Nighthawk Wallet (DarkFi Edition) — Android

Privacy-preserving wallet (work-in-progress) by Nighthawk Apps. This tree ships as a new Android application id on the DarkFi network (DRK). The app integrates a native DarkFi wallet API via UniFFI (rust/darkfi-mobile-ffi → generated Kotlin + DarkfiMobileFfiApi) for chain sync, broadcast, and chat.

Download

Store listings are not finalized for com.nighthawkwallet.android. Placeholder targets until publishing completes:

F-Droid: DarkFi testnet package com.nighthawkwallet.android.testnet / flavor darkfitestnet (see docs/fdroid.md; listing pending fdroiddata merge). Legacy Zcash: com.nighthawkapps.wallet.android
Google Play: https://PLACEHOLDER_PLAY_STORE_LISTING_URL

Replace these URLs when production listings exist—do not invent live links prematurely.

Quick start

From the repository root (first-time or after vendored DarkFi / native code changes):

# 1) Pin upstream DarkFi
./scripts/vendor-darkfi.sh

# 2) Android SDK + NDK
export ANDROID_HOME="$HOME/Library/Android/sdk"
export ANDROID_NDK_HOME="$ANDROID_HOME/ndk/26.1.10909125"
export PATH="$PATH:$ANDROID_HOME/platform-tools"

# 3) UniFFI wallet native lib + Kotlin bindings
./scripts/build-darkfi-mobile-ffi-android.sh
# Emulator-only ABIs (faster):
# MOBILE_FFI_ABIS="arm64-v8a x86_64" ./scripts/build-darkfi-mobile-ffi-android.sh

# 4) Install
./gradlew :app:installDarkfimainnetDebug
# Testnet (side-by-side .testnet package):
# ./gradlew :app:installDarkfitestnetDebug

# 5) Quick checks
./gradlew :darkfi-android-sdk:testDebugUnitTest

Local lightwalletd: run sibling darkfi-lightwalletd on 127.0.0.1:9067 (cleartext loopback OK without pin). Public servers need TLS + pin — see Privacy & security and ../darkfi-lightwalletd/docs/TLS_PINNING.md.

Chat: open the Chat tab — DarkIRC runs in-process via UniFFI (start_darkirc), not a desktop IRC server. First P2P/DAG sync can take several minutes. Watch adb logcat -s darkfi-mobile-ffi darkfi-net. Enable Tor in chat settings for SOCKS-routed P2P.

After editing darkfi_mobile_ffi.udl: re-run ./scripts/build-darkfi-mobile-ffi-android.sh. A UDL mismatch often shows as Unresolved reference 'SyncMethod'.

Disk: third_party/darkfi/target/ and rust/target/ grow large; cargo clean frees space between rebuilds.

Optional binaries: ./scripts/build-darkirc-android.sh (legacy darkirc_exec), ./scripts/build-darkfid-android.sh.

IDE setup, emulators, signing, and troubleshooting: Setup Documentation.

Repository layout

parent/
  darkfi/                    # optional; app vendors into third_party/darkfi
  darkfi-lightwalletd/       # gRPC lightwalletd (local sync target)
  darkfi-mobile-ffi/         # optional sibling symlink of rust/darkfi-mobile-ffi
  nighthawk-android-wallet/  # this repo (GitHub: nighthawk-apps/nighthawk-android-wallet)
  nighthawk-ios-wallet/
  nighthawk-desktop/
  moonshine/

Vendored DarkFi is not committed — run ./scripts/vendor-darkfi.sh after clone. The shared UniFFI crate lives at rust/darkfi-mobile-ffi. Other clients (desktop, etc.) may symlink or copy it to a sibling directory named darkfi-mobile-ffi.

