Open-source tools — Email

21 match your filters — 20 of them answered our check today.

Watching this group for 20 days · how we check

This week8 new arrivals

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Developers5Marketers1

Skim

Live

Free, open-source, minimal, local-first email client for Windows with a native Rust core and optional bring-your-own-key AI drafting.

FreeWorks offlineOpen sourceNo tracking
What to know▼
How it works
native Rust/Tauri core, ~5MB installer, instant full-text search
What's different
minimal by design, zero telemetry, bring your own AI key
Pricing
free (MIT)
Best for
Windows users wanting a fast local email client

Watched for 6 days · last checked today

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ClawLite

Live

A personal AI assistant that runs fully on your own machine via local models, chatting through Telegram with Gmail/Calendar access.

Open sourceNo subscription
What to know▼
How it works
local models handle chat, memory and web search; cloud used only as a fallback
What's different
requires human approval for actions and runs in a Docker sandbox
Pricing
no subscription, open source (Apache 2.0)
Best for
Windows users wanting a private, local AI assistant

Watched for 5 days · last checked today

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FreeCustom.Email

Live

Instant, no-signup temporary email aliases with rotating domains to dodge blacklists, plus a public API for developers who want to build it into their own workflows.

FreeNo sign-upData stays with youOpen source
What to know▼
How it works
Creates custom, instant temporary email aliases (any inbox name) without sign-up, receiving emails in real-time from multiple rotating domains to avoid blacklists; also offers a public API and open-source frontend.
What's different
Rotating domains to avoid blacklists, plus no popups, timers, or tracking, unlike traditional temp mail tools.
Pricing
Free.
Best for
People needing disposable email for sign-up verifications or testing, and developers who want to build disposable email into their own workflows via the API.

Watched for 14 days · last checked 8d ago

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Google Maps Agent Skills

Live

Set of open-source skills that let Claude Code or other AI agents scrape Google Maps business listings, extract emails and draft cold outreach.

FreeOpen source
What to know▼
How it works
8 installable skills covering scraping, email extraction, competitor and review analysis
Pricing
3 skills free/local; scraping skills use a paid API with free starting credits
Best for
Developers building automated local-business lead-generation workflows

Watched for 6 days · last checked today

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smtp-probe

Live

An open-source CLI that checks SPF/DKIM/DMARC/MX records, verifies addresses via SMTP, and flags disposable/role-based emails, for developers validating deliverability before sending.

Open source
What to know▼
How it works
DNS health scoring, SMTP RCPT TO verification, domain typo correction, 29 RBL blacklist scans, ~74k disposable domain detection; includes REST API.
Pricing
Free demo available.

Watched for 2 days · last checked 1d ago

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InboxTap

Live

Local SMTP test server for developers to safely test signup, password reset, and OTP emails without sending anything to real inboxes.

FreeOpen source
What to know▼
How it works
Runs locally, app points to it, each test run gets an isolated inbox so parallel tests don't collide.
What's different
Open-source and free, no external delivery.
Pricing
Free
Best for
Developers testing email flows with Playwright, Vitest, Jest, or Node.

Watched for 5 days · last checked today

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OpoAlerta

Live

Lets Spanish public-sector job seekers get alerted to new postings instead of checking 18 separate regional bulletins manually.

FreeOpen source
What to know▼
How it works
Unifies BOE and all 17 regional bulletins into one search with email and Telegram alerts.
Pricing
free, open-source

Watched for 1 day · last checked today

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Warmbly

Live

Open-source cold-outreach platform with AI automation, email warmup, and real-time team collaboration for sales prospecting.

Domain registered 13 months ago

Open source
What to know▼
How it works
An open-source platform for cold outreach with AI automations, real-time collaboration, agents, and email warmup.
Best for
Sales teams doing cold email prospecting who want an open-source alternative.

Watched for 11 days · last checked 5d ago

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GemType

Live

Checks grammar and rewrites text right inside Gmail, LinkedIn, X and Reddit, using a Gemini API key you provide yourself, free and open source, no subscription.

FreeNo sign-upOpen sourceNo subscription
What to know▼
How it works
Checks grammar and rewrites text inline on any website — Gmail, LinkedIn, X, Reddit — using your own free Google Gemini API key.
What's different
Free and open source, and runs on a Gemini key you supply yourself instead of a paid subscription.
Pricing
Free, no account or subscription.
Best for
People who want a Grammarly-style writing checker without paying for a subscription or handing over data to a third-party service.

Watched for 13 days · last checked 7d ago

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Pulse

Live

An open-source AI revenue-ops copilot for sales and RevOps teams that turns pasted meeting notes into HubSpot updates, drafts follow-up emails, syncs Google Calendar context, and posts summaries to Slack, without writing to CRM or sending anything without approval.

No sign-upOpen source
What to know▼
How it works
Maps meeting notes to your HubSpot schema (deal stage, amount, custom properties, next steps) and drafts Gmail follow-ups.
Pricing
Browser demo needs no signup; source is open and self-hostable.
Best for
Sales and RevOps teams on HubSpot who want notes turned into CRM updates automatically.
Watch out
Nothing writes to CRM or sends without your approval, per the product's own description.

Watched for 7 days · last checked 5d ago

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sendthen

Live

Self-hosted, open-source email infrastructure for sending transactional email and campaigns from your own server with a developer API, instead of relying on a third-party email service.

Open sourceSelf-hosted
What to know▼
How it works
Sends transactional email, campaigns, and inbound mail from a self-hosted control plane, storing data in a single SQLite file and supporting SES, SMTP, direct MX, or a local sandbox.
Best for
Developers who want to run and own their email infrastructure rather than outsourcing it.

