Open source webapps, useful utility tools, focused experiments and working products for the Kaspa ecosystem. Built on the blockDAG. Built for Kaspa. Built by KasBTC.

Explore developments What is HUB21?

Active developments

01 / NFTLive

KasNFT Nexus

An independent offer relay for Kaspa NFTs, built to make private NFT negotiation simple. Potential buyers can submit private, non-binding offers on NFTs, both listed and unlisted. Holders receive instant in-app and Telegram notifications, can counter, decline, or agree, and both sides can follow the offer flow from the dashboard or the NFT detail page with instant notifications. No funds are ever locked inside Nexus. It is entirely an offer extension for KaspaCom, not a marketplace. Offers are private and non-binding, and final settlement still happens publicly and safely on KaspaCom.
02 / ExplorerLive

All-in-One Kaspa Token Explorer

kashub.fyi is an all-in-one explorer for the token ecosystem, built to make KRC20, KRC721, KNS, L2 tokens, KCC20, wallets, portfolio tracking and market discovery easier to follow in one place. Track tokens with price, volume, holders, mint status, charts, transactions, and market data. Add tokens to your favorites to cancel the noise. Open any L1 or L2 wallet and view token holdings, transactions and labels. Labels can be added locally, exported, imported and reused across transaction and holder views. Our explorer also has a massive built-in portfolio tracking — completely login free! Everything stays locally in your browser and you can export and import your data.
03 / ToolingLive

Kaspa Dev Tools

A purpose-built and growing toolbox for Kaspa communities, analysts and project owners. Trace wallet interactions, clusters and suspicious relationship patterns and create interactive relationship graphs for Kaspa wallets with the Wallet X-Ray; generate KRC20 and KRC721 holder snapshots with custom minimums and/or combine multiple collections; send multiple KRC721 assets in a controlled sequence; and more.
04 / Protocol R&DExploring

Atomic NFT Batch Transfers

An experimental KRC721 indexer fork exploring protocol-level atomic batch transfers on Testnet 10. It moves 2 to 50 NFTs from one collection to one destination with one inscription, one wallet confirmation and one atomic ownership update. This build exists because the current KRC721 transfer operation moves only one NFT at a time, forcing larger selections through repeated wallet confirmations and separate commit-reveal transactions.
05 / IndexerLive

KCC20 Indexer

An independent mainnet indexer and public covenant data layer for KCC20 tokens on Kaspa. It tracks verified tokens, covenant history, holders, balances, UTXOs and decoded token actions from reorg-safe node data. Explore live network statistics and activity charts, inspect token supply and holders, follow new blocks in real time, or access the indexed data directly through the public API.
06 / NFT GamePrivate Beta

GothDAG

GOTHDAG is an idle game and NFT staking platform built around our Kasgoths and Kaszombies NFTs. Your collection works in the background while you build a gothic empire, earn EXP, craft rituals, compete with real players and collect KAS and KasBTC rewards. Designed as a low-maintenance experience, GOTHDAG focuses on idle gameplay, NFT utility, and long-term progression rather than endless grinding. All rewards are powered by our development-fueled reward engine called Teal Glow Injection.

07 / CovenantsOpen Beta

KasCoven Vaults

KasCoven Vaults explores programmable self-custody and true sovereignty directly on Kaspa. Create time-locked vaults that release assets only after a defined period, or dead-man-switch vaults that protect a beneficiary when the owner's pulse stops. Every condition is enforced by covenant architecture rather than a trusted intermediary. KasCoven Vaults are designed so the important recovery data is written into Kaspa transaction payloads. The website is a convenient interface, but it is not the only path to your funds.

08 / GamingBuilding

Kaspa Games

A platform built for real-time PvP, where every opponent is a real player and every victory is earned. Kaspa Games is not a gambling casino. Every included game is skill based, with no RNG during gameplay. Both players start with identical conditions. Every outcome is determined solely by decisions, strategy and execution. No pay-to-win mechanics.

09 / ProtocolBuilding

Project Sentinel

What if your assets had a mind of their own? Sentinel is a mathematical heartbeat — the silent observer that ensures your intentions are realized, even when you aren't there to command them. Shielded by architecture, governed by truth and immune to human error. Your digital legacy is no longer a static entry; it is a living, breathing intent.

10 / ApplicationBuilding

Kaspire

Kaspire is quietly taking shape as one of HUB21's next major projects. Its purpose, possibilities and full feature set remain behind the curtain while the foundations are being built. Some developments are better revealed when the time is right. The next era of ...... stay tuned ;-)

11 / Telegram BotLive

Kaspa Tip Bot

Kaspa Tip Bot is a Telegram tip bot with support for KAS, KRC20 tokens and KRC721 NFTs. Wallet keys are encrypted. You can even tip users who haven't connected to the new bot yet: it automatically creates a new wallet for the recipient, who only needs to connect with the bot in a private chat to claim their tips.
12 / Telegram BotLive

KRC20 Explorer Bot

A Telegram bot for tracking KRC20 operations. Monitor any KRC20 token in real time across transfers, listings and sends, with an optional minimum amount filter. Add the bot to your own KRC20 community to receive notifications for your token's operations directly in your Telegram group.
13 / Telegram BotLive

KaspaRaid Bot

A Telegram raid bot built by and for the Kaspa community. Unlike Raidar, KaspaRaid Bot is completely free of ads and shady links, and supports an unlimited number of raids running at the same time.
14 / Telegram BotLive

Kaspa Ticker

Tracking the Kaspa ecosystem effectively usually means keeping a dozen tabs open for charts, hashrates and mempool data. Kaspa Ticker solves that headache by delivering fast data and clear insights for everything Kaspa straight to Telegram. It provides real-time market data and charts, live tracking from major exchanges, ongoing updates on hashrate trends and mempool statistics, plus key insights and rapid updates whenever the market moves.
15 / Telegram BotsLive

Various Telegram Bots

We have developed many more Telegram bots for the Kaspa ecosystem and for a variety of other Kaspa projects. These include NFT auction bots, buy-alert bots, price tracking and chart-data bots, NFT presale bots, Telegram mini games and more — each built around the specific needs of its community or project.

HUB21 Made with for Kaspa.

HUB21 is the development space of KasBTC.

We turn ideas into useful, working tools. Over time, we're bringing more and more apps, tools, games and bots, including full support for Kaspa assets.

Are you a project owner and need custom developments? Whether it's useful utility tools, entertaining games, an app or website, our HUB21 has got you covered at very fair prices, with full payment only on delivery. Contact us via Telegram or Twitter.

Telegram Twitter GitHub