Prerequisites

Requirement	Notes
JDK 17+	Temurin common; Gradle may use toolchains — see Setup
Android SDK	SDK Manager → set `ANDROID_HOME`; add `platform-tools` to `PATH` for `adb`
Android NDK	`$ANDROID_HOME/ndk/<version>`; set `ANDROID_NDK_HOME` for `cargo-ndk`
Rust + Cargo	rustup stable
`cargo-ndk`	`cargo install cargo-ndk`
Android Rust targets	See command below
Vendored DarkFi	`./scripts/vendor-darkfi.sh` (pins `docs/upstream/darkfi-revision.txt`)

rustup target add aarch64-linux-android armv7-linux-androideabi i686-linux-android x86_64-linux-android

Build

UniFFI native libraries

Produces libdarkfi_mobile_ffi.so per ABI, copies into artifacts/mobile-ffi/ and darkfi-android-sdk/src/main/jniLibs/, and regenerates Kotlin bindings from rust/darkfi-mobile-ffi/src/darkfi_mobile_ffi.udl.

export ANDROID_NDK_HOME=/path/to/ndk   # e.g. ~/Library/Android/sdk/ndk/26.1.10909125
./scripts/build-darkfi-mobile-ffi-android.sh

# Emulator + device only:
# MOBILE_FFI_ABIS="arm64-v8a x86_64" ./scripts/build-darkfi-mobile-ffi-android.sh

Re-run whenever Rust sources or the UDL change. If matching .so files already exist in artifacts/mobile-ffi / jniLibs, Gradle alone is enough until the next Rust/UDL change.

Manual cargo-ndk copy (equivalent to the script)

export ANDROID_NDK_HOME
cd rust
cargo ndk \
  -t arm64-v8a -t armeabi-v7a -t x86 -t x86_64 \
  build --release -p darkfi-mobile-ffi

JNILIBS=../darkfi-android-sdk/src/main/jniLibs
T=target
mkdir -p "$JNILIBS/arm64-v8a" "$JNILIBS/armeabi-v7a" "$JNILIBS/x86" "$JNILIBS/x86_64"
cp "$T/aarch64-linux-android/release/libdarkfi_mobile_ffi.so"   "$JNILIBS/arm64-v8a/"
cp "$T/armv7-linux-androideabi/release/libdarkfi_mobile_ffi.so" "$JNILIBS/armeabi-v7a/"
cp "$T/i686-linux-android/release/libdarkfi_mobile_ffi.so"       "$JNILIBS/x86/"
cp "$T/x86_64-linux-android/release/libdarkfi_mobile_ffi.so"   "$JNILIBS/x86_64/"
cd ..

Crate details: rust/darkfi-mobile-ffi/README.md.
Feature catalog: docs/app-features.md · Plan: docs/implementation-plan.md.

Android app

# Mainnet debug
./gradlew :app:assembleDarkfimainnetDebug

# Testnet debug (distinct applicationId `.testnet`)
./gradlew :app:assembleDarkfitestnetDebug

./gradlew assembleDebug

# Release (keystore required — see docs/Setup.md)
# ./gradlew :app:assembleDarkfimainnetRelease
# Remote HTTPS requires TLS pin:
# ./gradlew :app:assembleDarkfimainnetRelease -PLIGHTWALLET_TLS_PIN_SHA256=<64hex>

APKs under app/build/outputs/apk/. Install:

./gradlew :app:installDarkfimainnetDebug
# or: adb install -r app/build/outputs/apk/darkfimainnet/debug/app-darkfimainnet-debug.apk

Chat (DarkIRC / EventGraph)

In-app Chat uses a native in-process DarkIRC daemon over UniFFI (start_darkirc). See DarkIRC embedded Android and DarkFi integration.

Capability	Behavior
Transport	EventGraph P2P via `libdarkfi_mobile_ffi.so` (clearnet `tcp+tls` seeds by default)
Tor	Chat settings → P2P via embedded Guardian `tor-android` SOCKS5; UI Connected (Tor) only after a real handshake
Public channels	`#dev`, `#random`, `#lunardao`, `#hackers`
E2E DMs	ChaCha via `chacha_encrypt_dm` / `chacha_decrypt_dm`
Status	`darkirc_status()` → `ConnectedDirect` or `ConnectedViaTor`
DAG history	First P2P connect can take several minutes
Settings	Settings → Chat — identity, Tor/SOCKS, DAG hours
Legacy path	Optional packaged `darkirc_exec` (not default)

./scripts/build-darkfi-mobile-ffi-android.sh
./gradlew :darkfi-android-sdk:testDebugUnitTest
./gradlew :app:installDarkfimainnetDebug

Manual smoke tests: DarkIRC chat on Android.

