Blockchain & Smart Contracts Internship
Build blockchain apps on test networks: Solidity contracts in Remix, Hardhat or Foundry, testing, ERC-20 and ERC-721 tokens, wallet-connected frontends with ethers.js, safety patterns, static analysis and permissioned chains.
What you'll work on
- Level 1: Foundations - Blockchain basics, Hashing in code, Wallet on a test network and more
- Level 2: Building real features - Hardhat or Foundry project, Unit tests, ERC-20 token and more
- Level 3: Professional work and capstone - Static analysis, Gas optimisation, Certificate verification system and more
Full syllabus: all 30 graded tasks
These are the actual tasks the internship portal assigns for this domain. You submit each one with proof (a GitHub link or document) and a mentor reviews it.
Level 1: Foundations (12 tasks)
- Blockchain basics. In a repo named web3-internship, explain blocks, hashes, consensus, wallets, gas and public versus private chains with simple diagrams.
- Hashing in code. Write a small Python or JavaScript program that chains blocks with SHA-256 hashes and shows how changing one block breaks the chain.
- Wallet on a test network. Set up a browser wallet on a test network (for example Sepolia), get free test coins from a faucet and send a test transaction. Never use real money.
- Block explorer. Look up your test transaction on a block explorer and explain every field.
- Remix IDE. Write, compile and deploy a Hello World contract in Remix on the test network.
- Solidity types and functions. Write a contract with state variables, functions, view and pure functions, and events.
- Mappings and structs. Build a contract that stores student records with structs and mappings.
- Modifiers and access control. Add an onlyOwner modifier and explain why access control matters in contracts.
- Errors and require. Use require, revert and custom errors, and test what happens on bad input.
- Gas costs. Compare the gas used by two ways of writing the same function and explain why one is cheaper.
- Token standards. Explain the ERC-20 and ERC-721 standards and where they are used.
- Legal and safety notes. Write a page on crypto rules in India, scams to avoid and why internship work uses only test networks.
Level 2: Building real features (10 tasks)
- Hardhat or Foundry project. Set up a Hardhat or Foundry project, compile a contract and deploy it with a script to a local chain and a test network.
- Unit tests. Write tests for your contracts covering normal use, edge cases and failures.
- ERC-20 token. Create a test-network ERC-20 token with OpenZeppelin, mint some and transfer it between test wallets.
- NFT certificate. Create an ERC-721 contract that issues a test certificate NFT with metadata stored on IPFS.
- Frontend connection. Build a web page with ethers.js or viem that connects a wallet, reads contract data and sends a transaction.
- Events and indexing. Emit events from your contract and show them live in your frontend.
- Voting dApp. Build a voting contract and frontend where each test wallet votes once and results update live.
- Common bugs. Study reentrancy, integer issues and unchecked calls using public write-ups, and show how OpenZeppelin patterns prevent them in your own code.
- Upgradeable contracts. Explain proxy patterns and deploy an upgradeable contract with OpenZeppelin on a test network.
- Verify a contract. Verify your contract's source code on the test network's block explorer.
Level 3: Professional work and capstone (8 tasks)
- Static analysis. Run Slither or a similar tool on your contracts, explain each finding and fix the real issues.
- Gas optimisation. Reduce the gas cost of your main contract and show before and after numbers.
- Certificate verification system. Build a dApp where an institution issues certificates on a test chain and anyone can verify them by ID.
- Layer 2. Deploy your contract to a Layer 2 test network and compare fees and speed with the main test network.
- Private blockchain. Set up a small permissioned network (Hyperledger Besu or Fabric test network) and explain where businesses use permissioned chains.
- Audit report. Write an audit-style report for your own capstone contract: scope, findings, severity and fixes.
- Documentation. Write developer documentation for your dApp: contracts, functions, deployment and how to run tests.
- Capstone: dApp. Ship a complete test-network dApp (certificates, supply-chain tracking or voting) with tested contracts, a frontend and a hosted link. Submit the repo and a 2-minute demo video.
Real software work, not just training
Every Blockchain & Smart Contracts task is reviewed by our team and saved to your portfolio. Interns who pass the readiness check can take real work from Training Trains, W3AppDevelopers and DomainHostly projects on the Company Work board.
Frequently asked questions
Do I need experience to join the Blockchain & Smart Contracts internship?+
Basic JavaScript helps. Everything uses free test networks and test coins; no real money is ever used.
What will I do in the Blockchain & Smart Contracts internship?+
You complete 30 graded tasks in three levels: foundations, real features, and professional work. Each task is submitted with GitHub or document proof and reviewed. The final capstone is: Capstone: dApp.
Do I get a certificate for the Blockchain & Smart Contracts internship?+
Yes. After your required tasks are approved, your attendance is above 75% and you pass the proctored final exam, you get a graded completion certificate that anyone can verify at trainingtrains.com/verify.
Can I do the Blockchain & Smart Contracts internship online?+
Yes. You can do it fully online from home, or offline at our Erode and Perundurai branches. Tasks, quizzes and mentor reviews are the same in both modes.
Available both online (work from home) and offline at our Erode and Perundurai branches - see the full internship program details for departments, duration, and the application process.