Slipstream ER vs ByteBloc — the 1989 incumbent vs the 2026 build

ByteBloc solved emergency department scheduling before most of today’s ED directors started residency. The product’s own line is “Scheduling Emergency Providers since 1989,” and it was founded by an emergency physician.¹ As of August 2026 it still belongs to 3rd Millennium, Inc., a Massachusetts company that also sells DBI Software and Novi Survey. ByteBloc is one of three unrelated product lines, not the company’s sole focus.²

It is deployed in EDs in all 50 US states, Canada, and several other countries. The shift-relationship model it pioneered is why groups stayed. You configure rules and preferences, then auto-generate a draft to review and publish. In their own words: “Once configured, you should be able to create a schedule at the push of a button.”¹

The question is not whether that works. The question is what a scheduler built in 2026 does differently: a published price, a self-serve trial, fairness that carries across months, and a way to move a roster without waiting on a demo.

Side-by-side comparison

The table below is dated August 2026. ByteBloc wins the longevity row and the payroll-depth row on purpose. A product that has scheduled emergency providers since 1989, with payroll categories and rate variations baked in, is not a footnote. It is the incumbent for a reason.¹

Prefer to read pricing first? See published Core and Pro plans.

Where the difference actually shows up

Nobody leaves a 35-year scheduler because a newer homepage is cleaner. They leave because buying it, expressing the next rule, or getting a roster in and out has become harder than the month they are trying to publish.

Buying it

Slipstream ER publishes its price. Core is $49.99 a month for a single site of up to 30 providers. Pro is $99 a month for up to 50 providers and multi-site. The 30-day trial is self-serve and does not ask for a card.

ByteBloc does not publish a price. As of August 2026 there is no pricing page. The only public path is a demo request form. Note the wording carefully: that is a demo request, not a free trial.¹ For a group that already knows how ByteBloc works, a conversation with sales is familiar. For an ED director who wants the monthly line item before the next medical-staff meeting, it is an extra week you do not have.

That gap is not a character judgment. A company that also sells database performance software and web surveys can keep pricing off the public web and still run a durable product. It just means you cannot compare a quote you have not been given to a published $49.99.²

The rules model

ByteBloc’s published structural limits are real: up to 15 shift-relationship models, and a four-level shift preference scale of Prefer, Desire, Dislike, and Conflicts.¹ For hundreds of groups, that ceiling never mattered. The model was built by an emergency physician and refined across more than three decades of ED calendars. Fifteen relationship models is a lot of history.

It is still a ceiling. If the sixteenth relationship is how your dual-site nocturnists actually work, or if “dislike” is not enough nuance for a provider who will take weekends but not holidays, you either compress the rule or you write around it.

Slipstream ER does not try to clone that preference ladder. It treats rest-after-nights, approved time off, shift restrictions, and contract limits as hard constraints, then balances nights, weekends, and holidays with a fairness ledger that carries across months. The point is not that one model is wiser. The point is that one publishes a relationship cap and the other publishes a running equity score. Pick the one that matches the argument your group actually has.

Getting data in and out

ByteBloc’s documented import and export path is narrow: a user-list upload, a payroll custom export, an iCal calendar feed, and one vendor-specific CEP America integration.¹ There is no public API. There is no documented EHR or EMR integration. The AVIA Marketplace listing returns “None provided” for EHR integrations.⁵

Slipstream ER is not an EHR either. It does not talk to Epic. What it does have is a direct path in from the other schedulers groups already use: QGenda, Lightning Bolt, and CSV. If you are leaving an enterprise suite, that import is the whole product. If you are leaving ByteBloc, be honest about the next sentence: there is no ByteBloc importer. You export a CSV of the current schedule and provider list, then rebuild the rules. That rebuild takes minutes, not a services engagement, because the rule set is small on purpose.

Payroll is the other edge. ByteBloc’s support for categories and rate variations is a genuine strength generic tools lack. Slipstream ER does not do payroll. If the reason you open the product is hours-by-rate for the next check run, stay where that work already lives.

Public review is thin, and that is part of the record rather than a verdict. As of August 2026 ByteBloc has no G2, Capterra, or Software Advice listing. The only public user reviews are app-store ratings: iOS 3.1/5 from 7 ratings, and Android 3.7/5 from 7 reviews with 1,000+ downloads.³⁴ The 2016 apps have drawn complaints, dated 2022–2023, about slow data loading and thinner mobile value than the web app. Those notes are dated. The Android app was updated in April 2026, so they should not be written as a claim that the app is slow today. The two most recent iOS reviews, from January 2024 and October 2025, are five stars.³

When ByteBloc is the better choice

Buy ByteBloc if it matches the department you already run. These are not consolation prizes. They are the cases where a 2026 ED scheduler is the wrong bet.

• Your ByteBloc rule set is already dialed in. Fifteen years of shift relationships, preferences, and swap habits is expensive to recode for a cheaper monthly line. A working calendar is not a migration project until it hurts.
• You need its payroll rate-variation handling. Categories and rate variations are not a side feature for groups that close the books from the schedule. Slipstream ER will not do that work.
• You want three decades of EM-only track record and no interest in being anyone’s startup bet. ByteBloc has scheduled emergency providers since 1989. Its customers have stayed put for decades. That is a real operational preference, not nostalgia.¹
• You already coordinate 20–40 providers across sites the way their showcased customers do, and that multi-location setup is working. Switching tools to get a published price is a poor trade if the sites already agree.

ByteBloc’s genuine strengths are the ones the public record supports: 35-plus years of emergency-medicine domain knowledge baked into the shift-relationship model, payroll handling that generic tools lack, multi-site coordination, and a customer base that has stayed.¹ If those sentences describe the problem you walked in with, stop shopping for a newer calendar.

Switching from ByteBloc

There is no direct ByteBloc importer. Say that first so nobody starts a trial expecting a magic upload. The path is a CSV export of your current schedule and provider list, then rebuilding the rules in Slipstream ER.

That rebuild is not a services engagement. Shift types, rest rules, contracts, and opening fairness balances take minutes to confirm, not a statement of work. You can, and should, run a month in parallel. ByteBloc stays the system of record. Slipstream ER builds the next month beside it. You compare coverage, rest, and who drew nights before anyone is asked to leave the swap-meet board they already know.

1. Export from ByteBloc. Pull the provider list and the current schedule the same way you would for a payroll or backup export.
2. Import as CSV. Slipstream ER will take the roster. It will not silently translate 15 relationship models. You will set the equivalent hard constraints yourself, which is the honest part of the move.
3. Confirm rest, time off, and contracts. Rest-after-nights, approved absences, run-length limits, and monthly caps are hard constraints here. Enter any opening fairness balances you care about. History does not invent itself.
4. Generate next month in parallel. Keep ByteBloc live. Look at coverage, night and weekend distribution, and the names that used to absorb every holiday. If the draft is worse, you still have ByteBloc. If it is better, you have a month of evidence.

Apps, iCal feeds, and swap workflows exist on both sides of this comparison. They are not the reason to switch. The first question is whether a published-price engine can cover your board with your real contracts. Everything else is downstream.

Try it next to the month you already trust

A fair comparison is not a slogan. Export the roster ByteBloc already holds, set the rules your group already argues about, and generate the month you are about to publish. Thirty days. Up to 50 providers. No credit card.

If ByteBloc is still the better fit after that month, you will know why: payroll rates, a 15-year rule set, or a vendor you do not want to re-underwrite. If it is not, you will have a schedule instead of another demo.