Important
Security fork at block 431017 (11 September 2026). Doichain activated a security fork to restart the stalled chain and to close a serious security hole: the old software never checked a block's difficulty (nBits). All node operators, pools and exchanges should run v31.1.5. Check your node: doichain-cli getblockhash 431018 must return 71d50ff1…. Details and instructions: #16.
https://doichain.org
Doichain is a decentralized name and data registration blockchain. It is a fork
of Namecoin (which in turn derives from Bitcoin) and
therefore inherits Namecoin's naming system and merged mining, while adding the
name_doi operation for a simpler, ownership-controlled way to register names.
- Securely record and transfer arbitrary names (keys).
- Attach a value (data) to a name (up to 520 bytes).
- Register a name in a single step with
name_doi(see below). - Transact the Doichain currency (DOI).
- Merged mining and decentralized DNS, inherited from Namecoin.
Doichain is built on top of Namecoin Core, so most of the code, RPCs and tooling are identical. The Doichain-specific parts are:
- Own network. Doichain is a separate chain with its own genesis block,
network magic, default ports (P2P 8338 / RPC 8339), address prefixes,
dc…bech32 addresses and AuxPoW chain id0x0002. name_doi— one-step, UTXO-owned names. In addition to Namecoin's classic two-step registration (name_new→ wait →name_firstupdate, a commit/reveal that protects against front-running), Doichain adds theOP_NAME_DOIoperation: a name is registered in a single transaction, and afterwards it can only be changed by whoever controls it — proven by spending the name's previousname_doioutput (the same UTXO-ownership principle Namecoin uses forname_update). Classicd/Namecoin names keep working unchanged alongside it.
Register a name and a value in one step, read it back, then update it as the owner (this spends the previous output, so only the owner can do it):
# one-step registration
doichain-cli name_doi "id/alice" "hello from doichain"
# ...mine/confirm a block, then read it back
doichain-cli name_show "id/alice"
# owner update (fails for anyone who does not control the name)
doichain-cli name_doi "id/alice" "updated value"Doichain Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/license/MIT.
The master branch is regularly built (see doc/build-*.md for instructions) and
tested, but is not guaranteed to be completely stable.
Tags are created regularly to
indicate new official, stable release versions of Doichain Core.
Doichain Core tracks Namecoin Core and Bitcoin Core upstream; changes that are not Doichain-specific should ideally be contributed there. The contribution workflow is described in CONTRIBUTING.md and useful hints for developers can be found in doc/developer-notes.md.
This repository is based on the Namecoin Core release tagged nc31.1
(Bitcoin Core 31), and the full upstream history is preserved. The complete set
of Doichain-specific changes on top of that base can therefore be reviewed with:
git fetch --tags
git diff nc31.1..masteror on GitHub via
nc31.1...master.
Please discuss complicated or controversial changes as a GitHub issue before working on a patch set.
Testing and code review is the bottleneck for development; please help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.
Developers are strongly encouraged to write unit tests for
new code, and to submit new unit tests for old code. Unit tests can be compiled
and run (assuming they weren't disabled during the generation of the build system)
with: ctest. Further details on running and extending unit tests can be found in
/src/test/README.md.
There are also regression and integration tests, written in Python.
These tests can be run (if the test dependencies are installed) with:
build/test/functional/test_runner.py (assuming build is your build directory).
Continuous Integration runs via GitHub Actions (.github/workflows/ci.yml) on every push and pull request, building and testing on Linux, macOS and Windows and running the linters.
Changes should be tested by somebody other than the developer who wrote the code. This is especially important for large or high-risk changes. It is useful to add a test plan to the pull request description if testing the changes is not straightforward.
Translation workflow is not yet set up for Doichain Core. For strings which are common to Bitcoin Core, see below.
Changes to translations as well as new translations can be submitted to Bitcoin Core's Transifex page.
Translations are periodically pulled from Transifex and merged into the git repository. See the translation process for details on how this works.
Important: We do not accept translation changes as GitHub pull requests because the next pull from Transifex would automatically overwrite them again.