How to Make a Smart Contract Scanner Like De.Fi Scanner

As DeFi platforms continue to boom, securing smart contracts has become non-negotiable. We’ve all seen the headlines about hacks, vulnerabilities, and exploits, and it’s clear that without proper security measures, the risks only grow. In 2025, protecting these contracts isn’t just a good practice; it’s a must if you want to build trust with users and maintain a solid platform. 

By addressing security from the start, you’re not only preventing potential breaches but also protecting your users and your reputation from costly setbacks. It’s one of those “better safe than sorry” situations that can save you a lot of headaches down the road.

We’ve helped numerous DeFi platform founders build advanced smart contract scanners that proactively detect vulnerabilities such as reentrancy attacks, gas limit issues, and incorrect access controls. IdeaUsher has successfully implemented these solutions using AI and machine learning to enhance real-time detection, ensuring that contracts are secure before deployment. This approach provides scalability and reduces operational risk, helping protect your platform’s integrity while enhancing user trust. That’s why we’re sharing our knowledge through this blog, so you can learn how to make your platform more secure and efficient with smart contract scanning.

Key Market Takeaways for Smart Contract Scanners

According to GrandViewResearch, the smart contract market is rapidly expanding, with a valuation of $684.3 million in 2022 and an expected surge to $73.8 billion by 2030. This growth is driven by the increasing adoption of blockchain across sectors like finance, healthcare, and supply chain, where automation and secure, trustless transactions are becoming essential. As smart contracts play a central role in decentralized applications and digital assets, ensuring their security has become a major priority.

Source: GrandViewResearch

As more smart contracts are deployed, the risk of vulnerabilities, scams, and hacks continues to rise. This has led to an increased demand for smart contract scanners, tools that help detect issues before contracts go live. These scanners are crucial for identifying threats like honeypots and rug pulls and ensuring that contracts comply with best security practices, protecting both developers and investors.

Leading solutions like De.Fi Scanner provides in-depth vulnerability checks across various blockchains, including Ethereum and Solana. GoPlus offers broad-chain support with APIs and SDKs for transaction security, while SolidityScan uses AI to analyze over 160 vulnerability patterns. A standout partnership is between SolidityScan and Blockscout, which enables users to view real-time security scores and audit reports, making contract validation smoother and more accessible.

What is De.Fi Scanner and How Does It Work?

De.Fi Scanner is a comprehensive security solution designed to protect users in the world of Web3 and cryptocurrency by providing deep analysis of smart contracts, tokenomics, and blockchain transactions. Unlike traditional smart contract analyzers, which focus only on code vulnerabilities, De.Fi goes a step further with its holistic approach, offering protection across multiple facets of the blockchain ecosystem. This makes De.Fi Scanner a unique, all-in-one tool for traders, developers, and enterprises.

De.Fi’s Unique Positioning in Web3 Security

De.Fi stands out in the Web3 security space by not only detecting code flaws but also safeguarding against a variety of real-world risks:

• Wallet Risk Scanning – Identifying malicious token approvals that could compromise user wallets.
• Governance & Admin Control Analysis – Examining who can modify a contract and ensuring malicious actors cannot exploit admin privileges.
• Tokenomics & Liquidity Checks – Evaluating token distribution and liquidity pools to detect potential rug pulls and other manipulative actions.
• Investor Protection Tools – Offering real-time alerts, a REKT exploit database, and other features that help users avoid potential scams and fraud.

With this multi-layered approach, De.Fi Scanner aims to protect against the risks that come with the dynamic nature of the crypto world.

How Does De.Fi Scanner Work?

De.Fi Scanner works by analyzing a smart contract’s code and behavior, checking for vulnerabilities like reentrancy attacks or rug pulls. It then generates a risk report, giving you actionable insights to secure your assets before problems arise.

1. Input: User Submits a Smart Contract Address

To begin, users provide the contract address of the token, NFT, or DeFi protocol they wish to scan. De.Fi supports multiple blockchains, including Ethereum, BNB Chain, Polygon, and others, allowing users to analyze contracts across a wide range of platforms.

2. Blockchain Interaction: Fetching Live Data

Once the contract address is submitted, De.Fi connects to blockchain nodes using providers like Infura or QuickNode to retrieve live data. This includes the latest bytecode and transaction history, which form the foundation for the analysis.

