Shujian AISJ-Mail
Shujian AISJ-Mail
A lightweight, AI-powered email client built local-first — encrypted data, on-premise deployment, and the classic desktop mail experience, back.
A lightweight Windows / macOS desktop and Android mobile client made for heavy email users — emails and credentials are encrypted and stored locally, and the built-in SJ-AI assistant actually does mail work: search, summarize, draft, translate, and analyze attachments, with human approval for every sensitive action.
SJ-Mail v0.8.0 real main window — the classic three-pane layout, reorganized mail area, and built-in AI reading assistant
Emails and account credentials are encrypted and stored locally — no cloud sync required. Read and search downloaded mail offline, and keep long-term local archives.
Not just chat — it searches mail, summarizes folders, drafts replies, translates content, and analyzes attachments. A daily briefing is generated every day (or hourly); since v0.6.0, contact and relationship profiles feed into AI writing context, so it knows you and your counterpart better.
Compatible with the mail systems of multiple central SOEs, state-owned enterprises, and financial institutions; the full AI solution deploys on-premise against company-owned LLMs — data never leaves. Since v0.6.0, profile analysis incorporates enterprise org-structure context, so AI understands people in a corporate setting.
Process large volumes of mail efficiently and securely — local-first — with a built-in AI assistant that dramatically improves reading, writing, and management.
Mail is downloaded to a local SQLite database; account passwords are encrypted with AES-256-GCM. Local archiving keeps mail long after it leaves the server — readable and searchable offline.
AI reads the local mail index directly and can answer "which emails about the contract came in last week?"; drafting is context-aware, and translation preserves HTML formatting. Since v0.6.0, AI writing brings in your relationship profile with the recipient — their role, your shared history — for more tactful replies, and matches your own writing style.
Compatible with the mail systems of multiple central SOEs, state-owned enterprises, and financial institutions; the full AI solution deploys on-premise against company-owned LLMs with unified signatures, filter rules, and org structure — data never leaves. Since v0.6.0, AI profiles automatically incorporate enterprise directory information (department / title) for corporate context.
The classic three-pane layout, a resident system tray with instant new-mail notifications, and independent compose windows for true multi-window work.
A modern rebuild of the classic desktop mail experience — the three-pane layout keeps the learning curve low and everything within reach.
Add multiple mailboxes (IMAP/SMTP/CAPI), each with its own folder tree, signatures, and filter rules, all syncing in the background.
Inbox, sent, drafts, and custom folders, with live unread badges wired into the notification center.
HTML is sanitized via DOMParser before rendering; preview and download attachments; reply/forward/move/archive in one click.
Quick search within the current folder, cross-folder global search (with source labels), and suggestions based on your history.
Archive mail from the server to local storage — keep the original structure, organize by year/month, or use custom directories, with a second confirmation and progress display before archiving.
Combine multiple conditions (sender, subject, attachments, etc.); actions include move, flag, delete, and forward; rule priorities are adjustable, with a built-in test run.
Driven by our self-developed SJ-AI protocol (currently v3.14) with a "server orchestration + client execution" architecture. AI accesses local mail directly and truly "operates email" inside the local security boundary.
Query mail, contacts, and schedules in natural language; continuous context-aware conversations with local history. New sessions open with a "what can I do for you" guide.
One-click reply drafting based on the original thread, with continuation, polishing, and formalization; describe what you want in Chinese to generate English / Japanese / Korean mail.
Translate whole emails while preserving HTML layout; large mails are translated chunk-by-chunk in streaming fashion, across Chinese / English / Japanese / Korean.
Extract key points, to-dos, and critical times from a single message; batch-summarize by folder, recent N messages, or date range; the daily briefing can be re-read hourly and customized by type.
Four profile types (user / enterprise / contact / relationship) produced in one analysis; enterprise contacts incorporate org-structure context; profiles feed AI writing so it understands both sides.
Tag clients and leaders as VIP contacts: their inbound mail is automatically recognized and prioritized; AI builds and refreshes relationship profiles on a schedule; before you send, AI checks spelling, attachments, and sensitive information — important mail never ships with low-level mistakes.
Hand image attachments to multimodal models (scans, invoices, screenshots, design drafts); images are read locally as data URIs.
