Finish basic functionality

example/pubspec.lock

@@ -1,14 +1,6 @@
 # Generated by pub
 # See https://dart.dev/tools/pub/glossary#lockfile
 packages:
-  archive:
-    dependency: transitive
-    description:
-      name: archive
-      sha256: "2fde1607386ab523f7a36bb3e7edb43bd58e6edaf2ffb29d8a6d578b297fdbbd"
-      url: "https://pub.dev"
-    source: hosted
-    version: "4.0.7"
   args:
     dependency: transitive
     description:
@@ -65,14 +57,6 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.19.1"
-  crypto:
-    dependency: transitive
-    description:
-      name: crypto
-      sha256: "1e445881f28f22d6140f181e07737b22f1e099a5e1ff94b0af2f9e4a463f4855"
-      url: "https://pub.dev"
-    source: hosted
-    version: "3.0.6"
   cupertino_icons:
     dependency: "direct main"
     description:
@@ -306,14 +290,6 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.8"
-  posix:
-    dependency: transitive
-    description:
-      name: posix
-      sha256: "6323a5b0fa688b6a010df4905a56b00181479e6d10534cecfecede2aa55add61"
-      url: "https://pub.dev"
-    source: hosted
-    version: "6.0.3"
   pub_semver:
     dependency: transitive
     description: