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Gemini Nexus

Desktop gateway that pools Google accounts behind a local OpenAI/Anthropic-compatible API, with encrypted credentials and auto-switching.

Quickstart · Architecture · Security · Issues ![Stack](https://img.shields.io/badge/Stack-Electron_41_%C2%B7_React_19-47848F?logo=electron&logoColor=white) ![Status](https://img.shields.io/badge/status-v0.15.3_active-brightgreen) ![License](https://img.shields.io/badge/license-CC_BY--NC--SA_4.0_%2B_MIT-lightgrey) English · Português · 中文 · Español
## 📌 The problem Working with AI-powered IDEs and coding tools on a single Google account means quota that runs out, manual account switching, no idea how many tokens you spent, and no view of what the proxy actually sends upstream. Gemini Nexus keeps all accounts in one pool, switches between them automatically and shows the traffic. ## ✨ What it does - **Pools** Google accounts added through OAuth, with status (Active, Rate Limited, Expired), last-used time and an optional per-account proxy URL. - **Switches** accounts automatically when quota drops below 5 % or an account is rate-limited; `CloudMonitorService` polls quota every 5 minutes. - **Schedules** requests across the pool in `cache-first`, `balance` (default) or `performance-first` mode, with a per-account circuit breaker (default backoff 60 s → 5 min → 30 min → 2 h). - **Serves** `POST /v1/chat/completions` (OpenAI), `POST /v1/messages` (Anthropic), `GET /v1/models` and `GET /v1/models/capabilities`, so Cursor, Windsurf, OpenCode, Claude Code and similar clients can connect. - **Maps** requested model names to upstream models through the `custom_mapping` and `anthropic_mapping` settings; request timeout defaults to 120 s. - **Tracks** token usage per account and model, charts prompt and completion tokens, and estimates cost with editable per-model pricing. - **Inspects** traffic (latency, status, model), replays logged requests and generates cURL and Python snippets plus an IDE Quick Setup. - **Protects** stored credentials with AES-256-GCM and an OS-keychain master key (see [Security model](#-security-model)). ## 🖼️ Demo
Screenshots

