Overview
Kingpin Apps is a software studio that gives programmers free building blocks for crypto wallets and blockchain apps. Developers who write in Swift, the programming language Apple created for its devices, can use its code libraries to add wallet, signing, and transaction features without building them from scratch1. The studio also ships two finished tools, a command-line program called scm and an app called Cardano TxWorkshop, for people who build, check, and sign transactions themselves1.
That blockchain work is built for Cardano. Kingpin Apps is the trading name of Adderley Group Ltd. and has been writing software since 2009. It began with custom work for business clients and now focuses on its own products2. Besides the Cardano code, the studio makes a Dokploy Client app for managing Dokploy servers, self-hosted or on Dokploy Cloud, from Apple devices including iPhone, iPad, Mac, and Apple Watch, and a cycle companion app for its sister company Women's Haven3.
Key Features
- A ready-made wallet engine for apps. The swift-cardano-wallet library handles sending ADA, staking, minting NFTs, and voting in Cardano governance, so app developers can offer those actions without writing the underlying logic themselves4.
- Hardware wallet signing on iPhone and Mac. A separate library connects Ledger, Trezor One, and Keystone devices, so the app only ever holds public keys, which can work out wallet addresses but cannot sign transactions, while the physical device approves each transaction5.
- Pick only the parts you need. The Swift toolkit is split into five layers, from basic cryptography and data formats up to the wallet itself, and the studio publishes each package as an open-source library1.
- Freedom to switch data sources. Apps built on the wallet library read the blockchain through one setting that supports Blockfrost, Koios, Ogmios, Kupo, or an offline mode, so moving to a self-run Cardano node means changing a setting rather than rewriting code1.
- Transaction checks before signing. Cardano TxWorkshop opens a transaction file, shows what is inside, checks it against the network's rules, and then lets the user sign and submit it, with signing keys kept on the device6.
What to Expect
Everyday crypto users will not find a consumer wallet to download here. Kingpin Apps aims its Cardano work at people who build or operate things, and it says its own apps are built on the same libraries it publishes2.
Swift developers will find each library on the studio's GitHub page, with setup steps in the project's readme file. Generated reference pages for the packages are also published on the Swift Package Index, a public catalog of Swift code libraries7.
Stake pool operators and power users who prefer a terminal can install scm through the Homebrew package manager, a Debian or Ubuntu package, or a ready-made Docker container image. From one menu-driven program, they can run node software, manage keys, build and submit transactions, and query the chain. The tool also supports air-gapped setups, where signing happens on a computer that never connects to the internet8.
Mac users who want a visual tool can download Cardano TxWorkshop. The app saves each transaction as a document that holds notes, the signatures collected for it, and the chain data needed to re-check it offline6. The studio's contact page takes questions about its apps, bug reports, partnership ideas, and press requests9, and the site also lists an email address and a support desk2.