3. Data Retrieval: Source Code & Bytecode Analysis

De.Fi first attempts to retrieve the verified source code from blockchain explorers like Etherscan or BscScan. However, many contracts are either unverified or obfuscated. In these cases, De.Fi uses advanced decompilers and heuristic analysis to infer the contract’s functionality, ensuring comprehensive coverage even for complex contracts.

4. Static Code Analysis: Detecting Common Vulnerabilities

The scanner performs a detailed inspection of the code to identify high-risk patterns such as:

• Reentrancy Attacks: Exploits due to unsafe external calls.
• Access Control Flaws: Potential vulnerabilities in admin functions.
• Integer Overflows/Underflows: Exploitable math errors in smart contracts.
• Honeypot Indicators: Detecting if users can trade or are stuck due to restrictions.
• Rug Pull Logic: Identifying hidden functions that could be used for liquidity removal or minting new tokens maliciously.

5. Dynamic & Behavioral Analysis: Simulating Real-World Risks

In addition to static code analysis, De.Fi also conducts dynamic and behavioral analysis to understand how the contract behaves under real-world conditions. This includes:

6. Vulnerability & Heuristic Engines

De.Fi also maintains an internal exploit database, which is continuously updated with new attack vectors, such as flash loan exploits and oracle manipulations. Additionally, it employs custom detection logic for emerging token standards (e.g., ERC-20, ERC-721, ERC-4626) and DeFi primitives (e.g., perpetuals, yield vaults), keeping up with the latest trends in the Web3 space.

7. Risk Scoring & Reporting: Clear, Actionable Insights

After the analysis is complete, De.Fi generates a risk report that is easy to understand and actionable. The report includes:

• De.Fi Score: A score ranging from 1 to 100 that indicates the overall risk level of the contract.
• Threat Levels: Categorized into Critical, High, Medium, Low, or Informational, providing an at-a-glance understanding of the severity of each risk.
• Remediation Suggestions: Clear recommendations on how to fix identified vulnerabilities, whether through code changes or governance adjustments.
• Liquidity & Tokenomics Warnings: Highlighting potential risks, such as the likelihood of a rug pull or token manipulation.

Why Does This Matter for Businesses and Enterprises?

For businesses, De.Fi Scanner is crucial for securing platforms, reducing risks, and building trust with users. It helps streamline compliance and development while setting you apart as a security-first platform in the crowded DeFi space.

1. Elevates Platform Security

De.Fi Scanner provides a comprehensive security assessment, identifying vulnerabilities in smart contracts, tokenomics, and governance. This proactive approach helps businesses safeguard their platform against potential attacks, reducing the chances of costly breaches or hacks.

2. Reduces Attack Vectors

The tool goes beyond static code analysis by detecting a wide range of potential attack vectors, such as reentrancy attacks, rug pulls, and unauthorized admin access. By catching these risks early, businesses can minimize their exposure to threats and protect their users from malicious activities.

3. Builds User Trust

Security is a top concern for users investing in DeFi platforms. By using De.Fi Scanner, businesses can demonstrate a commitment to safeguarding their users’ funds and data. This builds credibility and trust, encouraging users to engage more confidently with the platform.

4. Boosts Compliance Readiness

For businesses seeking VC funding or aiming for exchange listings, an audit of their smart contracts is often a requirement. De.Fi Scanner streamlines the audit process, ensuring that the platform meets the necessary security standards. This smoothens the path for funding and exchange listings, helping businesses stay competitive.

Benefits of Building a Smart Contract Scanner for Enterprises

Building a smart contract scanner like De.Fi helps enterprises identify risks early, so they can address issues before attacks happen. It also streamlines security checks, improves user protection, and boosts business trust by showing a commitment to safety.

1. Proactive Risk Identification

Building a smart contract scanner like De.Fi allows businesses to identify risks before they escalate into actual attacks. By detecting vulnerabilities early on, companies can fix issues proactively, reducing the chances of costly security breaches or hacks.

2. Automated Vulnerability Patching Suggestions

With AI-driven technology, the scanner can provide automated vulnerability patching suggestions. This feature accelerates the remediation process, helping developers implement fixes faster and more accurately, while reducing the risk of human error.

3. Behavioral Analysis of Tokens

Post-deployment, the scanner can continuously monitor token behavior, flagging any unusual or risky activities. By analyzing transaction patterns and smart contract interactions, businesses can quickly spot potential threats or malicious behavior that might have gone unnoticed otherwise.

