ChatGPT answers, unedited

For your requirements, I’d shortlist Migadu, Fastmail, and MXroute, with Migadu as the strongest fit if self-service provisioning/API access matters most.

1. Migadu — my pick

Migadu is unusually well suited to a developer who wants to treat email infrastructure almost like another service.

Its API exposes domains, mailboxes, identities, forwarding, aliases, and rewrites, including create/update/delete operations. It can also return the DNS records required for a domain—including DKIM, DMARC, SPF and MX—and has a domain diagnostics endpoint. migadu.com

Crucially, you can keep DNS at your own provider rather than handing nameservers to Migadu. Their API explicitly supports creating domains with external DNS. migadu.com

That makes something like this quite practical:

Terraform/CLI → Migadu API → domain/mailbox/alias provisioning

while:

Cloudflare/Route 53/etc. → authoritative DNS → MX/SPF/DKIM/DMARC

Migadu also supports unlimited addresses and multiple domains under its paid plans, which is attractive if you're running several projects. migadu.com

Downside: the API is still described as being in early beta, so I wouldn't choose it if you need a rock-solid enterprise provisioning API. migadu.com

2. Fastmail — best polished option

Fastmail is probably the better choice if you are the primary mailbox user and don't need to automate dozens of accounts.

You can keep DNS elsewhere and manually publish the required records; Fastmail supports DKIM and lets you customize DNS records. www.fastmail.help It also has a good developer API based around JMAP and supports IMAP/SMTP. www.fastmail.com

Its admin interface also lets an account administrator add, remove, and update users and manage domains and aliases. www.fastmail.help

But: its API isn't nearly as compelling as Migadu's for mail infrastructure provisioning. Fastmail's strength is a polished mail product rather than acting like an email-hosting control plane.

3. MXroute — worth considering

MXroute is another strong option if your priority is inexpensive hosting for lots of domains/mailboxes rather than the slickest end-user experience.

I'd put it behind Migadu for your particular requirements because API-driven provisioning and developer ergonomics sound like unusually important criteria for you.

My recommendation

If I were building this as a solo developer:

Migadu + Cloudflare DNS

I'd keep authoritative DNS completely under my control and automate:

• domain creation
• mailbox creation
• aliases
• forwarding
• DKIM record retrieval
• SPF
• DMARC
• DNS verification/diagnostics

Migadu's API is particularly compelling because it exposes both the mail objects and the DNS configuration/diagnostics needed to turn a new domain into a working mail domain. migadu.com

If you tell me roughly how many domains/mailboxes you expect (e.g. 1 domain/5 addresses vs. 20 domains/100 addresses), I can narrow this down further and compare pricing, API capabilities, catch-all behavior, outbound limits, and portability.

For a tech-savvy solo developer, I’d prioritize providers that let you keep DNS at your preferred registrar/DNS host, expose proper DKIM/DMARC configuration, and don’t force you into a productivity suite.

My picks

1. migadu.com — best match for your requirements

This is probably my #1 recommendation for you.

Migadu is unusually developer-friendly: its API can create/manage domains, mailboxes, aliases, identities and forwarding rules. It can also return the exact DNS records required for a domain—including DKIM, SPF and DMARC—and provides a DNS diagnostics endpoint before activation. Migadu Migadu

The particularly nice part is that you can tell the API to use external DNS, rather than having Migadu manage your DNS. Migadu

That makes a workflow like this practical:

terraform/domain creation → Migadu API → DNS provider API → DNS verification → mailbox/alias provisioning

Choose Migadu if: you want to script everything and potentially have several domains/addresses.

2. fastmail.com — best overall email experience

I'd choose Fastmail if your priority is excellent email rather than infrastructure automation.

You can keep DNS elsewhere and simply publish Fastmail's MX, SPF, DKIM and DMARC records yourself. Fastmail explicitly supports this configuration. Fastmail Fastmail

Its DNS setup is also unusually flexible if you do let Fastmail host DNS: it supports arbitrary record types and doesn't impose the sort of restrictive DNS controls you sometimes see in bundled email services. Fastmail Fastmail

One caveat for your use case: Migadu wins decisively on API-driven provisioning.

3. purelymail.com — minimalist/cheap option

Worth considering if you mostly want basic custom-domain email without paying for a bunch of collaboration software.

I'd put it behind Migadu and Fastmail for a developer building an automated provisioning workflow, though.

4. Self-hosted mailcow — maximum control

If by "full control" you literally mean I want the mail server to be mine, mailcow is the interesting option.

