diff --git a/21_skillsharing/package-lock.json b/21_skillsharing/package-lock.json
index c6d7a86..ee65158 100644
--- a/21_skillsharing/package-lock.json
+++ b/21_skillsharing/package-lock.json
@@ -4,36 +4,56 @@
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+                              "resolved": "https://registry.npmjs.org/ecstatic/-/ecstatic-4.1.4.tgz",
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                               "requires": {
+                                        "charset": "^1.0.1",
                                         "he": "^1.1.1",
-                                        "mime": "^1.6.0",
+                                        "mime": "^2.4.1",
                                         "minimist": "^1.1.0",
-                                        "url-join": "^2.0.5"
+                                        "on-finished": "^2.3.0",
+                                        "url-join": "^4.0.0"
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+                              "resolved": "https://registry.npmjs.org/ee-first/-/ee-first-1.1.1.tgz",
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+                              "resolved": "https://registry.npmjs.org/on-finished/-/on-finished-2.3.0.tgz",
+                              "integrity": "sha1-IPEzZIGwg811M3mSoWlxqi2QaUc=",
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-                              "resolved": "https://registry.npmjs.org/url-join/-/url-join-2.0.5.tgz",
-                              "integrity": "sha1-WvIvGMBSoACkjXuCxenC4v7tpyg="
+                              "version": "4.0.1",
+                              "resolved": "https://registry.npmjs.org/url-join/-/url-join-4.0.1.tgz",
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diff --git a/21_skillsharing/package.json b/21_skillsharing/package.json
index a3d9d62..9076871 100644
--- a/21_skillsharing/package.json
+++ b/21_skillsharing/package.json
@@ -4,7 +4,7 @@
           "main": "skillsharing_server.js",
           "description": "Skill-sharing website example from Eloquent JavaScript",
           "dependencies": {
-                    "ecstatic": "^3.1.0"
+                    "ecstatic": "^4.1.4"
           },
           "licenses": [
                     {