4. Fast Security Due Diligence

When listing new tokens or integrating with third-party platforms, speed is key. A smart contract scanner streamlines security due diligence by quickly analyzing contracts, making it easier and faster for businesses to assess the security of potential partners and avoid risky integrations.

5. Seamless Integration into Developer Workflows

Integrating a smart contract scanner into a developer’s workflow through APIs or CI/CD pipelines ensures continuous security checks throughout the development process. This integration helps businesses maintain high security standards without disrupting ongoing development efforts.

6. Business Trust and Adoption

By building and showcasing a smart contract scanner, businesses demonstrate a strong commitment to security. This fosters trust among users, partners, and investors, ultimately boosting adoption and positioning the platform as a reliable, security-first player in the DeFi space.

How to Build a De.Fi-Like Smart Contract Scanner?

We understand the importance of security in the fast-paced world of DeFi and blockchain technology. We specialize in building custom smart contract scanners for our clients, similar to De.Fi, to ensure your platform remains secure and resilient against vulnerabilities and attacks. Here’s how we develop a smart contract scanner tailored to your needs:

1. Setting Up Multi-Chain Connectivity

We start by establishing multi-chain connectivity, ensuring your scanner works seamlessly across Ethereum, BNB, Polygon, and other blockchains. We use tools like JSON-RPC, Web3.js, and Ethers.js to connect to blockchain nodes, and can rely on services like Alchemy, Infura, or Moralis for efficient data retrieval.

2. Building Source Code & Bytecode Collector

Next, we build a system to collect contract data from reliable block explorers like Etherscan or BscScan. For contracts that aren’t verified, we implement decompilers and other techniques to handle obfuscated or missing code, ensuring that no contract is overlooked during analysis.

3. Implementing Vulnerability Analysis

We combine static and dynamic analysis to provide a comprehensive security review. Using symbolic execution and AST parsing, we identify code vulnerabilities, while also simulating transaction behavior to spot risks like rug pulls, backdoors, and potential exploits that can emerge at runtime.

4. Integrating Risk Scoring Engine

Once vulnerabilities are identified, we integrate a risk scoring engine that aggregates the findings into an overall severity score. This helps you prioritize which issues need immediate attention, categorizing them into risk levels like critical, high, medium, or low.

5. Designing a Report Generator

Our scanners provide easy-to-read reports that outline the findings in clear terms. These reports include detailed descriptions of each issue, severity ratings, suggested fixes, and specific warnings about risks such as honeypots, liquidity issues, and governance flaws, making it easier for you to take actionable steps.

6. APIs & Developer Integration Hooks

To make security checks part of your everyday workflow, we offer API integration and developer hooks for easy connection to your existing tools. Our plugins for GitHub Actions, GitLab, Jenkins, and IDE extensions for VS Code and Remix help streamline security testing as part of your CI/CD pipeline.

Common Challenges in Building a Smart Contract Scanner

After working with numerous clients, we’ve come to understand the common challenges that can arise when building a smart contract scanner. Here’s a look at some of those hurdles and how we’ve learned to overcome them:

Challenge 1: Unverified or Obfuscated Contracts

We’ve all run into unverified contracts that make it nearly impossible to analyze the source code. Some projects intentionally obfuscate their code to hide malicious intent.

How We Handle It:

• Bytecode Similarity Detection: We compare the unverified contract’s bytecode to known malicious patterns to spot potential risks. Tools like Ethers.js’s getDeployedBytecode() and decompilers like IDA Pro and Ghidra are key for this.
• Behavioral Heuristics as a Fallback: When we can’t read the code, we look at the transaction history. If we see issues like restricted sells (honeypots) or sudden liquidity withdrawals (rug pulls), we flag those contracts as high risk.

Challenge 2: High False Positives in Honeypot Detection

A lot of legitimate contracts, especially those with transaction fees or tax tokens—can trigger false positives, making it harder to spot real threats.

How We Handle It:

• Real Transaction Simulation: We simulate actual buys and sells on a forked chain, like Ganache, to see how the contract behaves in real-time. Tools like Tenderly and Hardhat Network are super helpful for this.
• Liquidity and Holder Distribution Checks: We cross-check with DEXTools and DexScreener APIs to look for tokens with locked liquidity and a fair distribution. A token with locked liquidity and many holders is much less likely to be a scam.

Pro Tip: We’ve learned that ignoring contracts with over a year of safe history can help reduce false positives.

