Development based on TON enables fantastic speed and reach for Telegram users, but many builders face the same hidden obstacles. TON is positioned as a "superchain", designed for mass implementation, and is capable of supporting millions of transactions per second at low cost through dynamic sharding technology that divides the blockchain into smaller pieces of parallel processing.
This makes TON highly suitable for data-intensive applications such as gaming and DeFi. In this article, we outline the eight most common and costly mistakes TON developers are making today, from misunderstanding the FunC actor model and asynchronous messaging to writing code that consumes excessive gas and exhausts users.
What is TON and Why It's Gaining Traction in 2026
The Open Network is a high-throughput, layer-1 blockchain for large-scale workflows, supporting flexible sharding, sub-second transaction completion, and transaction fees under 1 cent.
By providing Mini Apps and built-in USDT support, deep integration with the Telegram ecosystem enables developers to reach almost a billion users without requiring additional wallet installation. In 2026, TON's popularity exploded due to tap-to-earn games, DeFi TVL, and the steady influx of users who are not natively familiar with cryptocurrency.
TON's Ecosystem Core Components
Open Network is a rapid, cost-effective network designed to perform well on Telegram for regular customers. All of its components are straightforward, affordable, and powerful enough to serve hundreds of thousands of users simultaneously. Here is a simple explanation of the main components.
TON Blockchain
Smart contracts are developed in FunC and run on the TON Virtual Machine (TVM). They conclude in less than a second and cost less than a penny. Meanwhile, Proof-of-Stake is used by thousands of validators to guarantee security.
Toncoin (TON)
A local cryptocurrency that covers all network expenses. You can use it to make quick payments, stake, vote on governance matters, and pay for gas. DeFi, NFT issuance, and play-to-earn games are also powered by it. Fees are slowly burned by supply, which could eventually raise their worth.
TON DNS
It substitutes short names for the long wallet addresses. Errors are almost eliminated because users enter a name rather than copying 48 random characters. No one can ever take your name because ownership is recorded on the chain.
TON Storage
It is a blockchain-based, decentralized file storage solution comparable to Dropbox or Google Drive. Once you pay the charge and download the file, it is permanently saved. For security, files are divided into segments, encrypted, and backed up on several nodes. Ideal for storing backups, documents, game assets, and NFT images.
TON Proxy
It hides your real IP address and safeguards your personal information while using TON. Traffic passes through several random nodes, just like a built-in VPN. It protects against network tracking, spying, and DDoS attacks. It also makes anonymous voting, payments, and web browsing easy for everyone.
Telegram Integration
TON is fully integrated into Telegram — no third-party apps or complex setup required. Wallets, payments, games, and shops are just a tap away in any chat. Mini-apps operate directly within Telegram and already have over 900 million potential users.
Key Benefits of Developing on TON
The potential to serve millions of customers at the lowest cost and with the fastest confirmation, without investing in customer acquisition, is enabled by building on TON. These five key characteristics set TON apart from the others.
- Massive built-in user base via Telegram integration
Your game or dApp can appear as a mini-app directly in Telegram chats, accessible to more than 900 million regular users each month. There are no marketing expenses because the platform's integrated distribution system handles them. This is the simplest method to attract new users in the current Bitcoin landscape.
- Extremely low transaction fees & high speed
However, even during periods of high volume, typical TON transactions cost less than $0.01 and are executed in less than a second. With its autonomous network scaling, dynamic sharding avoids the congestion and price spikes experienced by Ethereum and Solana. Without experiencing any fees, users can exchange tokens in different ways or perform hundreds of gaming operations.
- Developer-friendly tools and languages
FunC features C-like syntax, built-in continuous storage, and asynchronous messaging, providing intuitive smart contract logic. TON Blueprint and Toniq enable one-click project creation, local testing, and rapid test network expansion. Excellent documentation, active Discord support, and prebuilt libraries significantly accelerate development.
- Strong economic incentives & ecosystem funding
The TON Foundation and Telegram organize regular hackathons with prize funds of up to $5 million and grant programs that typically award sums between $50,000 and $500,000. The best projects will receive free direct marketing support on Telegram for millions of users. Successful teams can often secure more funding faster because they have real user numbers from day one.
- Seamless wallet experience with TON Connect
Using a simple QR code or deep link, TON Connect connects any wallet to your dApp without any extensions or approvals. Users sign transactions in their familiar wallet app and immediately return to your mini-app. Registration takes just a few seconds and works the same as on a standard website.
Common Mistakes in TON Smart Contract Development
Its architecture is so different from Ethereum or Solana that even seasoned blockchain developers often fall into TON-specific traps without proper guidance. The most dangerous and common ones, along with the clearest solutions to avoid them, are provided below.
Ignoring asynchronous execution models
Because messages are actually asynchronous, many developers write FunC code as if they were synchronous; this can lead to deadlocks, funds being lost, or contracts freezing if responses never arrive. If your contract expects immediate return values or creates loops that wait for external messages, it will freeze permanently.
How to Avoid: Use the seqno and replay-protection patterns to test each thread with the local Blueprint simulator, never assuming an operation is complete simply because you have sent a message.
Underestimating gas fees and optimization
The commissions are so small (~$0.005) that newcomers often forget to optimize, write superfluous, bloated loops, or store unnecessary data, and end up having contracts that are 10–100 times more costly than they need to be. Unoptimized code also contributes to ever-growing storage costs.
How to Avoid: Profile every contract using either toncli or Blueprint's gas reporter from day one. Keep dictionaries as small as possible, develop strategies to avoid redundant calculations, use bit lines efficiently, and prefer computation over storage.
