A SaaS development company that prices the build before it starts
Deepsel is a SaaS development company for founders and small businesses who want a subscription product built and want to know the price first. We design and build multi-tenant products with accounts, card billing, roles and usage limits in the first version, then run them in production. You log in to a working version every two weeks. The code lives in your own accounts, and the prices are on this page. The tenant and payment problems you're about to hit are ones we've already solved for a live marketplace.
What custom SaaS development is, and who hires it
Custom SaaS development is building a web product that other companies pay for by subscription, to your design, instead of assembling it from no-code blocks or renting a white-label kit. The feature your customers log in for is the part everyone plans. The work that separates a SaaS from an ordinary web app is everything around it: keeping each customer's data apart, charging cards every month without you touching an invoice, deciding who inside a customer's team can see what, and limiting what each plan can do.
Those pieces are the same whether you sell to dentists or to freight brokers. They're also where a first version goes wrong when a builder treats it like a website. You're most likely in one of these three spots:
A spreadsheet or no-code tool your customers already pay for
You run a process for other companies in Airtable, Bubble or a shared sheet, and they'd pay monthly for a real product. What's missing is accounts, card billing and a wall between one customer's data and the next.
A vibecoded or freelancer-built prototype with users on it
The demo works. People are signing up. Nobody designed the sign-in, the payments or the wall between customers, and the next ten signups will find that out before you do.
An operating business with a product idea in its own trade
You know the workflow better than any developer ever will. What you need is a team that asks sharp questions about your trade, says no to the wrong features, and builds the subscription product your peers will pay for.
You shouldn't have to take our word for anything. The price is on this page, the scope is written before the build starts, you see a demo every two weeks, and the code sits in accounts you control from day one.
What a SaaS build includes, and by when
Deepsel's SaaS development services come with the subscription machinery built in from the start. Each item below is a line in the written scope, so you can see it, price it and strike it.
Multi-tenancy
Each customer company sees only its own data. We enforce the boundary in the database and cover it with tests, and we pick the isolation model (shared tables, a schema per customer, or a database per customer) for your security needs and your hosting bill.
Subscription billing
Plans, trials, seats, mid-month upgrades, failed cards, invoices, sales tax and cancellation. Built on Stripe Billing or a merchant of record such as Paddle. You choose, with the fee table in front of you.
Roles and permissions
Owner, admin, member, read-only, plus the invitations and removals that go with them. We decide these in the data model before the first screen exists, because bolting roles on later means touching every page.
Usage limits and plan gating
What the free plan can't do, what happens when a customer crosses a limit, and how an upgrade turns the feature on without a support ticket.
Onboarding and the back office
The self-serve path from signup to first value, and an admin screen where you see every tenant, its plan, its usage and its failed payments without asking an engineer.
Operations
Monitoring, alerts, backups, a staging environment and a deploy that can roll back. The parts that let you sleep once strangers are paying.
By when
A typical startup MVP ships inside 1 to 2 months on our Technical Leadership retainer. A SaaS first version carries billing, tenancy and roles on top of the core workflow, so plan on the top of that window. The written estimate names the month before we start, and the two-week demos show you whether it's holding.
For comparison, Forcoda's 2026 guide puts a standard SaaS MVP at 8 to 16 weeks, and a review of 17 published timelines found a median claim of 8 to 12 weeks (September 2026). Those are builders' claims, and so is ours. Ours comes with a refund rule.
What you hold at the end
- A product customers can sign up for, pay for and use without you in the loop.
- Repos, cloud accounts and the Stripe account in your name, with access from day one.
- Architecture notes and a runbook a future engineer can follow.
- Automated tests for sign-in, tenant isolation, billing and the core workflow.
- A monthly scorecard of what shipped and what slipped, in plain English.
- A roadmap for version two, built from what the first customers asked for.
Custom SaaS development pricing, published and month-to-month
Three plans, no setup fee, no minimum term. Which one you start on depends on what you already have. If you need a tech lead plus several engineers on parallel workstreams, that's a custom Scale plan, so ask.