Challenge 3: Governance & External Call Complexity

When contracts use proxies, delegate calls, or have DAO governance, the complexity goes up. This adds extra risk, like the potential for an admin to rug pull or for external dependencies (such as oracles) to become attack vectors.

How We Handle It:

• Proxy Pattern Tracking: We track proxy patterns (EIP-1967/EIP-1822) and scan their implementation contracts to detect any hidden risks. OpenZeppelin Defender is a great tool for this job.
• Admin Function Analysis: We list all functions controlled by the admin (like mint() and withdraw()) and flag any changes made without a timelock as critical risks.

Challenge 4: Multi-Chain Compatibility

Each blockchain, whether it’s Ethereum, Solana, or Cosmos, has its own unique architecture, which makes cross-chain scanning difficult.

How We Handle It:

• Abstracted Interaction Layers: We use generalized adapters like Chainlink CCIP and LayerZero to make cross-chain queries simpler and more reliable.
• Third-Party Indexing Tools: To make sense of multi-chain data, we rely on The Graph for historical data indexing and Covalent API for unified analytics across chains.

Example: We use custom RPC handlers to normalize data from both EVM and non-EVM chains, ensuring seamless cross-chain functionality.

Key Tools & APIs to Build a Smart Contract Scanner

Building a security tool like De.Fi Scanner requires a solid tech stack to efficiently scan and analyze smart contracts. Below is a breakdown of essential tools, APIs, and frameworks you’ll need to develop a high-quality scanner:

1. Blockchain Access & Indexing

To fetch and analyze smart contracts, you need reliable access to blockchain data:

Node Providers (RPC/API Access):

• Alchemy: High-performance node API for Ethereum and multi-chain networks.
• Infura: Reliable JSON-RPC endpoints for Ethereum and other EVM chains.
• QuickNode: Supports Ethereum, Solana, and various L1/L2 chains.
• Moralis: Unified API for transactions, logs, and token data.

Blockchain Indexing & Querying:

• The Graph: Indexes historical contract data through subgraphs for efficient querying.
• Covalent API: Unified multi-chain data, including balances, transactions, and logs.
• Etherscan/BscScan API: Fetch verified source code and ABI data.

Why It Matters: Efficient blockchain access is crucial for retrieving live contract data, ensuring your scanner operates quickly and accurately.

2. Static Code Analysis Tools

To identify vulnerabilities in smart contract source code and bytecode:

Open-Source Security Scanners:

Slither, Mythril, and Securify are key tools for static analysis. Slither detects issues like reentrancy and unchecked calls, Mythril analyzes EVM bytecode for vulnerabilities, and Securify checks overall contract security. These tools provide essential coverage for smart contract security.

Custom Rule Engines:

• Abstract Syntax Tree (AST) Parsers: For building custom checks based on your vulnerability detection needs.
• Semgrep for Solidity: Uses pattern matching to detect exploits in Solidity code.
  

Pro Tip: Combining static analysis with dynamic checks helps reduce false positives and ensures more accurate vulnerability detection.

3. Simulation Engines (Dynamic Analysis)

To test contracts in a controlled environment:

Key Use Case:Simulating transaction behaviors, like testing if a contract blocks selling (honeypot), ensures you can catch runtime issues that static analysis might miss.

4. Risk Scoring Frameworks

To quantify and categorize risks, you’ll need a way to assess the severity of vulnerabilities:

• Custom Heuristic Engines: Assign weighted scores to various vulnerabilities, helping you prioritize fixes.
• Chainalysis API: Useful for checking if addresses are linked to scams or previous hacks.
• De.Fi Score Modeling: Clone risk-assessment algorithms that categorize vulnerabilities as Critical, High, Medium, or Low.

Example: A contract with both reentrancy and admin risks could be flagged with a “Critical” score, prompting immediate attention.

5. Frontend & Reporting (UX)

For creating an intuitive, user-friendly experience:

Frontend Frameworks:

React + Tailwind CSS is perfect for building a sleek, interactive dashboard that allows users to easily view scan results with a clean, responsive design. Next.js comes in handy when server-side rendering (SSR) is needed for better performance or SEO, ensuring faster load times and improved search engine visibility for your application

PDF & Report Generation:

PDFKit (Node.js) allows you to generate downloadable audit reports for users, providing them with a clean, printable format. Puppeteer can then convert these HTML reports into PDF files, making it easier to distribute and share the audit results with clients or stakeholders.

Enterprise Need: For audit firms and exchanges, white-label reporting options provide the flexibility to brand and distribute security reports as needed.

