Building a Crypto‑Native Fantasy Sports dApp on Cardano

Daedalus: Full‑node wallet for development and testing

Purpose: A secure, full‑node wallet that downloads the entire Cardano blockchain for offline verification. Ideal for dev/test of token minting, transactions, and dApp interactions.

• Download and install: From daedaluswallet.io; the chain auto‑downloads (~200GB as of 2025).
• Create or restore wallet: Generate and securely back up the 24‑word recovery phrase; set a password.
• Fund wallet: Use a testnet faucet for tADA; for mainnet, acquire ADA on an exchange and transfer.
• Send/receive ADA: Use "Send" and "Receive" tabs to test payments and integrations.
• Delegate/stake: Delegate to a pool to test staking models and rewards flows.
• Integrate with dApp: Use cardano‑wallet API to simulate user connections during QA.

Identus: Decentralized identity for user verification

Purpose: Self‑sovereign identity with verifiable credentials (VCs) to verify user age/location for compliance without storing personal data on‑chain.

• Set up environment: Clone the Hyperledger Identus repo; install Node.js 18+ and Docker; run npm install in agent‑sdk‑ts.
• Create a DID: Generate keys and derive a DID via the Identus Agent SDK.
• Issue credentials: Define schemas (e.g., AgeOver18) and issue VCs to user DIDs.
• Integrate in app: Request/verify VCs via QR or SDK; verify proofs programmatically.
• Test on Cardano: Use testnet and Cardano DID support; leverage quick‑start workshop code.

Lace: Light wallet for user‑friendly dApp access

Purpose: Browser‑based wallet with dApp integration for seamless crypto entries and payments in ADA or $BEEP.

• Install Lace: Use Chrome/Firefox extension or mobile app; create/import wallet.
• Fund and manage assets: Add ADA; mint and view multi‑assets including $BEEP.
• Connect to dApp: Enable Lace via window.cardano.lace and prompt user connection.
• Sign transactions: Build tx off‑chain (e.g., Mesh.js) and request signature.
• Use features: Stake ADA, access DeFi, and swap into $BEEP as needed.
• Mobile integration: Bridge connections via WebView and mobile SDK.

Catalyst: Community funding for app development

Purpose: Decentralized grants via community voting to fund token launch, smart contracts, and growth.

• Prepare proposal: Clear title, concise summary, quantified impact, transparent budget, and milestones.
• Submit via app: Connect wallet, complete forms, and include a video pitch.
• Community review: Gather feedback on Cardano forums and respond proactively.
• Voting phase: Track shortlist status and voting results in app dashboards.
• If funded: Report progress quarterly and allocate for hires/tools; target upcoming funds.

Marlowe: User‑friendly smart contracts for game logic

Purpose: DSL for financial contracts with visual tools to model contest entries, timeouts, and payouts.

• Access Playground: Use the web UI to design contracts with drag‑and‑drop blocks.
• Write contract: Define deposits, timeouts, and payout conditions tied to oracle data.
• Simulate: Run scenarios to validate timelines and payout behavior.
• Compile to Cardano: Export text and build via Marlowe CLI on testnet.
• Deploy: Submit transactions and test on previewnet.
• Integrate: Query state via Marlowe Runtime for live entry tracking.

Plutus (Plinth): Advanced smart contracts for complex logic

Purpose: Cardano's native smart contract platform (with Plinth for safer subsets) to support complex features like on‑chain scoring or randomness.

• Set up dev environment: Install Nix, enter Plutus shells, and follow official docs.
• Write on‑chain code: Implement validators in Haskell/Plinth and compile to Plutus Core.
• Off‑chain client: Use plutus‑apps to build and sign transactions.
• Test: Run emulator scenarios for entries and payouts.
• Deploy: Build Alonzo‑era scripts and submit via CLI/wallet.
• Verify: Apply property tests and formal methods to reduce defects.

Midnight: Privacy‑focused sidechain for sensitive data

Purpose: Cardano sidechain using zero‑knowledge proofs to keep entries and personal data private while meeting regulatory requirements.

• Access network: Join devnet and install tooling for ZK development.
• Set up wallet: Manage NIGHT tokens and configure sidechain accounts.
• Build private dApp: Write ZK circuits (e.g., private entry proofs) and generate attestations.
• Integrate with Cardano: Bridge assets and verify proofs via SDK.
• Test: Simulate shielded transactions on devnet.
• Deploy: Submit private transactions and confirm via explorers.

Nami: Browser wallet for quick dApp connections

Purpose: Lightweight extension that enables users to connect and pay quickly; a fallback if Lace isn't available.

• Install: Add extension; create or import wallet.
• Connect to dApp: Detect window.cardano.nami and prompt enable.
• Sign payments: Build unsigned tx and request signature.
• Manage tokens: Add $BEEP policy ID post‑mint and verify in assets.
• Mobile: Use WebView to simulate extension flows.

RealFi: DeFi platform for lending and borrowing

Purpose: Access lending markets and real‑world asset rails so users can borrow ADA/$BEEP against collateral to enter contests.

• Access platform: Connect wallet and discover available pools.
• Deposit collateral: Provide ADA liquidity to earn yields.
• Borrow: Request loans against NFT/ADA collateral with wallet approval.
• Integrate in app: Use APIs to query rates and build borrow tx off‑chain.
• Repay: Hook contest winnings to auto‑repay loan via contract.
• Test: Use testnet pools and monitor behaviors.

Launching your coin ($BEEP) to support development

Purpose: Mint a native token for app funding and fees (e.g., 1% to treasury) to incentivize ecosystem growth.

• Prepare metadata: Create JSON (name, ticker, description) and register with CIP metadata resources.
• Generate policy: Build a single‑mint policy and derive the policy ID.
• Build mint transaction: Construct Alonzo‑era tx including mint amount and metadata.
• Sign and submit: Sign with payment key and submit on testnet/mainnet.
• List on DEX: Provide liquidity on Minswap and establish an ADA/$BEEP pair.
• Integrate: Enable entry payments in $BEEP; route 1% fee to treasury wallet.

Final tips, security, and timeline

• Mobile integration: Use Cardano mobile SDKs with deep links/QR bridges for wallet connections.
• Security: Audit contracts with reputable firms; start on testnet and enforce key management best practices.
• Timeline (suggested):
  Week 1: Wallets and Cardano setup. Weeks 2–4: Token + smart contracts. Month 2: Catalyst submission and launch.
• Community: Join Cardano and developer channels for faster feedback loops.