Your sales operation should never put business-critical email at risk.
Thawbound designs and manages isolated prospecting systems: dedicated sending domains, authenticated infrastructure, controlled volume and account research grounded in verifiable signals.
Your primary domain remains outside cold sending. Every prospecting decision starts with evidence. Replies and meeting coordination are managed within a documented operation.
Direct access to the system architect. Clear technical scope. Written reporting.
Technical assessment by email. No sales calls. Your time goes into decisions, not discovery meetings.
Your main domainstays out of cold sending.
Every accountis researched before the first email.
Every emailis written for its recipient.
Prospecting, invoices and customer support should not share a sending reputation.
When cold outreach uses your primary domain, complaints and poor sending practices can compromise the infrastructure your company relies on for contracts, billing and customer communication.
The consequences extend beyond campaign performance: delayed payments, missed customer requests and uncertainty over whether critical messages arrived.
This is an architectural exposure that better copy cannot fix.
Separate the infrastructure. Control the operation.
Thawbound builds prospecting on dedicated secondary domains and inboxes, with SPF, DKIM and DMARC authentication, pre-send warm-up, conservative sending limits and deliverability monitoring.
Account research determines whether there is a credible reason to contact a company.
Isolation reduces exposure. Monitoring informs when to adjust or stop.
Protect the domain. Study the account. Handle the replies.
Founded by Paulina Castillo, Thawbound developed its own “Metodología de Aislamiento de Dominios para Prospección”: a process that separates B2B cold email from a company’s main domain using secondary domains, dedicated inboxes, SPF, DKIM, DMARC, pre-send warm-up and deliverability monitoring.
- 01
Isolated infrastructure
Secondary domains and inboxes, authenticated with SPF, DKIM and DMARC, and warmed for 2 to 3 weeks before the first send.
- 02
Study first
Before an email goes out, we look into the company: what it sells, who it serves, what changed recently. The email is written for that company, not adapted from a template. No reason to write, no email.
- 03
Managed operation
Sequences, replies and meeting booking handled by us. You get a weekly report by email.
What we look at before the first email.
Illustrative example. The agency, the prospect and every detail are invented to show the format.
Research notes on the prospect
- 1Ledgerline, accounting software for small firms, about 40 people.
- 2Launched a payroll module in September.
- 3The new payroll pages do not appear yet in searches for payroll software for small firms.
- 4Currently hiring a content marketer.
Subject: Ledgerline payroll pages
Hi Sam,
Saw the payroll module went live in September.2 The new pages do not show up yet when small firms search for payroll software,3 which is where most of your current customers would look.
You are also hiring a content marketer,4 so this may already be on the list. If useful, I can send the three page fixes we would make first.
Alex
Built to protect your domain and your market.
- 01
Verified addresses only
Contacts are validated before sending. Catch-all and risky addresses are left out.
- 02
Conservative volume
A low daily cap per inbox, spread across the sending domains.
- 03
Authentication from day one
SPF, DKIM and DMARC configured before any warm-up starts.
- 04
Facts only
Every line in an email traces back to something we found about the account. If we cannot verify it, we do not write it.
- 05
Clear opt-out
Every email includes one, and removals are honored.
Setup plus retainer, scoped to your volume.
Engagements start with a one-time setup and a monthly retainer, scoped to your volume and markets.
From $1,200/month
Plus a one-time setup, scoped with the audit.
A full-time SDR in the US typically costs more than $5,000 a month before tools.
Setup covers
- Secondary domains and inboxes
- DNS authentication
- Warm-up
- Targeting and message approach
- Weekly report format
Retainer covers
- Account research
- Emails written for each account
- Reply handling and meeting booking
- Deliverability monitoring
- Weekly report
Direct access to the architect of your prospecting system.
Thawbound is a boutique technical consultancy specializing in isolated B2B prospecting infrastructure.
I lead the architecture and operational approach for each engagement. You work directly with the person responsible for the system’s design, sending controls and technical decisions.
Our process is asynchronous by design. Assessments, implementation scope and reporting are delivered in writing, giving your team a clear record of decisions without another recurring meeting.
Send your domain and target market. Within two business days, I will outline your current exposure, the proposed architecture and the scope of implementation.
No sales calls. A technical assessment you can evaluate on its merits.
Paulina CastilloFounder & Systems Architect, ThawboundLinkedIn profile
Direct answers.
Will this affect my company domain?
No. All cold sending runs on secondary domains set up for that purpose. Your main domain is not used.
Is this a mass mailing?
No. Volume is deliberately low. We study each company first and write each email for it, using facts we can verify.
How long until the first emails go out?
Domains and inboxes are warmed for 2 to 3 weeks first. We use that time to agree on targeting and messaging with you.
How do interested replies reach us?
We reply to interested prospects and book the meeting directly on your calendar, with a short summary for your team.
Do we need to get on a call?
No. Audit, proposal and terms are handled by email. When a walkthrough helps, we send a recorded video.
What does it cost?
From $1,200 a month, plus a one-time setup scoped with the audit. The retainer depends on volume and markets. You get the exact terms by email after the audit.
Request an audit of your domain.
Tell us your domain and who you sell to. You get a review of your current email setup and a short plan for isolating outbound. By email, no call.
- Reply by email within 2 business days
- Prepared by Paulina Castillo, Founder
- Prefer email? contact@thawbound.com
Request received.
You will get your audit from Paulina Castillo by email within 2 business days. No call needed.