Technical Leadership
$15,000 / month
A fractional CTO who takes charge of your technology and answers for it personally, plus the senior engineers who design, build and ship the SaaS.
- Architecture, roadmap and product decisions
- Senior engineers who build and demo every two weeks
- Investor and tech-diligence support
- Monthly plain-English scorecard
For founders starting from a spreadsheet, a deck or a prototype, with nobody on the team to own the technical side.
Senior Product Engineer
$4,000 / month half-day, or $8,000 / month full-time
One dedicated senior engineer. A demo every two weeks and a daily overlap window with US hours.
For companies that already have a technical lead and need the SaaS built or extended by someone senior.
Rescue Sprint
$3,000 fixed, one week
One week, one time, for a prototype or codebase that exists but you can't trust yet.
- Full audit of product, code and architecture
- Critical bugs and security holes fixed and shipped
- Plain-English scorecard and roadmap, yours to act on with Deepsel or anyone
Start here if users are already on a vibecoded, no-code or freelancer-built version.
What a SaaS build costs at Deepsel, with the arithmetic
Starting from nothing, nobody to own the technical side. The Technical Leadership retainer is $15,000 a month (a fractional CTO plus the engineers), and a typical startup MVP ships inside 1 to 2 months, so $15,000 to $30,000. A SaaS first version sits at the top of that window because billing, tenancy and roles come with it. If the written scope needs a third month, that's $45,000, and you'll know before we start. Then you step back to $0 a month, or keep one senior engineer on at $4,000 or $8,000.
You already have a technical lead. Skip the retainer. One full-time senior engineer is $8,000 a month, so three months is $24,000. A half-day engineer is $4,000 a month. The written estimate names the months.
You have a prototype or a codebase. The $3,000 sprint comes first. One week later you hold a scorecard that says which of the two routes above you're on, and how much of what exists survives. If the developer who built it has gone quiet, our software project rescue page covers the takeover.
For comparison, agencies that publish SaaS prices put a first version at $40,000 to $90,000 (Classic Informatics, fetched October 2026) or $30,000 to $150,000 (Brocoders, October 2026), and Ardura's April 2026 table lists a SaaS platform at $40,000 to $100,000 over 10 to 16 weeks with a team of five to seven. Ours is lower for two reasons: the engineers work from Hanoi on a flat monthly retainer, and the first version is scoped to what wins early customers. Senior engineers in Vietnam who can design a system aren't cheap. We don't hire the ones who are. The full breakdown of SaaS development cost has the whole market table, plus payment fees and hosting after launch; for a first product without tenancy and billing, read the MVP development cost guide instead.
Guarantees on every plan
- Month-to-month, 30 days' notice, no termination fees.
- First 30 days: full money-back guarantee.
- IP yours from the first commit under a US-jurisdiction agreement; repos and servers in your own accounts.
- Any engineer replaced within 7 days if not a fit.
- Happiness Index: you score us every month on delivery, accepted work and incidents. A month under 50 is refunded.
How a SaaS build runs at Deepsel, and what you hold after each step
Five steps. Each one ends with something in your hands that's useful even if you stop there.
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Discovery call
Thirty minutes with Tim, free. We ask what you're building, who pays for it, and what already exists.
You hold: An honest read on what you have and what the first version should contain, and it's yours whether or not we work together.
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Scope and estimate
We map tenants, plans, roles, workflows and integrations, then put the scope, architecture, timeline and price in writing. If a prototype or codebase already exists, this step becomes the $3,000 one-week sprint instead.
You hold: A written scope and estimate you can take to any builder, or, after a sprint, the critical fixes shipped plus a plain-English scorecard and roadmap.
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Design
Screens and the data model, drawn together: which objects belong to a tenant, what each plan allows, who can see what.
You hold: Clickable screens and a data model you've approved. What you signed off is what gets built.
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Build in two-week cycles
Senior engineers build and test. Every two weeks you log in to a working version, and every month you get a scorecard of what shipped, what slipped and why.