Architecture

UI: ui-lib Compose — onboarding, backup, restore, send, receive, settings, chat. Bottom nav: Chat → Wallet → Transfer → Settings (opens on Chat).
Themes: Stealth (default), Light, Midnight (APP_THEME_VARIANT).
Settings: identity (IRC nickname / chat public ID / gated secret), Tor, chat, server, security, about.
Wallet SDK: darkfi-android-sdk — PersistableDarkfiWallet, DarkfiMnemonic (22-word), DarkfiWalletCoordinator, DarkfiSynchronizer.
Balance: single confirmed/spendable DRK tally (no transparent/shielded split).
RPC presets: DarkfiEndpoint defaults to lightwalletd tcp://127.0.0.1:9067 (both networks). Network identity is enforced via GetLightInfo.chain_name.
Native: UniFFI + JNA → libdarkfi_mobile_ffi.so in jniLibs/<abi>/. Rebuild after rust/darkfi-mobile-ffi changes — DarkFi integration.

UniFFI & native bridge

Piece	Role
`rust/darkfi-mobile-ffi`	UniFFI `cdylib` (`darkfi_mobile_ffi.udl`) — crate README
Generated Kotlin	`com.nighthawkapps.lib.uniffi.darkfi_mobile_ffi` (via build script)
`DarkfiMobileFfiApi`	Stable façade so UI avoids importing generated symbols
`rust/darkfi-android-bridge`	Legacy minimal bridge — prefer `darkfi-mobile-ffi`
JNA	UniFFI 0.31 Kotlin bindings (`net.java.dev.jna:jna`)
`jniLibs/`	Per-ABI `.so` — Gradle does not invoke Cargo automatically

Privacy & security

The wallet talks only to darkfi-lightwalletd (never production darkfid). Sibling docs: darkfi-lightwalletd · TLS pin: docs/TLS_PINNING.md.

TLS pin (remote HTTPS)

openssl x509 -in lightwalletd.crt -outform DER | openssl dgst -sha256 -hex
# → 64 hex chars

./gradlew :app:assembleDarkfimainnetRelease -PLIGHTWALLET_TLS_PIN_SHA256=<64hex>
# or gradle.properties: LIGHTWALLET_TLS_PIN_SHA256=<64hex>

Manifest meta: com.nighthawkapps.lightwallet_tls_pin_sha256
Runtime override: SharedPreferences darkfi_lightwallet_security / lightwallet_tls_pin_sha256
Loopback http://127.0.0.1:9067 may omit the pin; remote https:// / tcp+tls:// fail closed without it

Tor (SOCKS5)

Enable Tor in settings. The SDK rewrites the lightwallet URL to socks5://proxy/dest; Rust dials via SOCKS5. Remote cleartext is only allowed through SOCKS; remote HTTPS still needs a TLS pin.

Sync & network

#	Feature	Status	Description
1	No direct darkfid	✅	`direct-darkfid` off in production
2	Block range padding	✅	Power-of-2 buckets (min 1024)
3	Polling jitter	✅	±30% sync intervals
4	TLS pin (S8)	✅	Leaf-cert SHA-256
5	Cleartext loopback only	✅	Non-loopback `http://` refused
6	OMR-first + backoff (S15)	✅	Exponential backoff; trial at max failures
7	Tor SOCKS5 dial	✅	`socks5://` for lightwallet gRPC
8	Reorg recovery (R1)	✅	`rewind_to_height()`
9	Tip regression (R4)	✅	`new_tip < prev_tip` triggers reorg
10	Server switch reset	✅	Clears tip / OMR counters

Data-at-rest & logging

#	Feature	Status	Description
8	Wallet pass	✅	Encrypted DataStore (`DrkWalletPassStore`)
9	Encrypted memo (RAM)	✅	Session keystream; not on disk
10	Log redaction	✅	`redact_sync_error()`

UnifOMR (scheme 0x05)

