Ranju GC

A Byzantine fault-tolerant bridge, built from first principles

A working simulation of a cross-chain bridge in which nothing is trusted but an honest majority of each validator set. Assets move between two simulated chains through three independent BFT sets, source, bridge and destination, and an untrusted relayer that carries the quorum certificate but whose honesty the protocol never rests on. Each set runs n = 4, f = 1, so the quorum of 2f+1 is exactly what the honest validators can reach on their own.

Every decision in both legs bottoms out in a single quorum function that enforces four things at once: signers distinct, signers authorized, keys bound to registered identities, and all signatures over the same canonical digest. A cryptographically valid signature over the wrong message therefore never counts, which is what most bridge failures reduce to. 105 transaction attempts cover every adversarial case I could pose to it, Byzantine signers, a tampering relayer, replayed certificates, repeated-signature stuffing, and 46 tests assert the invariant that matters: every token circulating on the destination chain stays backed one for one by value locked on the source.

PythonEd25519BFT consensusquorum certificates46 tests

A production cross-chain bridge, with no trusted relayer

Most people still move value between chains by trusting a centralized exchange to custody their assets along the way. This bridge removes that intermediary, which is exactly what makes its security assumptions load-bearing. An M-of-N verifier set attests independently to what happened on the source chain, and the signatures themselves come from NEAR Chain Signatures, NEAR's own decentralized threshold-MPC network. We used theirs; we did not build an MPC of our own. It signs across both secp256k1 and ed25519 chains.

Operating it taught me that the hard problems are not in the code so much as in the protocol: what exactly is trusted, what an adversary controlling some of the verifiers can do, and how value moves atomically across chains that cannot see each other. The quorum at the top of this page is that verifier set, in miniature.

M-of-N attestationthreshold MPCsecp256k1ed25519GoRust

Cross-chain intent relay

The cloud-deployed relay behind the bridge. It processes user transactions across heterogeneous chains, with modular per-chain deployments and infrastructure provisioned as code.

AWS LambdaSQS and SNSDynamoDBTerraformDocker

Sodax: cross-chain DeFi protocol architecture

Smart-contract architecture for a production hub-and-spoke money market and cross-chain swaps, with solver and executor services that route and settle user intents through the bridge above.

SolidityRustEVMNEARStellar

Multisig coordination tooling

A Go backend that coordinates multisig transaction proposals across chains, with wallet applications for Stellar and NEAR and a CLI for invoking contract methods on any of them. On-chain safety mechanisms including circuit breakers.

Gomultisigcontract auditing

Shruti: a Nepali audiobook reader

An end-to-end mobile application built on the Tacotron2 Nepali TTS system, carrying the research through to something a reader can actually listen to. The accompanying dataset is publicly released on OpenSLR. Training-data scarcity, and what it does to intelligibility, is characterized with word error rate, spectrogram inspection, and crowd-sourced mean opinion scores.

PyTorchTacotron2HiFi-GANrepository