Invental/ Writing/ The two-week sprint contract
Process — 18 · Jan · 2026 · 5 min read

The two-week sprint contract — our engagement model, written out.

No hourly billing. No six-month contracts. Fixed-scope two-week sprints with clear deliverables and an exit after every cycle. Here's exactly how it works and why clients keep renewing.

AL
Anna L.
Daniyar K.
18 · Jan · 2026
The two-week sprint contract [ FIG. 001 ] — Process · Engagement INV-P-2026-01-18 Ship every
two weeks.

For the first five years of the studio, we billed hourly. Track time, send invoices, reconcile at the end of the month. It worked — technically. But it created a dynamic we didn't like: every conversation about scope was also a conversation about money. The client would ask "can you also fix this?" and pause, calculating whether the question was worth the billable time. We'd answer honestly but feel the friction. The meter was always running, and everyone knew it.

In 2023 we switched to a model we call the sprint contract. Fixed scope, fixed price, two-week cycles, with an exit ramp after every sprint. It changed everything about how we work with clients, and we're writing it out here so prospective clients know exactly what they're signing up for.


§ 01Why we stopped billing hourly

Hourly billing has three problems that compound over time:

It penalizes efficiency. If we solve a problem in two hours instead of ten, we earn less. The incentive structure rewards slow work, and while we never padded hours deliberately, the system's incentive is fundamentally misaligned with the client's interest.

It creates anxiety about communication. Clients hesitate to send messages, ask questions, or request small changes because every interaction costs money. The best client relationships we've had were the ones where communication was free-flowing. Hourly billing chokes that flow.

It makes cost unpredictable. The client gets an estimate at the start and a surprise at the end. Even with good tracking and regular updates, the final number is never exactly what was estimated. That unpredictability erodes trust, even when the overrun is justified.

The best client relationships are the ones where asking a question doesn't start a billing clock.
— Internal process review, 2023

§ 02How a sprint works

A sprint is two calendar weeks — ten business days. Here's the rhythm:

Day 1 (Monday): Sprint planning. A 60-minute call where we review the backlog, agree on the sprint's deliverables, and write them down in a shared document. Every deliverable is phrased as a user-visible outcome: "Checkout flow handles multi-currency," not "Implement currency conversion logic." By the end of the call, the client knows exactly what they'll have on Day 10.

Days 2-9: Build. We work. The client gets access to a staging environment that updates continuously. We post daily async updates in Slack — what shipped, what's in progress, what's blocked. If something is blocked on the client (an API key, a design decision, content), we flag it immediately. Blocks don't wait for the next standup.

Day 10 (Friday): Sprint review. A 45-minute call where we demo everything that shipped, review anything that didn't, and discuss the next sprint. The client sees working software, not slides. If they want to continue, we plan the next sprint. If they don't, we hand over the code and documentation. No hard feelings, no penalties, no exit fees.

If the client wants to stop, they stop. No penalties, no exit fees.

— Sprint contract, Section 4

§ 03What's included

Every sprint includes:

§ 04What's not included

A few things sit outside the sprint scope:

§ 05Why clients renew

Our renewal rate is around 90% — meaning nine out of ten clients who complete a sprint sign up for the next one. We've thought about why this is, and we think it comes down to three things:

They see working software every two weeks. Not mockups, not prototypes — deployed, working software that real users can touch. The feedback loop is fast enough that the product improves visibly from sprint to sprint, and the client can feel the momentum.

They can stop anytime. Paradoxically, the ability to leave makes clients more comfortable staying. There's no sunk cost pressure, no contractual inertia. Every renewal is an active choice, which means both sides are in the engagement because it's working, not because the contract says so.

The cost is predictable. The client knows exactly what each sprint costs before it starts. There are no surprise invoices, no scope-creep surcharges, no "we went over estimate" conversations. Budgeting is simple: multiply the sprint cost by the number of sprints in the roadmap.

§ 06When this model doesn't fit

The sprint model works best for product development — building features, shipping improvements, iterating on a live product. It doesn't work well for:

For everything else — new product development, feature buildouts, migrations, redesigns — two-week sprints with a clean exit after each one have been the best working arrangement we've found. The client gets predictability. We get focus. Both sides get the freedom to walk away if it's not working. That's the whole model.


— End of essay. Want to try a sprint? Start a project →

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