Requires darkfi-lightwalletd with fhe-omr
Crypto parity: RLWE n=1024, signed AHE, CLUE_ERROR_BOUND=2, length-prefixed SealPIR limbs
Flow: RegisterCluePublicKey → GetClue → SendTransaction(omr_clue) → GetUnifOmrDigest → FetchPirBatch
Sync fail-closed if clue PK registration fails; send uses LWD SendTransaction only (24h clue hint)
Trial-decrypt fallback (default on): when UnifOMR returns no matches (or large gaps), the wallet supplemental trial-decrypts compact blocks so you can receive from non-UnifOMR wallets such as upstream drk. Toggle Strict UnifOMR sync under Advanced settings to disable this (UnifOMR-only, more private / faster when counterparties also use UnifOMR).
Default local endpoint: http://127.0.0.1:9067
Limits: doc/unifomr_mvp_limits.md

#	Feature	Status
11	UnifOMR only (`0x05`; no PerfOMR)	✅
12	FHE any-match client path	✅
13	Multi-pubkey (cap 16)	✅
14	BFV query LRU (cap 16)	✅
15	Hard-fail digest (S11)	✅
16	Tip completeness (S24)	✅
17	Nullifiers all blocks (S25)	✅
18	SendTransaction + clue	✅
19	Domain-separated KDF	✅
20	Pool-based key delivery	❌
21	Cross-wallet trial fallback	✅
22	`SyncFallbackReason` via UniFFI	✅
23	Inter-match gap scanning	✅
24	Reorg callback	✅
25	LWD-only (`darkfidRpcUrl` default null)	✅
26	Wallet Tor bootstrap flag	✅
27	DM keypair UniFFI	✅
28	`chain_name` network guard	✅

What the server learns

Sync mode	Learns	Does not learn
UnifOMR	Encrypted digest + PIR window; clue-PK lookups	Which notes decrypt, spend keys
Trial / gap	Padded / gap ranges	Which notes decrypt
Direct darkfid ⚠️	Everything	(disabled — leave `darkfidRpcUrl` unset)

Sync modes

Mode	When	Privacy	Bandwidth
UnifOMR (0x05)	Server advertises `unifomr`	Best (MVP limits)	Low–medium
Trial (LWD)	After OMR failure / empty match	Degraded	Higher
Direct darkfid	Dev feature only	Poor	Highest

Code: rust/darkfi-mobile-ffi/src/{sync,lightwallet_client,lightwallet_sync,omr,unifomr,transactions,block_cache}.rs
Checklist: docs/verification-checklist.md.

Verification

Mirrors .github/workflows/pull-request.yml where tooling resolves:

Step	Command
JVM libraries	`./gradlew :configuration-api-lib:check :preference-api-lib:check :spackle-lib:check`
Wallet SDK unit tests	`./gradlew :darkfi-android-sdk:testDebugUnitTest`
Repo JVM tests	`./gradlew test`
Mainnet debug APK	`./gradlew :app:assembleDarkfimainnetDebug`
Android Lint	`ORG_GRADLE_PROJECT_IS_MINIFY_ENABLED=false ./gradlew :app:lintDarkfimainnetRelease`
ktlint	`./gradlew ktlint` / `./gradlew ktlintFormat`

Notes:

./gradlew checkProperties validates signing-related props (CI/release defaults).
ktlint uses com.pinterest.ktlint:ktlint-cli (KTLINT_VERSION in gradle.properties).
./gradlew detektAll runs in CI; a clean pass needs backlog clearance.

Known issues

Intel machines may need WALLET_IS_DEPENDENCY_LOCKING_ENABLED=false in ~/.gradle/gradle.properties if locking flakes during IDE sync.
Gradle may warn about mixed AGP detection for composite builds—safe when versions match under build-conventions-*.
IS_ANDROID_INSTRUMENTATION_TEST_COVERAGE_ENABLED prevents interactive debugging of the debug APK (CI-only).
Compose + Jacoco coverage remains limited upstream.

Install & shortcuts

This tree does not migrate data from older package IDs—restore from seed if needed.
shortcuts.xml hard-codes android:targetPackage="com.nighthawkwallet.android" (no ${applicationId} substitution). Avoid shipping mismatched testnet shortcuts silently.