You control the VPS, SMTP/IMAP stack, DKIM keys, DNS, retention, filtering, backups, etc. The tradeoff is substantial operational responsibility: reputation, IP reputation, spam handling, TLS, backups, monitoring, upgrades and deliverability become your problems.

For a solo developer, I'd only choose this if running mail infrastructure itself sounds fun.

What I'd actually use

Migadu + Cloudflare DNS (or another DNS provider with a good API).

Keep the authoritative DNS completely separate from the mail provider:

• Registrar → your registrar
• Authoritative DNS → Cloudflare/another DNS provider
• Email hosting → Migadu
• DKIM → CNAMEs published in your DNS
• SPF → TXT
• DMARC → TXT
• Provisioning → Migadu API + DNS API
• Your infrastructure → Terraform/scripts

That gives you a clean separation of concerns and makes moving away from Migadu relatively painless.

If you don't need automated provisioning: pick Fastmail instead. It's the better "set it up once and forget about it" choice, while Migadu is the better "email is another service I want to automate" choice.

For a tech-savvy solo developer, I’d optimize for DNS independence + standards access + easy provisioning, rather than a productivity suite.

My shortlist

1. Fastmail — my default recommendation

Fastmail is probably the nicest balance for a solo developer.

You can keep your authoritative DNS wherever you want and simply publish Fastmail's MX/SPF/DKIM/DMARC records. Fastmail explicitly supports an MX-only configuration, so it doesn't require handing your nameservers over to them. www.fastmail.help

Its DNS documentation exposes the actual records rather than hiding everything behind an opaque wizard, including three DKIM CNAMEs and a DMARC TXT record. www.fastmail.helpwww.fastmail.help

Why I'd choose it: excellent deliverability, polished clients, IMAP/SMTP/JMAP, aliases, custom domains, and very little operational hassle.

Downside: if your priority is programmatically creating domains/mailboxes as infrastructure, Fastmail isn't the standout.

Fastmail custom-domain documentation

2. Migadu — best if you're going to automate everything

Migadu is the interesting choice for a developer who thinks of email accounts as infrastructure.

Its API directly supports management of domains hosted by your organization, authenticated with an API key. www.migadu.com

That makes it particularly attractive if you want something like:

Terraform/script → create domain → provision mailbox/aliases → configure DNS → done

It also has a pricing model aimed at multiple domains/mailboxes rather than charging you separately for every address.

My pick over Fastmail if: you're likely to own several domains, create/delete addresses programmatically, or want email to behave more like an infrastructure service.

Migadu API documentation

3. Purelymail — ridiculously good value

Purelymail is worth a serious look if you don't care about fancy UX.

It supports your own domains, multiple users/domains without additional per-user charges, IMAP/POP3/SMTP, routing rules and Sieve filtering. purelymail.com

It's particularly appealing for a developer who wants "give me standards-compliant email and get out of my way."

Downside: less polished ecosystem and tooling than Fastmail, and I'd choose Migadu first if sophisticated provisioning automation is central.

4. Self-hosting — only if you actually want the job

Stalwart or Mailcow can give you essentially complete control over the mail stack, including DNS, DKIM signing, DMARC policy, users, routing and automation. But the hard part isn't running SMTP; it's reputation, spam handling, reverse DNS, IP reputation, backups and maintaining reliable delivery to Gmail/Outlook/Yahoo. www.itechguides.com

For a domain you actually depend on, I'd pay someone else $1–10/month rather than turn email administration into a second hobby.

What I'd choose

One domain, one developer, normal personal/business email → Fastmail.

Several domains + programmatic mailbox provisioning → Migadu.

Cheapest possible standards-based hosting → Purelymail.

"I want to own every layer and don't mind operating mail infrastructure" → Stalwart/Mailcow.

One architectural point: don't let the mail host become your DNS host unless you have a reason to. Keep DNS at Cloudflare, Route 53, your registrar, etc., and delegate only the mail records. That gives you clean separation between your web/infrastructure DNS and your email provider, and makes migration much easier. Fastmail explicitly supports this model. www.fastmail.helpwww.fastmail.help

For your stated requirements, Migadu is the one I'd investigate first if “self-service provisioning” means actual API-driven provisioning; Fastmail if it means a great admin UI with minimal operational fuss.

For a tech-savvy solo developer who wants full DNS control, DKIM/DMARC, and self-service provisioning, I would avoid traditional “domain email bundled with hosting” providers and pick something that treats email infrastructure as a first-class service.

My shortlist:

thesoftwarescout.com

My ranking for your specific requirements

1. Fastmail — probably the default choice

I would pick this for most solo developers.