Main dashboard

Usage analytics

Proxy monitor

Routing config

Documentation

Active connections

Settings

## 🚀 Quickstart **Use a release.** Download the build for your platform from [Releases](https://git.evandro.dev.br/evandro/gemini-nexus/releases), open the app, add at least one account, enable the proxy (it is disabled by default) and point your IDE at it: ```text API Base URL: http://localhost:8045/v1 (default, configurable on the Proxy page; development builds use 8046) API Key: (copy it from the Proxy page in the app) Model: gemini-3-flash (or any mapped model) ``` > [!WARNING] > Builds are not code-signed. If Windows shows "Windows protected your PC", click **More info → Run anyway**. **Build from source.** | Tool | Minimum version | |---|---| | Node.js | 20+ (recommended in `AGENTS.md`; `.nvmrc` pins 22.17.1) | | pnpm | 10.11.0 (`packageManager`; lockfile is `pnpm-lock.yaml`) | | Native toolchain | needed by `better-sqlite3` and `keytar`: Visual Studio 2022 Build Tools (C++) on Windows, Xcode Command Line Tools on macOS, `build-essential` + `python3` + `libsecret-1-dev` on Ubuntu (`base-devel` + `python` + `libsecret` on Arch) | ```bash git clone https://git.evandro.dev.br/evandro/gemini-nexus.git cd gemini-nexus pnpm install # postinstall runs scripts/setup-dev.js --check-only to verify the toolchain pnpm start # dev mode (Electron + Vite HMR) pnpm run make # installers/packages for the current platform pnpm run make:win # Windows: extracts WiX from wix314-binaries.zip, then runs make ``` There is no `.env.example` and no variable is required. Optional variables read by the code or described in the docs: | Variable | Required | Description | |---|---|---| | `HTTP_PROXY` / `HTTPS_PROXY` / `NO_PROXY` | No | Route the app's outbound requests through a local proxy (see [TLS inspection](#-security-model)). | | `NODE_EXTRA_CA_CERTS` | No | Extra CA certificate for Node-side TLS when inspecting traffic. | | `SENTRY_DSN` | No | Sentry DSN used when error reporting is enabled. | ## 🧱 Architecture ```mermaid flowchart LR C["Client: Cursor, Windsurf, OpenCode, Claude Code"] -->|"/v1/chat/completions, /v1/messages"| P["NestJS proxy, port 8045"] P --> S["Account scheduler and circuit breaker"] S -->|"Google OAuth account"| G["Google upstream APIs"] M["CloudMonitor and AutoSwitch, quota every 5 min"] -->|"quota polling"| G S -->|"reads accounts"| DB[("SQLite: better-sqlite3 and Drizzle")] M --> DB K["AES-256-GCM, master key in OS keychain"] -->|"encrypts tokens"| DB ``` 1. A client sends OpenAI- or Anthropic-format requests to the NestJS proxy (Fastify, bound to `0.0.0.0`). 2. The proxy guard checks the API key when one is configured; with an empty key the proxy runs in open mode. 3. The token manager picks an account according to the scheduling mode and each account's circuit-breaker state, then calls Google's upstream APIs with that account's OAuth token. 4. `CloudMonitorService` polls quota every 5 minutes and `AutoSwitchService` switches the active account when quota is below 5 % or the account is rate-limited. 5. The React 19 renderer (TanStack Router and Query) talks to the main process over oRPC on IPC; accounts, usage and settings live in SQLite (better-sqlite3 + Drizzle). Design notes: [`docs/cloud_features.md`](docs/cloud_features.md). ## 🔒 Security model Gemini Nexus holds OAuth tokens for several accounts and forwards traffic upstream, so credential handling is the core of the design. Everything below is implemented in this repository; limits are stated where they exist. - **Credential storage and isolation.** `token_json` and `quota_json` are encrypted with AES-256-GCM (unique IV per operation, authenticated) before they reach SQLite. The master key lives in the OS credential store through `keytar` (Windows Credential Manager, macOS Keychain, Linux Secret Service/libsecret), never in a plain file. Legacy plaintext rows are migrated at startup. Accounts are kept in their own database (`cloud_accounts.db`), independent from the IDE's local database. - **Log masking.** Keys such as `token`, `refresh_token`, `api_key`, `authorization`, `cookie` and `client_secret` are replaced by `[REDACTED]` before logging ([`src/utils/sensitiveDataMasking.ts`](src/utils/sensitiveDataMasking.ts)); the traffic logger also redacts the `authorization`, `x-api-key` and `cookie` headers. - **Request logging, not an audit trail.** Winston writes API, traffic and app logs to rotating files (API log: 30 days, 50 MB per file). These are operational logs, not a tamper-evident audit trail; the `*-audit.json` files are rotation bookkeeping from `winston-daily-rotate-file`. - **Proxy access.** The proxy is off by default. Once enabled it listens on `0.0.0.0`, and requests are authenticated only when `api_key` is non-empty (empty means open mode). Set a key and keep it private. - **TLS inspection (debugging only).