Courses
1. Introduction to Blockchain and Solana
2. Setting Up Your Development Environment
3. Solana Architecture and Key Concepts
4. Creating and Managing Wallets
5. Understanding Solana Programs
6. Building Your First Solana Program
7. Deploying Programs on the Solana Network
8. Interacting with Solana Programs
9. Using Solana CLI and SDKs
10. Developing Decentralized Applications (DApps)
11. Smart Contract Security Best Practices
12. Testing and Debugging Solana Programs
13. Optimizing Performance on Solana
14. Exploring Solana Ecosystem Tools
1. Introduction to Blockchain and Ethereum
2. Setting Up Your Development Environment
3. Ethereum Architecture and Key Concepts
4. Creating and Managing Wallets
5. Understanding Smart Contracts
6. Building Your First Smart Contract
7. Deploying Smart Contracts on the Ethereum Network
8. Interacting with Smart Contracts
9. Using Ethereum CLI and SDKs
10. Developing Decentralized Applications (DApps)
11. Smart Contract Security Best Practices
12. Testing and Debugging Smart Contracts
13. Optimizing Performance on Ethereum
14. Exploring Ethereum Ecosystem Tools
1. Introduction to Cybersecurity
2. Report Writing for Penetration Testers
3. Information Gathering
4. Vulnerability Scanning
5. Introduction to Web Applications
6. Common Web Application Attacks
7. SQL Injection Attacks
8. Client-Side Attacks
9. Locating Public Exploits
10. Fixing Exploits
11. Antivirus Evasion
12. Password Attacks
13. Windows Privilege Escalation
14. Linux Privilege Escalation
15. Advanced Tunneling
16. The Metasploit Framework
17. Active Directory: Introduction and Enumeration
18. Attacking Active Directory Authentication
19. Lateral Movement in Active Directory
1. JavaScript Prototype Pollution
2. Advanced Server-Side Request Forgery (SSRF)
3. Web Security Tools and Methodologies
4. Source Code Analysis
5. Persistent Cross-Site Scripting
6. Session Hijacking
7. .NET Deserialization
8. Remote Code Execution
9. Blind SQL Injection
10. Data Exfiltration
11. Bypassing File Upload Restrictions and File Extension Filters
12. PHP Type Juggling with Loose Comparisons
13. PostgreSQL Extension and User-Defined Functions
14. Bypassing REGEX Restrictions
15. Magic Hashes
16. Bypassing Character Restrictions
17. UDF Reverse Shells
18. PostgreSQL Large Objects
19. DOM-Based Cross-Site Scripting (Black Box)
20. Server-Side Template Injection
21. Weak Random Token Generation
22. XML External Entity Injection
23. RCE via Database Functions
24. OS Command Injection via WebSockets (Black Box)
Developing Decentralized Applications (DApps) on Polygon
Polygon · Chapter 10
Developing Decentralized Applications (DApps) on Polygon
A DApp connects a familiar website to a smart contract. For the Counter app, the screen only needs the current value, a Connect Wallet button and an Increment button.
The basics
- Read the value when the page loads. Show the selected network beside it.
- Before a write, require the wallet to be on Amoy. Do not silently send a transaction to a different chain.
- Show wallet rejection, pending confirmation and transaction failure as separate states. Disable repeated submissions while waiting.
Try it yourself
Draw the Counter screen in four states: disconnected, connected, waiting and confirmed. Write a short message for a user who rejects the transaction.