Poor handling of TON's sharding architecture
Developers treat all of the accounts as if they were permanently on one shard and frequently send messages with the wrong worker chain or shard ID, which quietly fail or bounce the transaction. Hard-coding addresses without any check for shard migration is a direct path to token loss.
How to Avoid: Always use the latest address from get-methods or the Open Network Center API before sending. Use the official TON SDK's routing capabilities and enable replay protection with seqno + timestamp. Never store shard details in cache for more than a few minutes.
Errors in TON dApp Integration and Frontend Development
Though a smart contract may be a perfect solution, many TON dApps encounter issues at the interface and Telegram Mini-App levels, often due to inadequate support from a TON development company, leading to user losses, safety incidents, and negative feedback. Here are the three biggest and most expensive mistakes developers are still making.
Failing to secure Telegram Mini-App connections
Most of these teams use simple HTTP callbacks, allowing attackers to impersonate users and empty their wallets. Session hijacking via MITM on public Wi-Fi also happens quite often when developers skip verification.
How to Avoid: Always check initData on your servers using an official Telegram bot token and HMAC-SHA256 verification (code examples are available in the TON documentation). Use only TON Connect v2 with encrypted signatures and never use raw private keys.
Neglecting cross-device compatibility
Developers test only on their iPhones or Android devices and then forget that Telegram also exists on desktop computers, iPads, older Android devices, and eventually in web chats. The layout breaks, buttons become unavailable, the viewport height is calculated incorrectly, and haptic feedback breaks in some versions.
How to Avoid: Test on real iOS, Android, desktop, and web versions from day one. Use Telegram's built-in themeParams for automatic dark/light mode switching and safe embeds. Tools like BrowserStack or Telegram's own preview bot help you detect 90% of issues early on.
Overlooking data privacy in user interactions
Most of these mini-apps send wallet addresses, payment history, or chat IDs to analytics or third-party servers without the user's permission. This violates Telegram's strict confidentiality policy and could lead to the app being banned.
How to Avoid: Anonymize analytics by using Plausible or self-hosted Umami. Only show the shortened address, like abc, and let users copy the full address when relevant. Make sure to follow Telegram's requirements for mini-app privacy to avoid your application being instantly rejected during review.
Deployment and Security Pitfalls in TON Projects
Many open network applications lose funds or fail permanently, not because of sophisticated vulnerabilities, but because teams rush deployment and treat safety as an afterthought. In 2025–2026, the same three mistakes are repeated in the analysis of hacker incidents and failed launches, often occurring during critical transaction phases.
Skipping comprehensive testing environments
Developers will most often deploy directly from the Blueprint local network onto the main network, having never interacted with the public test network. In this way, real-world shard-splitting issues, message bounces, and differences in gas fees hit them post-launch. In many cases, projects that work on a local network but fail silently on the main network can never recover.
How to Avoid: Always do a full cycle on the official TON test network with real faucets and at least 24 hours of stress testing. Then use toncli local-testnet with enforced shard splitting, deploying the same bytecode to the public test network.
Vulnerability to common attacks like reentrancy
Teams are deploying immutable contracts with no admin key or proxy, only to find, multiple weeks later, that there are critical bugs with no way to pause or update the contract. Due to a lack of off-chain monitoring, when funds get drained or contracts become stuck, the only notice is when users cry out in Telegram groups.
How to Avoid: Use a transparent proxy template or embed a trusted multi-signature owner who can pause or refresh the contract. Add an emergency withdrawal function protected by a 5-of-8 multisig and test it on testnet. Plan for the ability to upgrade before your first deployment; you won't be able to add later.
Inadequate monitoring and upgradability planning
Although the asynchronous TON model complicates the classic Ethereum-style reentrancy, developers can still create dangerous patterns by rendering external messages before updating the state. In 2025, several DeFi projects lost millions due to reentrancy, despite “being aware” of the issue.
How to Avoid: Strictly follow the “check-effect-interaction” principle: first make the state changes, then send outgoing messages. Immediately mark the processed messages with seqno + bitflags and reject duplicates.
Best Practices for Successful TON Development
To build successful projects on The Open Network, you need to follow proven rules that leading teams use every day. These ten practices are designed to help you build apps that are fast, secure, and user-experienced, just like the ones that millions of Telegram users enjoy.
- Start with Blueprint + public testnet: Never implement on the mainnet without a complete Blueprint and at least 48 hours on the public testnet. Test all edge events (rebounds, shard splits, seqno collisions) with actual wallets.
- Optimize for storage first, compute second: Storage fees are permanent and accumulate indefinitely. Keep your vocabulary small, delete inactive entries, and use bit strings efficiently. A 10-kilobyte contract can cost $500 per year if you are careless.
- Implement proper upgradability or a pause from day zero: which can suspend critical functions. You will not be allowed to add this to TON later. Use a simple proxy server or a multi-signature holder (5 out of 8).
- Validate initData server-side every time: In mini-apps, do not believe anything from the user interface. Authenticate HMAC-SHA256 with the bot token on every single request and reject anything older than 30 minutes.
Final through
Generally speaking, developing on TON offers unprecedented opportunities for scalability and performance, especially when combined with Telegram. At the same time, these advantages are unique architectural concerns that demand special attention to asynchronous execution, gas optimization, sharding, and strong safety measures.
Understanding and proactively neutralizing the most common mistakes in TON development can help any community avoid costly errors and build reliable, high-performance applications. With the right approach, anyone can unlock the full potential of The Open Network and create solutions that connect millions of users worldwide.