6. AI/LLM Integration (Optional but Powerful)

Integrating AI can help automate the audit process and assist with code fixes:

• OpenAI GPT-4 / Anthropic Claude: These tools can suggest fixes for vulnerabilities and explain security issues.
• Custom Prompt Templates: Create templates that ask AI to explain vulnerabilities and provide code fixes. Example:
• LangChain: Connect AI models with your security database for more advanced analysis.

Future-Proofing: AI can reduce manual auditing workload by over 50%, speeding up the process and ensuring higher accuracy.

7. Additional Security Databases

Cross-referencing known threats helps strengthen your scanner:

• De.Fi REKT Database: Provides a historical record of exploit data.
• Immunefi Reports: Includes the latest bug disclosures and security research.
• National Vulnerability Database (NVD): Contains CVE entries for DeFi hacks and other vulnerabilities.

Use Case: Integrating a Scanner into a Token Launchpad

A top DeFi token launchpad came to us with a real issue: more than 30% of the token contracts being submitted had hidden risks like honeypots, rug pulls, or backdoors. Their users were losing money, and it was starting to hurt the platform’s reputation. It was clear they needed a solution fast.

Their Requirements:

• Automatically scan every submitted token before approval.
• Block high-risk contracts from launching.
• Provide clear audit reports to projects and investors.

The Solution: AI-Powered Smart Contract Scanning

We designed and implemented an AI-powered solution that could scan smart contracts quickly, efficiently, and accurately. Here’s how we approached it:

Step 1: Automated Scanning Trigger

The first step was to integrate the scanner into the token submission process. Whenever a new token contract was submitted, the scanner was automatically triggered. We integrated it seamlessly via a webhook or API, using providers like Moralis and QuickNode to fetch the necessary blockchain data in real time.

Step 2: Deep Contract Analysis

Next, the scanner performed a deep dive into each contract, looking for common issues like:

• Honeypot Risks: Could users sell after purchasing the token?
• Backdoor Minting: Could the owner mint unlimited tokens?
• Liquidity Issues: Was the liquidity pool locked, or could it be drained?
• Governance Threats: Was ownership too centralized?

Step 3: Risk Scoring & Decision Engine

Once the analysis was completed, the scanner would assign a risk score to each contract based on its findings:

Step 4: Transparent Reporting

We provided detailed, easy-to-understand reports that were delivered to project teams. These reports explained exactly what issues were found, how they could be fixed, and why they posed risks to users. Additionally, investors could see verified badges on trusted tokens, assuring them that the tokens had been thoroughly vetted.

The Results: A More Secure Launchpad

After implementing this solution, the results were dramatic and immediate. The platform became significantly safer for both token creators and investors, and the impact was reflected in key metrics:

Key Business Impacts:

• Protected Users: The scanner drastically reduced the number of scam tokens listed, preventing users from losing funds.
• Built Trust: The platform quickly became known as the “safest launchpad” in the DeFi space, attracting more users and projects.
• Attracted Better Projects: With the added security layer, more serious and credible projects preferred the launchpad for its transparent and thorough vetting process.

Conclusion

Building a smart contract scanner like De.Fi Scanner is more than just a technical necessity, it’s a crucial step in securing the future of your platform. As hacks and scams continue to rise, ensuring robust security is key to maintaining user trust, attracting investors, and ensuring long-term success. At Idea Usher, we specialize in helping businesses integrate these advanced security measures into their platforms, whether you’re a DeFi protocol, NFT marketplace, DAO tool, or token launchpad, safeguarding your users and strengthening your reputation.

Looking to Develop a Smart Contract Scanner Like De.Fi?

At Idea Usher, we specialize in developing a smart contract scanner tailored to your platform, similar to De.Fi’s, designed to detect vulnerabilities, block honeypots, and enhance security. Our solution ensures that every contract on your platform is thoroughly vetted, safeguarding your users and maintaining the integrity of your ecosystem.

Why Choose Us?

• 500,000+ Hours of Coding Expertise – Our team of ex-MAANG/FAANG engineers crafts robust security tools that stand the test of time.
• Custom AI-Powered Scanners – From static analysis to real-time threat detection, we customize solutions to meet your specific needs.
• Proven Web3 Success – We’ve helped exchanges, launchpads, and enterprises reduce fraud by over 90%. Check out our success stories.

Secure your users. Build trust. Stand out. Let us help you take your platform to the next level with industry-leading security.

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