Build a real project · Beginner
Guided course: build a crowdfunding dApp
This is a guided course: instead of separate topics, you build one project — a Kickstarter-style crowdfunding dApp — from cargo near new to a verified mainnet deploy. Creators open campaigns with a goal and a deadline, backers pledge NEAR or a NEP-141 token, and when time is up the creator claims the funds or every backer pulls a refund.
Each lesson is a milestone. It states the goal, shows the code you add (full files where it matters, the exact delta otherwise), explains why it works on NEAR — with Solidity side by side where there is a real analog — and ends with a checklist of what should now work. Names, methods and storage prefixes stay the same from lesson to lesson, so the pieces add up to one contract, printed in full in the final lesson.
It assumes you know Rust basics and the NEAR fundamentals from NEAR by Example. Along the way you meet the things that trip up EVM developers in real projects: storage that someone must pay for, transfers that complete after your method returns, callbacks that must repair state, tokens that arrive by ft_on_transfer, and views that must stay bounded.
12 lessons~150 min36 quiz questionsFree · no sign-up
What you’ll learn
- Scaffold, build and test a NEAR contract with
cargo nearand near-workspaces - Model state with
near_sdk::storecollections and make callers pay for the storage they add - Accept NEAR with
#[payable]methods and enforce deadlines with block timestamps - Pay out safely: deduct first, transfer, and restore state in
#[private]callbacks - Receive NEP-141 tokens through
ft_on_transferand pay them out with 1 yoctoNEARft_transfer - Emit NEP-297 events and design paginated, JavaScript-safe views
- Deploy to testnet and mainnet with near-cli-rs, and connect a wallet-selector frontend
- Ship verifiable builds (NEP-330) and upgrade a live contract with a state migration
Lessons
2. The contract
- Campaign state & initModel crowdfunding campaigns in near-sdk 5: a Campaign struct, store collections with prefixes, #[init], and create_campaign charging its creator for storage.
- Pledging NEARAccept NEAR pledges with a #[payable] method: track per-backer totals with tuple-keyed LookupMaps and charge each new backer for the storage they add.
3. Money out
- Deadline & claimEnforce a campaign deadline with env::block_timestamp_ms() and let the creator claim the funds with a NEAR transfer Promise once the goal is reached.
- Refunds and failure-safe payoutsLet backers pull refunds from failed NEAR campaigns: deduct first, transfer, then restore the pledge in a #[private] callback if the transfer fails.
4. Tokens, events & views
- Pledging with fungible tokensAccept NEP-141 token pledges with ft_on_transfer: check the token, return unused amounts, and pay out tokens with 1 yoctoNEAR ft_transfer plus a callback.
- Events for indexers and frontendsEmit NEP-297 events from the crowdfunding contract with #[near(event_json)]: EVENT_JSON logs for campaign created, pledged, claimed and refunded.
- Views & paginationDesign frontend-friendly NEAR view methods: a computed campaign status, paginated campaign and backer lists, and U128 strings for large amounts in JSON.
5. Ship it
- Sandbox tests with near-workspacesTest the crowdfunding contract in a local NEAR sandbox with near-workspaces: deploy, pledge, fast_forward past the deadline, claim, refund and failure paths.
- Deploy to testnetDeploy the crowdfunding contract to NEAR testnet: create accounts with near-cli-rs, cargo near deploy with an init call, then pledge and query campaigns.
- A small web frontendBuild a NEAR dApp frontend in TypeScript: wallet-selector sign-in, free RPC view calls, and a payable pledge function call with an attached NEAR deposit.
- Going to mainnet & upgradesShip the crowdfunding dApp to NEAR mainnet: a pre-launch audit, reproducible builds with NEP-330 metadata, upgrades with state migration, and the full contract.