Live Updated weekly · backwards-compatible by default

The changelog.

We ship every week. Reply detection, warmup, billing rails, the API and the agent surface — here's everything that landed, newest first.

47
Releases in 2026
~1.3/wk
Average cadence
2.4s
Reply detection P50
0
Breaking changes shipped
June 2026
Jun 19, 2026
engine 2.11
Shipped

Reply streaming v2 — 2.4s inbound, end to end

We rebuilt inbound detection on push subscriptions instead of polling. Gmail API mailboxes ride Pub/Sub; Microsoft Graph mailboxes ride change-notification subscriptions. The moment a prospect replies, classification and the Claude draft are computed on the same hop.

  • P50 from inbound reply to a ready-to-send AI draft is now 2.4 seconds across Gmail and Graph senders.
  • SMTP/IMAP mailboxes fall back to a 30-second adaptive poll — down from 2 minutes.
  • The reply.received webhook now carries latency_ms and the draft inline, so you can auto-respond without a second round-trip.
Jun 11, 2026
warmup 3.4
ShippedImproved

Cross-customer warmup pool — tiered reputation

Every NuMail mailbox warms inside one shared, human-looking conversation network. We split that pool into reputation tiers so a brand-new domain never trades engagement with an aged, high-trust one — and inherits trust gradually as it earns it.

  • Three tiers — seedling, established, trusted — assigned from domain age, bounce rate, and reply health.
  • Mailboxes promote automatically; a wobble in placement demotes a tier and tightens volume instead of burning the domain.
  • Pool now spans 40k+ mailboxes, so warmup conversations look like real B2B threads, not a closed loop.
Jun 3, 2026
senders 1.9
Shipped

Mailbox ramp scheduling

New mailboxes now follow a daily send ramp instead of a flat cap. You set a target; NuMail walks volume up on a curve that mirrors how a real human inbox grows, and pauses the ramp on any deliverability signal.

  • Per-mailbox ramp editor: starting volume, daily increment, ceiling, and send window with timezone.
  • Ramp auto-pauses on a spam-placement or bounce spike and resumes once the mailbox recovers.
  • Exposed on the API at PUT /v1/mailboxes/:id via a ramp object.
May 2026
May 27, 2026
mcp v0.6
Beta

MCP server — public beta

NuMail now speaks the Model Context Protocol. Drop @numail/mcp into Claude Desktop, Cursor, or any agent runtime and your AI can run real outbound — create campaigns, triage the unibox, draft and approve replies — against the same API the dashboard uses.

  • 26 tools across campaigns, leads, mailboxes, unibox, and analytics, scoped to a workspace API key.
  • Read tools are open by default; write tools require an explicit allow_writes flag so an agent can't launch by accident.
  • Walkthrough and config on the MCP page →
May 19, 2026
ab 2.0
Shipped

Statistical A/B auto-promote

Subject and opener variants now resolve themselves. We run a sequential test on reply rate and promote a winner the moment it clears significance — no fixed sample size, no guessing when to call it.

  • Sequential testing means you stop as early as the data allows, without inflating false positives.
  • When a winner is declared, remaining sends shift to it automatically and the ab_winner.declared webhook fires.
  • Per-variant significance is readable any time at GET /v1/ab/variants/:id.
May 8, 2026
connect 1.5
Shipped

Stripe Connect white-label — general availability

Agency-tier white-label is out of preview. Bill your end-clients on your own Stripe, under your own brand, from sub-workspaces inside one parent dashboard. Money never touches us — we take a flat per-sub-workspace fee and step aside.

  • Custom-domain login at app.youragency.com with per-sub-workspace logo and color.
  • Stripe Checkout links auto-generated per client; daily payouts straight to your account.
  • Full story on the agencies page →
May 2, 2026
webhooks 1.4
ShippedImproved

Per-workspace HMAC webhooks

Webhooks went from one global endpoint to many, scoped per workspace and per event. Every delivery is signed with HMAC-SHA256 and a per-endpoint secret, so a sub-workspace's events can route to that client's own infrastructure.

  • Multiple endpoints per workspace, each subscribed to a subset of the 10 event types.
  • Signatures use a timestamped X-NuMail-Signature: t=…,v1=… header to block replay attacks.
  • Failed deliveries retry with exponential backoff for 24h and can be replayed by hand from the dashboard.
April 2026
Apr 21, 2026
crm 1.0
Shipped

HubSpot two-way sync

Connect HubSpot once and NuMail keeps contacts, activity, and reply status in sync both directions. Positive replies create or update the deal; a lead going quiet in HubSpot pauses their sequence here.

  • Inbound: every send, open, click, and classified reply writes back as a timeline event on the contact.
  • Outbound: HubSpot list membership and lifecycle stage can enroll or suppress leads automatically.
  • Field mapping is configurable; the sync is idempotent and survives a token refresh without dropping events.
Apr 9, 2026
senders 1.7
Shipped

Microsoft Graph senders

Outlook and Microsoft 365 mailboxes now connect over the Graph API — not SMTP. You get the same first-class send pipeline, warmup, and reply streaming we already gave Gmail API mailboxes, with proper OAuth and no app passwords.

  • Connect via Microsoft OAuth; tokens refresh silently and revocation surfaces as a mailbox.error event.
  • Graph change-notification subscriptions feed the same 2.4s reply stream as Gmail Pub/Sub.
  • Threading, In-Reply-To headers, and sent-folder placement match native Outlook behavior.
Apr 1, 2026
engine 2.6
Fixed

Reply classifier — thread-context fix

The classifier occasionally read an auto-reply that quoted the original email as a fresh positive reply. It now strips quoted history and signatures before scoring, so out-of-office and bounce-style autoresponders land in the right bucket.

  • Out-of-office and "wrong person" replies now classify correctly instead of pinging you as warm leads.
  • No action needed — the fix is server-side and re-scores nothing retroactively.
March 2026
Mar 17, 2026
unibox 2.2
ShippedImproved

Claude AI drafts — voice matching

AI drafts now learn the voice of the mailbox they reply from. We score every draft against your past sent mail and surface a voice_match number, so you can auto-approve the ones that already sound like you.

  • Drafts inherit tone, sign-off, and typical length from the sender's own history.
  • A voice_match score (0–1) ships on every draft, in-app and over the API, for confidence-gated auto-send.
  • Three length presets — short, standard, detailed — selectable per reply.

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