Good fit because:

• Bring-your-own-domain DNS
• You control MX, SPF, DKIM, DMARC records
• Great alias support (github@, aws@, billing@, etc.)
• Works with normal clients via IMAP/SMTP
• Supports JMAP for modern integrations
• Very little operational overhead

It feels like “Unix philosophy for email”: standards-based, fast, minimal ceremony. thesoftwarescout.com

2. Migadu — if you own many domains

If you have:

• firstname.dev
• sideproject1.com
• startup2.io
• lots of catch-alls and aliases

Migadu is attractive because it is designed around domains and addresses rather than charging you per mailbox. thesoftwarescout.com

3. Zoho Mail — if cost matters

A good pragmatic choice:

• custom domains
• admin console
• DKIM/SPF/DMARC tooling
• inexpensive paid tiers

I would choose it over cheap cPanel email because deliverability and administration matter more than saving a dollar.

4. Google Workspace — if email is mission critical

If this is your professional identity and you already live in Gmail/Calendar/Docs, it is hard to beat.

The downside: you are paying mostly for the ecosystem, not just mail.

What I would avoid

Running Postfix/Dovecot yourself unless the goal is learning.

A modern mail stack is not hard to deploy. The hard parts are:

• getting Gmail/Microsoft to trust your IP
• monitoring reputation
• spam filtering
• backups
• patching
• avoiding compromised accounts

Self-hosting is excellent as a lab project; it is usually a poor choice for your primary identity. thesoftwarescout.com

Cheap shared hosting email is also usually a bad match:

• weak reputation
• limited DKIM controls
• poor automation
• noisy neighbors

If you also mean “programmatic provisioning”

If by self-service provisioning you mean:

“I want an API/CLI where I can create domains, mailboxes, aliases, rotate DKIM keys, etc.”

then the ranking changes. Look at more infrastructure-oriented platforms such as:

• Atriomail — API-driven provisioning, DNS automation, mailbox/domain management atriomail.com
• self-hosted Stalwart/Mailcow setups if you want infrastructure ownership

For a single developer, though, I would usually separate concerns:

• Human email: Fastmail
• Application email (password resets, alerts, receipts): a transactional provider like Amazon Web Services SES, Postmark, or Resend
• DNS: Cloudflare or Route 53
• Authentication: SPF + DKIM + DMARC from day one

My default stack for a solo developer would be:

Cloudflare DNS → Fastmail for inboxes → SES/Postmark/Resend for app mail → DMARC reporting mailbox

That gives you control without making email operations your side job.

For a tech-savvy solo developer, Migadu would be my first pick. The key differentiator is that its API is unusually well suited to treating email hosting as infrastructure rather than a GUI-only service.

My shortlist

1. Migadu — best match

Migadu exposes APIs for domains, mailboxes, identities, aliases, forwarding, DNS-record discovery, diagnostics, and activation. You can create a domain with external DNS, retrieve the exact MX/SPF/DKIM/DMARC records required, run diagnostics, and activate it programmatically. www.migadu.commigadu.com

That makes a workflow like this practical:

Terraform/script → create domain → create mailboxes/aliases → retrieve DNS requirements → update Cloudflare DNS → run diagnostics → activate

Importantly, Migadu explicitly supports external DNS, so you retain control of DNS rather than having to move your nameservers. www.migadu.commigadu.com

Migadu API documentation

2. Fastmail — best if you value UX more than automation

Fastmail is excellent if you want a mature, polished mail client/service while keeping DNS somewhere like Cloudflare. It supports externally hosted DNS, gives you the records to configure, and handles DKIM/SPF and related checks. www.fastmail.help

The downside for your particular requirements is self-service provisioning isn't as infrastructure-oriented as Migadu's API. I'd choose Fastmail if you're managing one or a handful of addresses manually rather than building an automated domain/mailbox provisioning workflow.

Fastmail custom domains

3. Zoho Mail — capable middle ground

Zoho has solid domain administration, including MX/SPF/DKIM/DMARC configuration and APIs for domain operations and DKIM management. www.zoho.com

I'd put it behind Migadu for a developer-centric setup because Zoho's ecosystem and admin model are more oriented toward conventional organizations than "I want to script my mail infrastructure."

Zoho Mail developer/API documentation

What I'd actually use

Cloudflare DNS + Migadu mail hosting is probably the sweet spot for your requirements:

• Keep authoritative DNS entirely under your control.
• Use Migadu for MX/mail transport.
• Publish Migadu's DKIM CNAMEs yourself.
• Set your own DMARC policy and reporting address.
• Automate mailbox/alias/domain creation through Migadu's API.
• Use DNS-as-code if you want reproducibility.
• Keep the domain registrar independent from the mail provider.

