diff --git a/lessons/lesson-4/yarn.lock b/lessons/lesson-4/yarn.lock
index c87e288..6589175 100644
--- a/lessons/lesson-4/yarn.lock
+++ b/lessons/lesson-4/yarn.lock
@@ -1209,8 +1209,9 @@ babel-runtime@^6.11.6:
     regenerator-runtime "^0.11.0"
 
 balanced-match@^1.0.0:
-  version "1.0.0"
-  resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.0.tgz#89b4d199ab2bee49de164ea02b89ce462d71b767"
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.2.tgz#e83e3a7e3f300b34cb9d87f615fa0cbf357690ee"
+  integrity sha512-3oSeUO0TMV67hN1AmbXsK4yaqU7tjiHlbxRDZOpH0KW9+CeX4bRAaX0Anxt0tx2MrpRpWwQaPwIlISEJhYU5Pw==
 
 base64-js@^1.1.2, base64-js@^1.2.3, base64-js@^1.3.0:
   version "1.3.0"
@@ -1259,6 +1260,7 @@ bplist-parser@0.1.1:
 brace-expansion@^1.1.7:
   version "1.1.11"
   resolved "https://registry.yarnpkg.com/brace-expansion/-/brace-expansion-1.1.11.tgz#3c7fcbf529d87226f3d2f52b966ff5271eb441dd"
+  integrity sha512-iCuPHDFgrHX7H2vEI/5xpz07zSHB00TpugqhmYtVmMO6518mCuRMoOYFldEBl0g187ufozdaHgWKcYFb61qGiA==
   dependencies:
     balanced-match "^1.0.0"
     concat-map "0.0.1"
@@ -1518,7 +1520,7 @@ compressible@~2.0.13:
 
 compression@^1.7.1:
   version "1.7.2"
-  resolved "http://registry.npmjs.org/compression/-/compression-1.7.2.tgz#aaffbcd6aaf854b44ebb280353d5ad1651f59a69"
+  resolved "https://registry.npmjs.org/compression/-/compression-1.7.2.tgz#aaffbcd6aaf854b44ebb280353d5ad1651f59a69"
   dependencies:
     accepts "~1.3.4"
     bytes "3.0.0"
@@ -1531,6 +1533,7 @@ compression@^1.7.1:
 concat-map@0.0.1:
   version "0.0.1"
   resolved "https://registry.yarnpkg.com/concat-map/-/concat-map-0.0.1.tgz#d8a96bd77fd68df7793a73036a3ba0d5405d477b"
+  integrity sha512-/Srv4dswyQNBfohGpz9o6Yb3Gz3SrUDqBH5rTuhGR7ahtlbYKnVxw2bCFMRljaA7EXHaXZ8wsHdodFvbkhKmqg==
 
 concat-stream@^1.6.0:
   version "1.6.2"
@@ -3563,8 +3566,9 @@ min-document@^2.19.0:
     dom-walk "^0.1.0"
 
 minimatch@^3.0.4:
-  version "3.0.4"
-  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.0.4.tgz#5166e286457f03306064be5497e8dbb0c3d32083"
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-3.1.2.tgz#19cd194bfd3e428f049a70817c038d89ab4be35b"
+  integrity sha512-J7p63hRiAjw1NDEww1W7i37+ByIrOWO5XQQAzZ3VOcL0PNybwpfmV/N05zFAzwQ9USyEcX6t3UO+K5aqBQOIHw==
   dependencies:
     brace-expansion "^1.1.7"