objbit

A complete blockchain node,
written in pure Objective-C.

ObjBit is a Bitcoin-inspired proof-of-work chain — UTXO accounting, Merkle trees, difficulty retargeting, halving supply, an encrypted wallet, JSON-RPC daemon and a flicker-free terminal dashboard. Built with clang and a Makefile. Zero third-party dependencies. Local-only by design: it binds 127.0.0.1 exclusively and can never reach the real Bitcoin network.

##Everything a node should be

Six clean modules — crypto, core, consensus, storage, wallet, node — plus a CLI that treats your terminal like it matters.

Real consensus

Double-SHA-256 proof-of-work, smooth per-block difficulty retargeting to a 30-second block time, 21M-capped supply with halvings, longest-valid-chain selection with working reorgs.

Serious key hygiene

ECDSA P-256 via Security.framework, wallet encrypted at rest with AES-256-GCM under PBKDF2-HMAC-SHA256 (600k rounds), keys zeroized with memset_s, auto-locking, encrypted export/import.

Fast where it counts

~4 MH/s mining on Apple Silicon, blocks in seconds, instant startup with full re-validation of every stored block — the block log is the single source of truth.

Hostile-input paranoia

Every parser bounds-checked and poison-on-failure, overflow-checked 64-bit amount arithmetic, strict JSON-RPC schema validation, token auth with constant-time comparison, rate limits.

Verified, not asserted

220-check test suite with NIST/RFC vectors, every consensus rejection path, corruption-recovery tests and a spawned-daemon end-to-end flow — clean under ASan, UBSan and the clang static analyzer.

A terminal UI you’ll like

24-bit color, box-drawn tables, human amounts, relative timestamps, spinners, a live full-screen dashboard with zero flicker — and graceful plain output when piped.

##Thirty seconds in

Real captures from a fresh chain.

##Install

macOS on Apple Silicon. One command, no dependencies:

curl -fsSL https://kittyblur.com/downloads/objbit-1.0.0-macos-arm64.tar.gz -o objbit.tar.gz \
  && tar -xzf objbit.tar.gz && cd objbit-1.0.0-macos-arm64 && sudo ./install.sh

Then:

objbitd &              # start the local node (data in ~/.objbit)
objbit-cli newwallet   # create your encrypted wallet
objbit-cli mine 10     # mine your first blocks
objbit-cli dashboard   # watch the chain live — q to quit

Prefer building from source? make && make test with nothing but the Xcode Command Line Tools — see the docs. Binaries are not code-signed; macOS may quarantine the download (xattr -d com.apple.quarantine objbit.tar.gz).

##Downloads

v1.0.0 · MIT license · arm64 · 173 KB

FileSHA-256
objbit-1.0.0-macos-arm64.tar.gz cfa163f60c6d431a1e8e2ee1d52e8b333051da97aad8562e399898e5cacbbdee
SHA256SUMS checksum manifest

Verify before installing:

curl -fsSLO https://kittyblur.com/downloads/objbit-1.0.0-macos-arm64.tar.gz
curl -fsSLO https://kittyblur.com/downloads/SHA256SUMS
shasum -a 256 -c SHA256SUMS