If you're only hosting your own 5–20 addresses/aliases and don't need provisioning automation, I'd instead pick Fastmail for the substantially nicer day-to-day experience.

Bottom line: Migadu for "email as infrastructure"; Fastmail for "email as a polished service."

For a tech-savvy solo developer, I’d prioritize providers that let you keep DNS at your registrar, expose the underlying mail standards cleanly, and don’t force you into a productivity suite.

My shortlist

1. Fastmail — my recommendation.
Fastmail is particularly nice for a developer because you can leave DNS at Cloudflare/your registrar and simply point MX records at Fastmail. Their setup explicitly supports externally hosted DNS, with SPF, DKIM and DMARC records that you manage through your DNS provider. www.fastmail.help

It also gives you IMAP, SMTP and JMAP, aliases, catch-all addressing, and a polished UI without dragging you into Google/Microsoft-style collaboration software.

Fastmail custom-domain documentation

2. Purelymail — if you enjoy minimal infrastructure.
Purelymail is unusually attractive for a solo developer: very inexpensive, custom domains, and no per-mailbox pricing. Its setup assumes that you control DNS and configure MX/SPF/DKIM/DMARC yourself. github.com

The tradeoff is that it's much less polished than Fastmail. I'd choose it if cost and technical simplicity matter more than UX.

3. Migadu — if “one domain” turns into “a bunch of domains.”
Migadu is worth considering if you expect to operate multiple personal/project domains. Its pricing model is based more on overall usage than charging separately for every mailbox, making it attractive to domain-heavy users. folioinbox.com

4. Zoho Mail — solid conventional alternative.
Zoho Mail has particularly good domain administration: its admin console exposes MX, SPF, DKIM and DMARC status, plus catch-all, aliases and other domain settings. www.zoho.com It's a good choice if you might eventually want conventional business-admin features.

What I'd choose

For your stated requirements:

Fastmail > Purelymail > Migadu > Zoho

If you're running one personal/developer domain, I'd pay for Fastmail and keep DNS at Cloudflare (or wherever you already manage DNS). You get the important separation:

registrar/DNS → your control
mail hosting → Fastmail

That means moving providers later doesn't require moving your domain or DNS infrastructure.

If you want the most control per dollar, go Purelymail. If you expect to have 5–20+ domains, I'd look much harder at Migadu.

For a tech-savvy solo developer, I’d shortlist these three:

1. Fastmail — my default recommendation

Fastmail

Fastmail fits your requirements particularly well. You can keep DNS at your own registrar/DNS provider, point MX at Fastmail, and manually manage the required MX/SPF/DKIM/DMARC records. Its domain interface also gives you aliases, catch-alls, multiple domains, and routing controls. www.fastmail.help

For a developer, I particularly like that you aren't forced to surrender DNS authority: Fastmail explicitly supports the "nameservers elsewhere, MX pointing to Fastmail" setup. www.fastmail.help

Pick it if: you want a polished mailbox with strong technical controls and don't want email administration to become a hobby.

2. Migadu — best if you're going to have lots of addresses/domains

Migadu

Migadu is unusually attractive for a solo developer running several projects. Its model is centered around domains and addresses rather than charging you for every individual address. It supports standard SMTP/IMAP/POP3 and explicitly positions itself as standards-oriented hosting. migadu.com

Pick it if: you have me@, hello@, support@, billing@, disposable project addresses, and potentially several domains and want them managed under one account.

3. MXroute — best for the "I want to administer my mail server" personality

MXroute

MXroute gives you a fairly traditional hosting control panel: add domains, create mailboxes, retrieve the domain-specific DNS configuration, and manage accounts yourself. Its documentation explicitly covers SPF, DKIM and DNS testing. docs.mxroute.com

Pick it if: you value administrative control and conventional mail-hosting mechanics over a particularly slick consumer mailbox experience.

What I'd choose

Fastmail for one primary personal/developer domain.

Migadu if you're likely to accumulate multiple domains/projects.

MXroute if you enjoy the infrastructure side and want a more traditional hosting-control-panel experience.

