diff --git a/book/4-end/server/logs.js b/book/4-end/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/4-end/server/logs.js
+++ b/book/4-end/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/5-end/server/logs.js b/book/5-end/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/5-end/server/logs.js
+++ b/book/5-end/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/5-start/server/logs.js b/book/5-start/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/5-start/server/logs.js
+++ b/book/5-start/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/6-end/server/logs.js b/book/6-end/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/6-end/server/logs.js
+++ b/book/6-end/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/6-start/server/logs.js b/book/6-start/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/6-start/server/logs.js
+++ b/book/6-start/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/7-end/server/logs.js b/book/7-end/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/7-end/server/logs.js
+++ b/book/7-end/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/7-start/server/logs.js b/book/7-start/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/7-start/server/logs.js
+++ b/book/7-start/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/8-end/server/logs.js b/book/8-end/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/8-end/server/logs.js
+++ b/book/8-end/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/book/8-start/server/logs.js b/book/8-start/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/book/8-start/server/logs.js
+++ b/book/8-start/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });
 
diff --git a/server/logs.js b/server/logs.js
index 7a4c5a65b..1e0d5fffd 100644
--- a/server/logs.js
+++ b/server/logs.js
@@ -2,7 +2,7 @@ const winston = require('winston');
 
 const logger = winston.createLogger({
   level: process.env.NODE_ENV === 'production' ? 'info' : 'debug',
-  format: winston.format.simple(),
+  format: winston.format.combine(winston.format.splat(), winston.format.simple()),
   transports: [new winston.transports.Console()],
 });