Watched for 7 days · last checked 6d ago

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ServiceBeard

Live

Syncs a support mailbox into GitHub, GitLab or Linear so you can run a service desk from your existing issue tracker instead of paying for separate helpdesk software.

Open source
What to know▼
How it works
Syncs a support mailbox to your issue tracker over standard IMAP/SMTP, turning incoming emails into tracked issues so you can run a service desk from GitHub, GitLab, or Linear.
What's different
Open-source and works with the automation pipelines you've already built in your issue tracker, instead of adding a separate per-seat helpdesk tool.
Best for
Teams already living in GitHub, GitLab, or Linear who want to handle customer email without buying dedicated helpdesk software.

Watched for 15 days · last checked today

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Comail

Live

A desktop email client that syncs your mailbox into local SQLite and searches it by meaning without cloud calls. Free, open source, no account or telemetry, for Gmail, Outlook or any IMAP inbox.

FreeNo sign-upOpen sourceNo tracking
What to know▼
How it works
Syncs your whole mailbox into a local SQLite database and lets you search it by meaning without any cloud calls, with keyboard-speed triage. Supports Gmail, Outlook, and any IMAP account, plus a CalDAV calendar.
What's different
Open source with no account and no telemetry.
Pricing
Free.
Best for
People who want a fast, keyboard-driven email client that keeps their mailbox local.

Watched for 13 days · last checked 7d ago

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Impri

Live

An open-source approval inbox that pauses AI agent actions until a human approves, edits or rejects them via Slack, Discord, Telegram or the web - self-hostable for teams running agents.

Domain registered 17 days ago

Open sourceSelf-hosted
What to know▼
How it works
An approval inbox that pauses AI agent actions, such as sending an email, posting a comment, or running a command, until a human approves, edits or rejects them via Slack, Discord, Telegram, mobile or web.
What's different
The approval gate is a data dependency the agent can't skip, not just a prompt instruction.
Pricing
Open source (MIT), self-hostable.
Best for
Teams running AI agents who want a human-in-the-loop approval step before actions execute.

Watched for 14 days · last checked 8d ago

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HAI 1.0 The 1.2GB AI that outcodes GPT5

Live

A 1.2GB AI model that runs fully offline on your laptop and claims to beat GPT-5 on coding benchmarks. Open source with no subscription, built for developers wanting a local coding assistant.

Works offlineOpen sourceNo subscription
What to know▼
How it works
A 1.2GB AI model that runs fully offline on a laptop, using a neuro-symbolic architecture combining neural pattern recognition with symbolic logic for software engineering tasks.
Pricing
Open-source, no subscription.
Best for
Developers wanting a local, offline coding assistant without cloud dependence.
Watch out
The listing claims it beats GPT-5 on coding benchmarks and cites a 68.4% SWE-bench Lite score — an unverified vendor claim.

Watched for 18 days · last checked 2d ago

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Moniple

Live

Kubernetes monitoring with a mobile-first dashboard and an AI assistant that reads pod/node/log data and proposes kubectl fixes you approve — for DevOps teams tired of juggling multiple dashboards and alert channels.

FreeOpen source
What to know▼
How it works
Puts every Kubernetes cluster in one mobile-first dashboard (web, iOS, Android), with an AI Doctor that scans pods, nodes, events and logs, explains the root cause in your language, and proposes fixes with the exact kubectl equivalent.
What's different
Nothing runs until you approve; open-source agent, bring your own LLM or use Moniple AI.
Pricing
Free tier included.
Best for
DevOps engineers tired of juggling multiple dashboards and alert channels.

Watched for 13 days · last checked 10d ago

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OpenMime

Live

A free, open-source native macOS Gmail client built in Swift, pitched as a no-cost alternative to the $50/year Gmail client many people recommend.

FreeOpen source
What to know▼
How it works
A native Gmail client for macOS built in Swift.
What's different
Free and open-source, positioned as an alternative to a commonly recommended $50/year native Gmail client.
Pricing
Free (compared to a $50/year paid alternative).
Best for
Mac users who want a native Gmail app without paying an annual subscription.

Watched for 15 days · last checked 2d ago

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ICTDesk

Live

An open-source live chat platform with an AI chatbot that auto-answers common visitor questions and a shared team inbox, aimed at customer support teams wanting to cut repetitive workload.

Open source
What to know▼
How it works
An open-source live chat platform where an AI chatbot crawls your website to build a knowledge base and auto-answers common visitor questions, backed by WebSocket-powered real-time chat, a shared team inbox, and real-time visitor intelligence (device, browser, location, page and conversation history).
What's different
Open source and self-hostable, combining AI auto-replies with full visitor intelligence in one tool rather than separate live-chat and analytics products.
Best for
Customer support teams who want to cut repetitive question volume with an AI chatbot while keeping a shared inbox for complex cases.

Watched for 18 days · last checked 11d ago

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Warpdrive

Live

An open-source, self-hosted alternative to Pipedrive with pipeline management, contacts, and two-way Gmail sync.

Domain registered 10 days ago

Open sourceSelf-hosted
What to know▼
How it works
An open-source, self-hosted CRM with pipeline management, a deal workspace, contacts, and two-way Gmail sync, running entirely on your own infrastructure.
What's different
Positioned as a Pipedrive alternative.
Pricing
Open-source, self-hosted.

Watched for 8 days · last checked 6d ago

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Knocket

Live

A connections app centered on reaching someone with a single 'knock,' per its tagline 'One Knock. Every Connection' — the listing does not specify the mechanism beyond that.

FreeOpen sourceNo ads

Watched for 18 days · last checked today

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Emareach AI

Email marketing isn’t dead. The way you’re doing it is.

Open sourceSelf-hosted

First seen today

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