One important distinction: "full DNS control" is mostly about where your DNS is hosted, not which mail provider you choose. I'd keep DNS with something like your preferred authoritative DNS provider and have the mail host give you the MX/DKIM/SPF records. That keeps your web stack, DNS, and email independently replaceable. Fastmail explicitly supports this architecture. www.fastmail.help

For DKIM/DMARC specifically, all three can work; I'd configure DMARC yourself rather than blindly accepting the provider's most permissive default. Fastmail, for example, documents DKIM and a DMARC record as part of its manual DNS setup. www.fastmail.help

My ranking for your stated requirements: Fastmail > Migadu > MXroute.

For your profile, I’d shortlist these:

1. Migadu — my pick

Migadu

Migadu is unusually well suited to a developer who wants to treat email infrastructure like infrastructure. Its API can create/update domains, mailboxes, identities, aliases, and forwarding rules, and it can return the DNS records required for a domain. You can explicitly use external DNS rather than handing DNS hosting to Migadu. migadu.com

That makes a setup like this practical:

domain → Cloudflare DNS → Migadu

while your provisioning script/API manages:

• you@example.com
• billing@example.com
• aliases
• forwarding
• additional domains
• mailbox creation/deletion

Migadu's API documentation specifically exposes domain, mailbox, identity, forwarding, and alias CRUD operations. migadu.com

For a solo developer who might eventually automate everything with Terraform-esque scripts or a small CLI, this is the one I'd investigate first.

2. Fastmail — best if UX matters more

Fastmail

Fastmail is the nicer choice if you want excellent mail/calendar/contact UX and don't need your provisioning system to control every aspect of the account.

You can keep your DNS at your registrar rather than transferring nameservers, and Fastmail supports DKIM/SPF and other domain-security configuration. www.fastmail.help It also supports multiple domains, aliases, catch-alls, and lots of address-management functionality. www.fastmail.com

It has a developer API based around JMAP and other open protocols. www.fastmail.com

Tradeoff: it's more of a polished email product than an email-infrastructure API. For one person, that's arguably a feature.

3. Purelymail — best value

Purelymail

If your attitude is "email should be boring and cost almost nothing," Purelymail is compelling.

Custom domains have no additional charge, and it supports SPF, multiple DKIM keys, and DMARC. purelymail.com You manage the DNS yourself, so there's no loss of control over your domain. imap.purelymail.com

The downside for your particular use case is automation: its provisioning story isn't nearly as developer/API-oriented as Migadu's.

My ranking for you

1. Migadu — if API-driven provisioning is important
2. Fastmail — if you prioritize the best overall mail experience
3. Purelymail — if price and simplicity dominate

One architectural recommendation: keep authoritative DNS somewhere independent (e.g. your registrar/Cloudflare) and have the mail provider give you MX/SPF/DKIM records. That gives you a clean escape hatch: changing mail hosts becomes a DNS change rather than a migration of your domain's entire DNS infrastructure.

For your stated requirements, Migadu + external DNS is probably the sweet spot. migadu.com

For a tech-savvy solo developer, I’d narrow it to Migadu, Purelymail, and Fastmail. Your emphasis on DNS control + DKIM/DMARC + self-service provisioning pushes me away from Google Workspace/Microsoft 365 unless you specifically want their productivity suites.

🥇 Migadu — my pick for you

Migadu is probably the closest match to what you described.

Its API exposes domain management and, importantly, lets you retrieve the exact DNS records needed for a domain—including MX, SPF, DKIM and DMARC. migadu.com

That makes it attractive if your mental model is:

terraform/app script → create domain → get DNS requirements → create mailboxes/aliases → done

It's particularly compelling if you expect to operate multiple domains, aliases, or automated mailboxes, rather than just having me@example.com.

Migadu API documentation

🥈 Purelymail — best value

Purelymail is remarkably inexpensive and unusually friendly to people who actually want to manage their own DNS.

You keep DNS at your registrar/DNS provider, and Purelymail gives you the MX, SPF, three DKIM CNAMEs, and DMARC records to publish yourself. imap.purelymail.com

Its big advantage is price: the current Simple plan is $10/year, with custom domains included and no per-domain/per-user charge under its fair-use model. imap.purelymail.comfolioinbox.com

I'd choose this if you're comfortable trading some polish for absurdly low cost and lots of control.

Purelymail custom-domain documentation

🥉 Fastmail — best overall UX

Fastmail is my recommendation if "self-service" means I want everything easy to administer myself, rather than I want to automate the administration through an API.

You can leave DNS at your existing provider and publish the required MX/SPF/DKIM/DMARC records yourself. Fastmail explicitly supports custom domains with externally hosted DNS. www.fastmail.help

It's the one I'd pick if this is primarily your personal production mailbox and you care about a really good webmail/client experience, aliases, calendar/contacts, IMAP/JMAP, etc.