AI may suggest, but it cannot perform high-risk actions on its own — every sensitive action requires your click to confirm, and approvals time out after 5 minutes (treated as declined), guarding against misoperation and prompt injection.
Local-first + local encryption + local approval; inheriting the security DNA of eYou's two decades serving central SOEs and governments, with user information protection as the bottom line.
Account passwords and AI keys are encrypted with AES-256-GCM into a local SQLite database, with keys backed by the OS keyring.
Email HTML is sanitized via DOMParser before rendering, blocking XSS and phishing scripts.
Sensitive actions always require user approval; tool definitions are provided by the client, and the server stores no extra schema — a smaller attack surface.
Operation logs rotate daily in the user data directory; email content is never uploaded to remote logging.
The enterprise solution lands on three points: add AI capabilities on top of your existing mail system without replacing it; compatible with multiple mail system brands; and deploy the entire AI solution inside the corporate intranet — data never leaves.
Keep your existing mail system, accounts, and historical mail; the client + AI server layer plugs in on top — employees are productive from day one
sj-ai-server deploys entirely inside the enterprise intranet, connecting to company-owned LLMs — mail data never touches the public network
Connected via eYou CAPI / IMAP, covering energy, finance, and power industries
From the morning briefing to enterprise rollouts, SJ-Mail fits every email workflow.
Open your computer at 10am — the briefing card has already summarized overnight and morning mail by section; click a key point to jump straight to the source email, and translate English mail in passing.
Saves 15–20 minutes of reading mail one by oneReceive an English price inquiry, hit "AI Write → Reply" for a professional draft, adjust pricing and delivery dates, and send after a final AI-confirmed check.
3× faster English repliesSearch all project correspondence, select, and archive locally with the original folder structure intact; free up server space while keeping a permanent local record.
Compliant, controllable, long-term archivingReceive a Japanese meeting notice — AI translates the whole email with formatting intact, summarizes time, place, and agenda, and creates a calendar event in one click.
Fewer missed details across languagesBring Gmail, corporate mail, and QQ Mail together in SJ-Mail, archive by project into local folders, and stop switching between webmail tabs.
One client for every mailboxConnect to the corporate mail service via CAPI, push signature templates centrally, auto-sync the org structure on employee login, and meet compliance with sensitive-action approvals.
Unified entry · lower maintenance costOpen a customer's contact details and the AI profile card shows their role, closeness with you, recent joint projects, and shared topics; when drafting a reply, AI already knows this context and keeps the right tone.
From "AI reads one email" to "AI understands the relationship"Tag a key client as a VIP contact — customer; an AI profile is built automatically. Before the quote goes out, the pre-send AI gate checks spelling, attachments, and sensitive information; after sending, read tracking tells you the perfect moment to follow up; their replies arrive pre-tagged and prioritized.
Zero-tolerance for send errors · precise timing · a relationship on fileLocal data sovereignty + built-in AI + enterprise CAPI — SJ-Mail stands alone on the dimensions that matter.
| Dimension | Outlook | A mainstream client | Gmail Web | Spark | SJ-Mail |
|---|---|---|---|---|---|
| Local storage | Partial | Yes | No | No | Yes |
| Offline reading | Yes | Yes | Limited | Limited | Yes |
| Multi-account | Strong | Medium | Medium | Strong | Strong |
| AI integration | Cloud | None | Cloud | Cloud | Local security boundary |
| Contact & relationship profiles | None or cloud | None | None or cloud | None or cloud | In the local security boundary, with org structure & writing context |
| VIP contacts & pre-send checks | None | None | None | None | Relationship tagging / inbound recognition / auto profiling / pre-send AI checks |
| Large-list performance | Medium | Weak | Medium | Medium | Virtual scrolling, thousands of emails smooth |
| Data sovereignty | Microsoft cloud | Local | Google cloud | Cloud | Local-first |
| Enterprise CAPI | No | No | No | No | Yes |
| Chinese experience | Medium | Strong | Medium | Medium | Strong |
| Startup speed | Slow | Fast | Browser-dependent | Fairly fast | Fast |
v0.8.0 extends AI from "reading mail" to "maintaining relationships for you": tag who's important, recognize their inbound mail automatically, keep profiles fresh on a schedule, and gate outgoing mail behind AI checks — alongside a standalone Contacts Hub, buttery-smooth scrolling over thousands of emails, four rounds of design-review polish, and the all-new second-generation brand icons.
