DFINITY Developer Release Notes

The DFINITY Canister Software Development Kit (SDK) enables developers to develop applications for the Internet Computer using the Motoko programing language. Motoko is a new programming language optimized for creating tamper-proof software and open internet services that will be hosted on the Internet Computer.

The DFINITY Canister SDK provides everything you need to perform the following key tasks:

  • Author canisters in Motoko and compile them to WebAssembly.

  • Run Internet Computer client processes locally on your development computer.

  • Deploy compiled programs as standalone canisters and interact with the canisters using a command-line interface.

This 0.5.4 version of the DFINITY Canister Software Development Kit (SDK) is an interim update of the Alpha release recently shared with the development community and made available to the public for preliminary testing, demonstration, and exploration. As part of our commitment to continuous improvement and iterative development focused on addressing developer feedback, this version includes numerous fixes and enhancements.

Note that DFINITY Canister Software Development Kit (SDK) and Motoko programming language are Alpha-quality releases intended to give you an early look at the potential for building applications that run on the Internet Computer. This 0.5.4 version of the software and programming language should not be used for developing production applications at this time.

Highlights of what’s new in 0.5.4

The 0.5.4 release includes the following new features and capabilities:

  • The Candid web interface now has a "Lucky" button that can generate random values when the input field is empty.

  • Various updates to JS userlib, including:

    • Unit is renamed to Null

    • Support Principal type

    • Support service and function references

  • Motoko now:

    • supports type argument inference for automatic instantiation of type-parametric functions;

    • adds primitive Principal and supporting (binary) Blob types

    • documents its support for caller identification (using principals) by selective parameterization of shared functions.

    • includes actor references and shared function types as shareable types that can be transmitted across canisters

  • Native support for Principal type in Candid (IDL).

  • Improvements to language server support.

  • Subcommand --clean of dfx start can be used to clean the state of current project.

    This clears checkpoints in your project and is helpful for starting your project from scratch or debugging.

  • Flags --v, --verbose and --q, --quiet for dfx can be used to toggle across various levels of information provided by messages, as desired.

    These flags affect messages only and not the output or return code of the process. Using the verbose flag twice, for example, will provide DEBUG and TRACE messages, the highest level of verbosity.

Issues fixed in this release

This section covers the issues fixed in this release. The 0.5.4 release includes the following fixes to reported issues:

  • Bug fix in stdlib and runtime system.

  • Bug fix for bootstrap load JS of non-latin encoding.

Known issues and limitations

This section covers any known issues or limitations that might affect how you work with the DFINITY Canister SDK in specific environments or scenarios. If there are workarounds to any of the issues described in this section, you can find them in the Troubleshooting section.

The 0.5.4 release includes the following known issues and limitations:

  • There is a breaking change to Motoko which removes definitions like debugPrint, abs and range from the default scope. You now have to import them through the Motoko standard library.

    For help with importing from the standard library, check out this section of the Motoko language reference and also the phonebook tutorial.

  • Float support in the Motoko programming language that is compiled to WebAssembly.

    Although Motoko recognizes floating point numbers, there are some limitations related to the deterministic requirements of the Internet Computer that can create issues when compiling Motoko source code that includes floating point data types into WebAssembly for deployment. To simplify the development of test and demonstration programs that run on the current 0.5.4 release, you should avoid using Float data types for now.

  • Using fixed-length Word data type arguments when running dfx commands.

    Fixed-length Word32 data types are not yet supported in the dfx command-line interface. As an alternative, you can convert integers to Word32 using the standard library function int32ToWord32(intToInt32(value))` until the support for fixed-length Word32 and Nat32 data types is added.

Additional questions and feedback

Check out Troubleshooting for additional technical support.