Fastmail custom-domain documentation

My ranking for your requirements

If API-driven provisioning matters:
Migadu > Purelymail > Fastmail

If low cost matters:
Purelymail > Migadu > Fastmail

If day-to-day email UX matters:
Fastmail > Migadu > Purelymail

If you want to own/control DNS independently of the mail provider:
All three work well. I'd keep DNS at Cloudflare or another independent DNS provider, rather than delegating nameservers to the mail host. Fastmail explicitly supports this arrangement. www.fastmail.help

Bottom line: I'd start with Migadu for a developer-oriented setup. Its API/DNS-record workflow is the differentiator that most closely matches your "self-service provisioning" requirement. If you're only ever going to have one domain and a handful of addresses, Fastmail is probably the nicer choice; if cost is paramount, Purelymail is hard to beat.

For a tech-savvy solo developer, I’d prioritize DNS independence, standards-based email, easy domain/user provisioning, and good deliverability tooling over collaboration-suite features.

My shortlist

1. Migadu — my first choice

Migadu

Migadu is unusually well suited to a developer who thinks of email as infrastructure rather than an office suite. It supports standard SMTP, IMAP and POP3, unlimited addresses/domains on its higher plans, multi-admin access, domain/mailbox limits, domain-health monitoring, catchalls, and no proprietary client requirement. migadu.comwww.zoho.com

The particularly nice part is the domain-centric administration model: add a domain, configure its DNS, then create whatever addresses you need. That's convenient if you have me@, hello@, billing@, security@, etc., or several side-project domains.

Pick Migadu if: you expect to have multiple domains or aliases and want a fairly "Unix-y" email-hosting experience.

2. Purelymail — best if cost matters

Purelymail

Purelymail is extremely appealing for a solo developer. Custom domains cost nothing extra, and its setup explicitly has you control the DNS at your registrar. Its documented setup uses MX, SPF, DKIM and DMARC, with DKIM selectors exposed as DNS records and DMARC configured through DNS. support.purelymail.com

It's also deliberately uncomplicated: you bring your domain, manage its DNS yourself, and Purelymail provides the mail infrastructure.

Pick Purelymail if: you want "email hosting as a utility" and don't care about having a fancy collaboration suite.

3. Fastmail — best polished option

Fastmail

Fastmail is the one I'd choose if you want excellent email UX but don't want Google/Microsoft. You can keep DNS at your registrar; Fastmail provides setup guidance and supports the usual authentication/security records. It can also host DNS itself, although you don't have to use that option. www.fastmail.help

Pick Fastmail if: this is primarily your personal mailbox and you value the client/UI more than infrastructure flexibility.

4. Zoho Mail — good if you're building a tiny business

Zoho Mail

Zoho has a much more extensive admin console. You can bring an externally registered domain, manage users, and see/configure MX, SPF, DKIM and DMARC status from the domain administration interface. www.zoho.com

It's more "business email platform" than "developer email plumbing," though.

What I'd actually choose

For your requirements:

1. Migadu — best overall
2. Purelymail — best minimalist/value choice
3. Fastmail — best polished personal-email experience
4. Zoho Mail — best if you anticipate business/admin requirements

If by "self-service provisioning" you specifically mean API/CLI-based creation of domains, mailboxes and aliases, rather than just an admin UI, I'd narrow the field further before you commit. That's an important distinction: plenty of providers give you DNS/DKIM/DMARC control but aren't particularly automation-friendly.

For a tech-savvy solo developer, I’d prioritize providers that let you keep DNS authoritative at your registrar/Cloudflare and give you straightforward domain-level controls.

My shortlist

1. MXroute — my pick

MXroute

This is probably the closest match to your requirements. You keep DNS at your own provider, while MXroute gives you a management panel for domains and exposes the MX/SPF/DKIM values you need. It also documents DMARC configuration and has a built-in DNS tester. docs.mxroute.com

It's particularly appealing if you expect to have several domains, aliases, catch-alls, or developer infrastructure around your email.

2. Purelymail — best value

Purelymail

Very developer-friendly and unusually inexpensive. You explicitly manage the DNS records yourself: MX, SPF, three rotating DKIM records, and DMARC. Purelymail also uses a DNS ownership record so that someone can't simply recreate your domain in another account if you delete yours. imap.purelymail.com

I'd choose this if cost and owning the plumbing matter more than having a particularly polished product.