You hold: A product you can open at any time, in repos and cloud accounts in your name, with automated tests and a changelog.
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Launch and after
A staged rollout with a rollback plan, documentation and a handover session. Then we run the product, or your team does.
You hold: A SaaS your customers can sign up for, pay for and use without you, plus the runbook. Step back to $0 a month, or keep an engineer on.
That's how we run every build. The repo is yours on day one, the backlog is shared, and the demo lands every second week against the scope you approved. The change rule fits in one sentence: anything outside the written scope gets priced in writing before anyone builds it, and you say yes or no.
SaaS development proof you can open, with multi-tenant accounts, payments and a federal login
The clearest proof we can offer is the same work, already live for other people. Open it before you sign.
Tenants, payments and sign-in, already live
Clubloungery is a booking marketplace for nightclubs, and it's shaped like a SaaS. Each venue owner has an account, uploads a floorplan and draws the bookable lounges onto it, so no developer is needed to onboard a new venue. Guests pick a lounge on the plan, reserve in a few clicks and pay a deposit. Cancellation windows and no-show handling are built in. Per-venue data and payments in one codebase: that's the tenant and billing work from the "what you get" section above, built and in use.
Sign-in at scale is the central login of the Swiss federal administration. It authenticates federal staff, cantonal partners and companies filing electronically, so taking it offline was never an option. We replaced the whole front end in stages while the system stayed live, with zero downtime during the switchover and the backend untouched. A login that can't go down teaches you where the unglamorous lines belong. That's why the scope we write for you has them.
Client products in production
- Clubloungery, a booking marketplace for nightclubs: each venue owner uploads a floorplan, draws the bookable lounges and takes deposits, with cancellation windows and no-show handling built in. Per-venue data and payments, the same shape as a SaaS tenant.
- eIAM, the central login of the Swiss federal administration: the whole front end replaced while the system stayed live. Sign-in for federal staff, cantonal partners and companies filing electronically, with zero downtime during the switchover.
- FitFoodies, a consumer app that finds healthy dishes nearby on a live map, filtered by diet and nutrition.
- Gemina AI, our own developer tool from 2023 to 2024, one of the first AI coding assistants that understood a whole codebase on disk.
The write-ups, with screenshots, are on the projects page.
The people
I'm Tim Tran, Deepsel's founder, and I lead every engagement myself. Khuong Pham (7+ years, full-stack React and Python) and Trang Hoang (QA, 6 years, test automation) do the building and the testing. The team works from Hanoi, Vietnam, on a daily overlap window with US hours, under Deepsel Inc., a Delaware company, and we keep it small on purpose: three senior people, a handful of retainer clients at a time, and a waitlist when we're full. The person on the discovery call is the person who writes the code. More on the about page.
Custom SaaS development vs no-code, a freelancer, a large agency, AI tools and hiring
Each of these is the right answer for somebody. Here's when.
No-code (Bubble, Airtable, Softr)
The right call for your first ten customers if you can build it yourself. The limits show up at billing, roles and per-customer data, and in the per-seat fees once one customer has forty users. If you arrive with a no-code version that has done its job, we treat it as the spec; our MVP development page covers the handover.
A freelancer
Fast and cheap for a defined feature. Founders who went this way for a whole product report paying $2,500 to $20,000 for a first version, and the trouble came afterwards: "Bug fixes took weeks because the freelancers had moved on to other projects" (r/SaaS, March 2026). Nobody owns the architecture, the security, or what happens on a Saturday.
A large agency
A project manager sits between you and the engineers, and the senior person from the sales call is rarely the one writing the code. Their published price bands are in our SaaS development cost guide. Before you sign with one, our guide on how to choose a software development company lists the questions to ask.
Build it yourself with AI tools
Founders report spending $25 to $1,500 in Lovable, Replit or Cursor credits to reach a working demo, plus months of their own time. Where it stops is the same every time: tenant isolation, payments, sign-in security and a deploy that holds. If that's where you are, the $3,000 sprint picks up from there, and our AI MVP development page explains what gets checked.
