequest",
+            },
+            "404": {
+                $ref: "#/components/responses/NotFound",
+            }
+        }
+    };
+    return operation;
+}
+
+function entityPathParameter(entity: Entity): OpenAPIV3.ParameterObject {
+    return {
+        in: "path",
+        name: idParameterName(entity),
+        required: true,
+        schema: {
+            type: "integer",
+        },
+    };
+}
+
 const NotFoundResponse: OpenAPIV3.ResponseObject = {
     description: "The specified resource does not exist.",
     content: {