The main repository for libraries used to build applications on the Atsign Platform. Three categories: SDKs, libraries, and Flutter widgets.
- at_client: the platform-neutral Dart SDK, for command-line apps, headless services, and Internet-of-Things devices.
- at_client_flutter: the Flutter
layer on top of
at_client, for mobile and desktop apps. Adds onboarding / authentication dialogs and device-keychain storage. Flutter web is not a supported target.
Dart libraries for building Atsign Platform applications. All are published on pub.dev.
- at_auth: platform-neutral core of onboarding, authentication, and APKAM enrollment.
- at_chops: cryptographic and hashing operations (encryption, decryption, signing, hashing) used by the rest of the SDK.
- at_cli_commons: helpers for Dart CLI
/ server programs that use
at_client. Wraps the boilerplate of parsing flags, loading keys, and producing an authenticatedAtClient. - at_commons: foundational types used across every package: keys, metadata, atSign validation, root-domain parsing, verb builders for the Atsign Protocol wire format, and the exception hierarchy.
- at_contact: contacts library that persists across different Atsign Platform applications.
- at_lookup: low-level direct
implementation of the Atsign Protocol verbs. Used by
at_clientandat_client_mobile. - at_onboarding_cli: command-line tooling and library surface for registering, onboarding, and enrolling atSigns. Useful for headless / IoT applications.
- at_policy: scaffolding for building policy-management services that talk to enforcement endpoints via the Atsign Protocol.
- at_server_status: logs the status of the root server and the atServer for an atSign of your choice.
- at_utils: utility library: atSign, metadata, configuration, logger.
- base2e15: fork of the upstream base2e15 package, kept here for null-safety support.
- dart_utf7: fork of the upstream utf7 package, kept here for null-safety support.
Status: Most of the
at_*_flutterpackages listed below are in the process of being deprecated. Over the next few months they'll be replaced by example application code rather than reusable widget packages. The recommended path for new Flutter work is to read the example app atpackages/at_client_flutter/examples/todosand adapt it directly. The packages will continue to publish until that migration completes.
- at_backupkey_flutter: saves the backup key file for an onboarded atSign.
- at_chat_flutter: chat feature using atSigns and the Atsign Protocol.
- at_common_flutter: common
widgets used by other Atsign Flutter packages. Already
deprecated in favour of
at_client_flutter. - at_contacts_flutter: contact-management widgets for atSign-based apps.
- at_contacts_group_flutter:
group functionality on top of
at_contacts_flutter. - at_events_flutter: event management.
- at_follows_flutter: a basic social "follows" feature for atSigns.
- at_invitation_flutter:
deprecated; invite contacts via SMS or email using the
at_client_fluttersnippet. - at_location_flutter: share location between two atSigns and view on OpenStreetMap.
- at_login_flutter: zero-trust logins using the Atsign Protocol.
- at_notify_flutter: notification surface.
- at_sync_ui_flutter: UI indicator for the SDK's sync process.
- at_theme_flutter: theme switching.
Each package's own README and pub.dev page have the installation details. Click any of the links above.
The at_client_skills package gives AI agents accurate, up-to-date knowledge of
at_client and at_client_flutter — covering AtCollection<T>, auth flows,
querying, sub-collections, testing patterns, and common pitfalls.
# Add to your project
dart pub add --dev at_client_skills skills
# Install the skill into your IDE
dart run skills getWorks with Claude Code, Cursor, GitHub Copilot, Cline, and any agent supporting the agentskills.io specification.