Hiring in-house
The median US software developer earned $135,980 in May 2025 (Bureau of Labor Statistics), and benefits add about 30% of employer cost on top (BLS, June 2026). One developer is also one person: no QA, no second opinion on the architecture, and a hiring search before anything ships. The right move once the product has revenue to carry a team. Our software development for startups page compares the routes.
A good fit
- Founders with paying customers on a spreadsheet or no-code tool who need the real product.
- Owners of operating businesses building a subscription product for their own trade.
- Founders with a vibecoded or freelancer-built version that has to hold up for the next hundred customers.
- Funded teams who want the SaaS shipped by senior engineers while they hire.
Buy something else
You have an idea and no budget yet. Build the demo yourself with AI tools, get a few people using it, then come back for the $3,000 sprint. We'd rather meet you then.
You need ten engineers next month. We're three senior people with a short client list. A larger shop is the right buy, and our list of small software development companies for startups names some.
Your product is a mobile app first. We build those too, but a SaaS back office with a thin app on top is a different scope from an app-store product, and we'll tell you which one you're describing on the call.
SaaS development questions founders ask
How much does custom SaaS development cost?
Agencies that publish prices put a SaaS first version at $30,000 to $150,000. At Deepsel a typical startup MVP ships inside 1 to 2 months on the $15,000-a-month Technical Leadership retainer, so $15,000 to $30,000, with a SaaS build at the top of that window. Our SaaS development cost guide has every published range with its source, what founders report paying, payment fees and hosting.
How long does it take to build a SaaS product?
Forcoda's 2026 guide puts a standard SaaS MVP with auth, billing, a dashboard and a few integrations at 8 to 16 weeks, and a review of 17 published timelines found a median claim of 8 to 12 weeks. At Deepsel a typical startup MVP ships inside 1 to 2 months. A SaaS first version with billing and tenancy sits at the top of that window, and the written estimate names the month before we start.
What is the difference between SaaS development and web app development?
A web app serves users. A SaaS product serves paying companies, so it also has to keep each customer's data apart, charge cards every month, manage who inside a customer can see what, and limit what each plan can do. Those four pieces are the SaaS-specific work, and they're the expensive ones to add after launch. One agency puts it plainly: data isolation "has to hold at the database level. That is an architecture decision, and it is expensive to bolt on later."
Can you turn my no-code or vibecoded prototype into a real SaaS?
Yes, and we start by not throwing it away. The $3,000 one-week sprint audits what exists, fixes the critical bugs and security holes, and gives you a scorecard that says what holds and what has to be rebuilt. You decide the next step with that in hand, with us or with anyone else.
Who owns the code, the Stripe account and the servers?
You do, from the first commit, under a US-jurisdiction agreement with Deepsel Inc., a Delaware company. Repos, cloud accounts and the payment account are opened in your name. Leaving is a decision, not a migration project.
Do you build the AI features too?
Yes. In most SaaS builds the AI feature is the smaller share of the work; accounts, billing, onboarding and admin are the larger share, and other agencies report the same split. We build the model calls, the evaluation set and the monthly cost controls together. Our AI MVP development page covers the prices.
Is a SaaS product development company different from a SaaS app development company?
Same job, different labels. "SaaS app development" usually means the build. "SaaS product development" adds the scoping, design and roadmap decisions around it, and "SaaS development services" is the catch-all. Here you get all of it from one team, and the person who makes the decisions is the person responsible for shipping them.
Where is the team, and how do we work across time zones?
Deepsel Inc. is a Delaware company. The engineers work from Hanoi, Vietnam, with a daily overlap window on US business hours for calls and demos. Everything is in English, and Tim Tran, the founder, leads every engagement himself.
What happens after launch?
The same people who built it run it, for as long as you want: monitoring, patches and the next features, month-to-month. Or we hand it to your team with documentation and a walkthrough. Either way the code, the accounts and the runbook are already yours, so nothing has to be migrated.