** [`docs/proxyman-install.md`](docs/proxyman-install.md) and [`docs/proxyman-debugging.md`](docs/proxyman-debugging.md) explain how to read the app's HTTPS traffic with Proxyman: trust its root CA, set the proxy variables and `NODE_EXTRA_CA_CERTS`, then start the app. `NODE_TLS_REJECT_UNAUTHORIZED=0` (and the script's `-AllowInsecureTls` flag) is a temporary override; never leave it on. Do not commit proxy addresses, certificate paths, cookies or OAuth codes, and redact logs before sharing them. `scripts/start-antigravity-with-proxyman.ps1` targets the installed official Antigravity client, not this app. - **Error reporting.** Sentry reports (they need `SENTRY_DSN`) are gated by the `error_reporting_enabled` setting, which `DEFAULT_APP_CONFIG` ships as `true`; turn it off in Settings to opt out. The Windows user-name segment is masked in reported exception messages. Supported versions and how to report a vulnerability: [`SECURITY.md`](SECURITY.md). ## 🗂️ Structure ```text src/ ├── components/ # UI (proxy/, usage/, ui/ primitives) ├── ipc/ # oRPC routers (account, cloud, config, gateway, usage...) ├── server/ # NestJS proxy gateway (modules: proxy, usage) ├── services/ # AutoSwitchService, CloudMonitorService, GoogleAPIService ├── routes/ # index, usage, proxy, settings ├── utils/ # paths, logger, sensitiveDataMasking └── tests/ # unit tests (Vitest) and E2E (Playwright) cli/ # separate Python CLI for account switching and quota checks docs/ # design notes and Proxyman guides scripts/ # setup-dev, build-windows, generate-assets ``` ## 🧪 Scripts | Command | What it does | |---|---| | `pnpm start` | Run the app in dev mode (`electron-forge start`, with `DEBUG=electron-forge:*`). | | `pnpm run dev` | Same as `start`. | | `pnpm run package` | Package the app with Electron Forge, without building installers. | | `pnpm run make` | Build installers/packages for the current platform. | | `pnpm run make:win` | Windows build helper: extracts WiX from `wix314-binaries.zip`, adds it to `PATH`, runs `electron-forge make`. | | `pnpm run publish` | Publish through Electron Forge. | | `pnpm run setup` | Run `scripts/setup-dev.js`: detect the native toolchain and install or guide the setup. | | `pnpm run postinstall` | `scripts/setup-dev.js --check-only`; runs automatically after `pnpm install`. | | `pnpm run lint` | ESLint over the repo. | | `pnpm run format` | Prettier check. | | `pnpm run format:write` | Prettier write. | | `pnpm test` | Vitest unit tests (`vitest run`). | | `pnpm run test:watch` | Vitest in watch mode. | | `pnpm run test:unit` | Vitest (default mode). | | `pnpm run test:e2e` | Playwright E2E tests. | | `pnpm run test:all` | Unit tests, then Playwright. | | `pnpm run type-check` | `tsc --noEmit`. | ## 📚 Documentation - [`docs/cloud_features.md`](docs/cloud_features.md): account pool, quota monitoring and auto-switch design. - [`docs/proxyman-install.md`](docs/proxyman-install.md) and [`docs/proxyman-debugging.md`](docs/proxyman-debugging.md): TLS inspection setup (Windows). - [`docs/OpencodeAPI.md`](docs/OpencodeAPI.md): OpenCode custom-endpoint integration (in Portuguese). - [`cli/README.md`](cli/README.md): the Python command-line tool. - [`CONTRIBUTING.md`](CONTRIBUTING.md), [`SECURITY.md`](SECURITY.md), [`CODE_OF_CONDUCT.md`](CODE_OF_CONDUCT.md), [`CHANGELOG.md`](CHANGELOG.md), [`LICENSE`](LICENSE), [`LICENSE-MIT`](LICENSE-MIT). - Translations: [Português](README.pt-BR.md), [中文](README.zh-CN.md), [Español](README.es.md). ## 🛣️ Limitations and next steps - Upstream access goes through Google's `v1internal` Cloud Code endpoints and OAuth scopes ([`src/services/GoogleAPIService.ts`](src/services/GoogleAPIService.ts)). These are internal, undocumented APIs and may change without notice. The project is unofficial and not affiliated with Google or Anthropic. - Accounts are added through Google OAuth; Claude models are reached through model mapping, not through separate Claude accounts. - End-to-end tests are not run in CI (Electron needs a graphical environment); run `pnpm run test:e2e` locally. - The Windows MSI is only produced when the WiX Toolset is available on the build machine; otherwise the Windows artifact is the ZIP. - The workflows in `.github/workflows/` are written for GitHub (they call the `gh` CLI and the GitHub release publisher), so this README shows no CI badge. - Next step stated by the project: migrate the remaining original code to MIT (see [License](#-license)). ## 🤝 Contributing Read [`CONTRIBUTING.md`](CONTRIBUTING.md) and [`CODE_OF_CONDUCT.md`](CODE_OF_CONDUCT.md). Releases are versioned by semantic-release from Conventional Commits. Before opening a PR, these must pass: ```bash pnpm run lint && pnpm run format:write && pnpm run type-check && pnpm test ``` ## 📄 License Mixed licensing: code inherited from [AntigravityManager](https://github.com/Draculabo/AntigravityManager) (by Draculabo) is [CC BY-NC-SA 4.0](LICENSE) (non-commercial, share-alike); all new code is [MIT](LICENSE-MIT). The project is migrating to MIT as the remaining original code is rewritten, so check both files before any commercial use.