BitGrin

BitGrin is a Mimblewimble-based, proof-of-work cryptocurrency launched in January 2019 as a fork of the Grin codebase. It aimed to pair Mimblewimble’s privacy and scalability with a “Bitcoin-like” monetary policy, implemented in Rust and released under the Apache-2.0 licence. The public repository describes one-minute block targets, Cuckoo Cycle family PoW (Cuckaroo and Cuckatoo variants), decreasing block rewards, and transaction fees tied to outputs and overall transaction size.

Third-party profiles summarise the project’s stated supply policy as a capped maximum of 21,000,000 XBG (“Bitcoin economics”) and classify the consensus as PoW using Cuckoo Cycle.

Monetary policy: BitGrin’s documentation calls out “Bitcoin economics” with decreasing block rewards over time. External reference sites record a 21 million XBG supply cap as the project’s stated target, distinguishing it from Grin’s linear emission. (BitGrin’s repositories describe the declining subsidy but do not, in the README, enumerate the full schedule.)

Development & release status: The core repository shows v2.0.6 as the latest tagged release on 11 February 2020. Public activity across the organisation’s repos concentrates around 2019–2020; there is no evidence of recent maintenance.

Notable events (supply anomaly, 2020): On 4 June 2020, multiple outlets noted reports that billions of XBG were minted on the network despite the stated 21M cap. Coverage appears on Cointelegraph and related syndications, and a contemporaneous Medium post alleged a protocol-level exploit. These are third-party reports; no corrective release is published in the project’s GitHub.

Public listings attribute BitGrin’s launch (31 January 2019) to an anonymous developer team; no maintainers are named in the core repositories.

Key facts:

• Codebase: Rust; fork of mimblewimble/grin; Apache-2.0 licence
• Protocol: Mimblewimble; confidential amounts; cut-through
• Consensus: PoW (Cuckaroo/Cuckatoo); ~1-minute blocks
• Claimed supply policy: capped at 21,000,000 XBG with decreasing rewards (per third-party summaries and project tagline)
• Status: last tagged release Feb 2020; later reports flagged a supply-minting anomaly in mid-2020