A lightweight CRM built into the mail client: tag contacts as client / leader / colleague / family from contact details, org directory, or the reading pane; their inbound mail is auto-flagged on arrival; before you send, AI checks spelling, attachments, and sensitive information (tone judged by relationship), fail can block, offline local rules apply, and nothing silently passes.
Contact management becomes a standalone-window hub (with a scoped read-only embedded view in the main window): org directory and personal address book in account sections, three-way concurrent global search across local + org + VIP (VIP pinned on top), cross-account address-book aggregation with dedup, and group management.
Folders with thousands of emails no longer stutter: the mail list runs on virtual scrolling (a 4,351-row DOM shrinks to the viewport subset), date group headers stick to the top, j/k keyboard navigation follows across groups, and column-width dragging is rAF-throttled — scroll frame rate is decoupled from mail count.
The v0.7.x series makes email "sendable, trackable, and tidy": v0.7.1 shipped full read tracking (sj-track), v0.7.6 landed replied/forwarded flags and the unified address book; along the way, a full security hardening pass, Coremail missing-mail fixes, and a comprehensive compose-editor overhaul.
Enable tracking on compose in one click (whole-message or per-recipient granularity); the sent list shows read badges and "M of N read", a detail panel shows per-recipient open status and reading environment (region / OS / client / device), and quota usage stays transparent.
After you reply or forward, the list, preview, and reading windows show the indicator automatically and write the server flag back (IMAP \Answered / $Forwarded), consistent across devices; contacts from multiple accounts merge into one address book, deduplicated by email address.
A one-time AI guide on first launch takes new users from zero to the morning briefing, writing assistant, and reading tools via "one-click activation"; the system title bar and toolbar merge into a single row for a cleaner, borderless window.
v0.7.0 polished the AI experience around "peace of mind": lost API keys can be recovered self-service with old keys auto-revoked; the AI dialog minimizes to the tray so long tasks run in the background; the usage panel queries real server-side usage with quota policy at a glance.
API keys are stored as hashes only and can never be recovered — since v0.7.0 you no longer need an admin: if application says the account already exists, start a self-service reset in one click and a new key is issued automatically after email verification.
The AI dialog can minimize to the bottom-right tray and notify you when streaming completes — long tasks like full-email translation or batch summarization run in the background without blocking your work.
The usage panel moved from placeholder data to real server-side usage queries, showing quota reset policy; when writing / translation / summarization / profiling quotas run out, you get a clear quota message instead of a mysterious failure.
v0.6.0 pushed professional mail handling further: forward an entire original email as a .eml attachment; contact and relationship profiles enter AI writing context; app-wide font-size presets make reading more comfortable.
A split forward button packs the entire original message into a single .eml (message/rfc822) attachment, preserving the original headers, body structure, and all attachments. Ideal for handing the complete original email to a third party (lawyers / archival filings / cross-system migration).
v0.6.0 injects user, contact, and relationship profiles into AI writing, summarization, and classification — from "AI reads one email" to "AI understands the relationship".
v0.8.0 released: the Windows x86-64 desktop is fully upgraded to v0.8.0 (all-new brand + VIP contacts), with macOS dual-channel releases in step at v0.8.0; Windows ARM64 is at v0.7.6 and Android at v0.7.7; domestic-platform (Xinchuang) builds are on the way.
Beyond the all-new SJ-Mail client, we also offer AI enhancement plugins for existing mail clients — you're welcome to keep using them.
Brings AI capabilities — smart translation, work-report generation, mail-intent analysis — to the WeiMail client.
⬇ Download (468 KB)Brings AI capabilities — smart translation, work-report generation, mail-intent analysis — to the YouMail client.
⬇ Download (349 KB)We're bringing SJ-Mail's core capabilities to more platforms — stay tuned.
Coming soonLocal-first · AI-enhanced · the classic desktop mail experience, back
⬇ Download SJ-Mail for free