3. Fastmail — best UX

Fastmail

Fastmail is the one I'd pick if you want something that feels more like a polished mainstream mail product while retaining proper domain control. You can leave nameservers at your existing DNS provider and simply point MX at Fastmail; their setup wizard gives you the required SPF/DKIM records, and you can publish your own DMARC policy. www.fastmail.help

The downside for your particular use case is that it's somewhat less infrastructure-oriented than MXroute/Purelymail.

What I'd actually do

If this were my domain:

Cloudflare DNS → MXroute → IMAP/SMTP client

Then I'd publish:

• MX → MXroute
• SPF → MXroute
• DKIM → MXroute-generated key
• DMARC → initially p=none, with reporting enabled
• Later move to p=quarantine or p=reject once I've verified all legitimate senders

That gives you a clean separation: you own the domain and DNS; the mail host just provides mail infrastructure.

Ranking for your stated priorities:
MXroute > Purelymail > Fastmail > Migadu.

If you want, I can also compare MXroute vs Purelymail specifically for a developer running multiple domains, transactional email, aliases, catch-alls, and automated provisioning.

For your requirements, I’d prioritize API/admin automation and keeping DNS at your registrar, rather than a polished office suite.

My picks

1. Migadu — my recommendation

Migadu is unusually well matched to a solo developer who wants to treat email infrastructure almost like another service in their stack.

Its API can create domains, create/delete mailboxes, manage aliases and forwarders, retrieve the required DNS records, run DNS diagnostics, and activate domains. It also explicitly supports using external DNS, which is what I'd choose if you want Cloudflare/your registrar to remain authoritative. www.migadu.commigadu.com

The particularly nice part is the DNS workflow: the API exposes the DKIM CNAMEs, SPF, DMARC, MX and verification records, then gives you a diagnostics endpoint before activation. www.migadu.commigadu.com

So you could build something like:

domain purchase → DNS automation → Migadu API → create mailbox/aliases → DNS diagnostics → activate

That's about as close as you'll get to email-as-infrastructure without running your own mail server.

One caveat: Migadu describes its API as early beta, so I'd test the exact operations you need before making it a critical dependency. www.migadu.commigadu.com

2. MXroute — worth a serious look

MXroute has a current API with explicit operations for domain management, email accounts, forwarders, and domain pointers. api.mxroute.com

I'd choose it over Migadu if your priority is straightforward mailbox hosting plus programmatic administration, rather than Migadu's particularly nice DNS/diagnostics workflow.

3. Fastmail — if automation is secondary

Fastmail is probably the nicest product here for actually using email. You can keep your DNS elsewhere and manually publish MX/SPF/DKIM/DMARC records; Fastmail documents that workflow explicitly. www.fastmail.help

It also supports custom-domain aliases, catch-all addresses, and routing. www.fastmail.help

But for "I want to provision this domain/mailbox programmatically", I'd put Migadu/MXroute ahead of it.

What I'd do

If this were my solo-dev setup:

Cloudflare DNS + Migadu

Keep DNS completely independent of the mail provider, manage the DNS records yourself, and use Migadu's API for mail infrastructure. That gives you maximum control without taking on the deliverability/maintenance nightmare of self-hosting SMTP.

And I'd publish DMARC initially as p=none, monitor reports, then move toward quarantine/reject once you've verified every legitimate sender. Fastmail's documentation describes the same progression and the role of DMARC in aligning SPF/DKIM. www.fastmail.help

Bottom line: Migadu is the strongest match for your exact requirements; MXroute is the alternative I'd evaluate alongside it. Fastmail wins if mail UX matters more than provisioning automation.

For a tech-savvy solo developer, I’d narrow it to three:

1. Migadu — my recommendation

Migadu is particularly well suited to the "I own several domains and want to administer them myself" mindset. It is standards-based—SMTP, IMAP, POP3 and webmail—with unlimited email addresses and domain-oriented pricing rather than charging you for every alias/address. migadu.com

That makes it attractive if you want things like:

• me@example.com
• github@example.com
• billing@example.com
• anything@example.com
• several separate project domains

without turning mailbox administration into a SaaS-management exercise.

Downside: the product is more utilitarian than Fastmail, and I'd verify the exact automation/API features you need before choosing it.

2. Fastmail — best if email itself matters

Fastmail is my pick if you want a really good mail client/service while retaining control of your domain's DNS. You can keep DNS at your registrar/DNS provider and publish the required MX, SPF, DKIM and DMARC records yourself. Fastmail documents three DKIM CNAMEs and a DMARC TXT record for custom domains. www.fastmail.help

It also gives you IMAP, SMTP and JMAP, which is unusually nice for a developer who wants programmatic access rather than being trapped in a proprietary client. www.fastmail.helpthesoftwarescout.comgithub.com

I'd choose Fastmail over Migadu if you're primarily operating one personal domain and care more about excellent day-to-day UX than about managing lots of domains.