Related projects

Sibling directory	Role
`../darkfi-lightwalletd`	Compact-block / UnifOMR gRPC server
`../darkfi-mobile-ffi`	Optional sibling name for the UniFFI crate (`rust/darkfi-mobile-ffi`)
`../nighthawk-ios-wallet`	iOS wallet
`../nighthawk-desktop`	Desktop wallet (Tauri)
`../moonshine`	CLI light wallet

Contributing & support

Guidelines: Contributing
Translations: Crowdin
Security: GitHub Security Advisories or maintainer channels. Do not disclose publicly before coordinated disclosure.
Issues / features: GitHub issues on this repository
Support: DM @NighthawkWallet on X
Email: nighthawkwallet@protonmail.com

Disclaimers

Funding/on-ramp and third-party exchange shortcuts were removed; acquire DRK through channels you trust.
Chat uses an in-process EventGraph daemon via UniFFI; optional Tor routes P2P through embedded tor-android SOCKS5.
Fiat hints depend on public APIs (COIN_GECKO_ASSET_ID) and may be unavailable.

Name		Name	Last commit message	Last commit date
.github		.github
.idea		.idea
app		app
artifacts		artifacts
build-conventions-stealth		build-conventions-stealth
build-info-lib		build-info-lib
buildSrc		buildSrc
configuration-api-lib		configuration-api-lib
configuration-impl-android-lib		configuration-impl-android-lib
darkfi-android-sdk		darkfi-android-sdk
docs		docs
fastlane		fastlane
gradle		gradle
nighthawk-ios-wallet		nighthawk-ios-wallet
preference-api-lib		preference-api-lib
preference-impl-android-lib		preference-impl-android-lib
rust		rust
scripts		scripts
spackle-android-lib		spackle-android-lib
spackle-lib		spackle-lib
test-lib		test-lib
third_party		third_party
tools		tools
ui-benchmark-test		ui-benchmark-test
ui-design-lib		ui-design-lib
ui-integration-test		ui-integration-test
ui-lib		ui-lib
ui-screenshot-test		ui-screenshot-test
.gitignore		.gitignore
AI_INSTRUCTIONS.md		AI_INSTRUCTIONS.md
CODE_REVIEW_GUIDELINES.md		CODE_REVIEW_GUIDELINES.md
CONDUCT.md		CONDUCT.md
CONTRIBUTING.md		CONTRIBUTING.md
CONTRIBUTING_AI.md		CONTRIBUTING_AI.md
Gemfile		Gemfile
LICENSE		LICENSE
README.md		README.md
build.gradle.kts		build.gradle.kts
check_darkfid.py		check_darkfid.py
crowdin.yml		crowdin.yml
gradle.properties		gradle.properties
gradlew		gradlew
gradlew.bat		gradlew.bat
lwd-testnet.toml		lwd-testnet.toml
settings.gradle.kts		settings.gradle.kts
test_sublist.kt		test_sublist.kt

Navigation Menu

Uh oh!

Repository files navigation

Nighthawk Wallet (DarkFi Edition) — Android

Contents

Download

Quick start

Repository layout

Prerequisites

Build

UniFFI native libraries

Android app

Chat (DarkIRC / EventGraph)

Architecture

UniFFI & native bridge

Privacy & security

TLS pin (remote HTTPS)

Tor (SOCKS5)

Sync & network

Data-at-rest & logging

UnifOMR (scheme 0x05)

What the server learns

Sync modes

Verification

Known issues

Install & shortcuts

Related projects

Contributing & support

Disclaimers

About

Releases

Contributors

Languages

Uh oh!

Latest commit

History

Folders and files

Repository files navigation

Nighthawk Wallet (DarkFi Edition) — Android

Contents

Download

Quick start

Repository layout

Prerequisites

Build

UniFFI native libraries

Android app

Chat (DarkIRC / EventGraph)

Architecture

UniFFI & native bridge

Privacy & security

TLS pin (remote HTTPS)

Tor (SOCKS5)

Sync & network

Data-at-rest & logging

UnifOMR (scheme 0x05)

What the server learns

Sync modes

Verification

Known issues

Install & shortcuts

Related projects

Contributing & support

Disclaimers

About

Topics

Resources

Contributing

Stars

Watchers

Forks

Releases

Contributors

Languages