3. Purelymail — compelling if you want cheap and simple

Purelymail is the interesting budget option. Its model is unusually friendly to developers with multiple domains: custom domains don't carry a separate fee, and its documentation explicitly covers MX, SPF, DKIM and DMARC configuration. github.com

The tradeoff is that it's a much smaller/minimalist service. I'd pick it for "email is infrastructure; give me standards and get out of my way", rather than "I want the nicest email service."

What I'd actually do

My ranking for your requirements:

1. Migadu — if you're going to have multiple domains/projects.
2. Fastmail — if it's primarily one domain and you want the nicest experience.
3. Purelymail — if minimizing cost is important.

I would not self-host SMTP unless running mail infrastructure is itself the hobby. The DNS/authentication part is easy; reputation, spam filtering, IP reputation, bounces, abuse handling and deliverability are where self-hosting becomes a time sink.

One other architectural recommendation: keep your DNS with a provider such as Cloudflare or your registrar rather than transferring DNS management to the mail host. Then your domain remains independent of the email provider, and moving from Migadu → Fastmail → something else is mostly an MX/DKIM/SPF/DMARC migration rather than a domain-management migration.

For a solo developer, that separation is probably the cleanest setup.

For a tech-savvy solo developer, I’d shortlist these:

1. Migadu — my recommendation

Migadu

Migadu is unusually well matched to what you're asking for. You can keep authoritative DNS at Cloudflare, Route 53, or wherever you like, while Migadu provides the MX/SPF/DKIM/DMARC configuration information. Its API can create/manage domains, mailboxes, identities, aliases, and forwarding rules, so you can automate provisioning rather than clicking around an admin UI. www.migadu.commigadu.com

It also doesn't force you into a "one paid seat = one mailbox" model; Migadu explicitly prices around usage and lets you have many addresses on your domains. migadu.com

Why I'd pick it: you can treat email almost like infrastructure:

Terraform / script / admin tool
          ↓
     Migadu API
          ↓
 domain → mailbox → aliases → identities
          ↓
your own DNS provider
          ↓
 MX / SPF / DKIM / DMARC

The one caveat is that Migadu describes its API as still being in beta and says not every function is exposed. www.migadu.commigadu.com

2. Purelymail — fantastic value

Purelymail

If you don't need sophisticated API-driven administration, Purelymail is compelling. Its current simple pricing is $10/year, with no hard limits on users, custom domains, or storage; it also supports unlimited mailboxes and aliases on domains you own. smtp.purelymail.com

It gives you explicit control over the DNS records: MX, SPF, three DKIM CNAMEs, and DMARC. support.purelymail.com

I'd choose it when cost and simplicity matter more than API automation. Its 2026 roadmap itself lists finer-grained API-key permissions as something it wants to improve, which is a hint that its automation story isn't as mature as Migadu's. news.purelymail.com

3. Fastmail — best UX

Fastmail

Fastmail is the one I'd pick if you care more about having a really polished personal email service than programmatically managing lots of mailboxes.

You can keep DNS external, and Fastmail supports DKIM/SPF and other email security configuration. www.fastmail.help It also has excellent standards support—JMAP, IMAP, SMTP, CalDAV, CardDAV, etc.—and a developer API. www.fastmail.com

The important distinction: its API is primarily oriented around accessing/managing mail and user data, rather than being a comprehensive "email infrastructure control plane" like Migadu's domain/mailbox/alias API. Fastmail explicitly documents APIs for mail, submission, contacts, calendars, and masked addresses. www.fastmail.com

What I'd do in your shoes

Cloudflare DNS + Migadu would be my first choice.

That gives you:

• 🛠️ Full authoritative DNS control
• 🔐 DKIM + SPF + DMARC under your control
• 🤖 API-driven mailbox/alias provisioning
• 📬 Normal IMAP/SMTP
• 🌐 Multiple domains without maintaining mail servers
• 🔄 Easy migration away later because you're using standard protocols

I'd avoid self-hosting Postfix/Dovecot unless operating mail infrastructure itself sounds fun. For a solo developer, the ongoing deliverability, reputation, spam filtering, backups, IP reputation, and abuse-management work generally isn't worth the opportunity cost.

Ranking for your exact requirements: Migadu > Purelymail > Fastmail.