Resources

Practical engineering resources

Guides, checklists and playbooks on the decisions that are expensive to get wrong. Everything here is a real piece of writing rather than a download gate.

No gate: Nothing here asks for an email before you can read it
Requests: Suggest a topic for the library

Library

Browse by format

4 min readWhat PCI DSS actually requires of a small merchantPCI DSS scope is decided by how card data flows through your systems, not by your size. Here is what changes when the card never touches your servers.
4 min readEMV, tokenization and 3D Secure explained properlyThree payment security mechanisms that get confused with each other. What each one actually does, where it applies, and what it protects you from.
4 min readPayment orchestration: when it is worth it and when it is notRouting payments across several processors solves real problems at scale and creates real complexity below it. How to tell which side you are on.
4 min readHow to tell whether a task is an AI problemFour questions that separate work worth evaluating with a model from work that belongs in ordinary code.
4 min readRetrieval over your own documents: what decides qualityMost retrieval systems fail on chunking, metadata and permissions rather than on the model. What to get right before choosing anything else.
4 min readBuild versus buy: the questions that decide itMost build versus buy debates go wrong by comparing a licence fee to a project cost. The real comparison is different.
4 min readIdempotency: the idea that prevents duplicate everythingA lost response can turn a reasonable retry into a duplicate order, email or charge. Idempotency helps, but its boundary must include the actual effect.
4 min readWhen to use an orchestrator and when to write codeA workflow tool and a service solve the same problems differently. Four criteria that settle which one a specific process needs.
4 min readDeciding which system owns which fieldA sync cannot resolve conflicting business rules on its own. Decide who can write each field before connecting the systems.
4 min readIntegrating with a system that has no APIExports, database replicas and file exchange are all workable. Screen scraping usually is not, and here is how to tell the difference.
4 min readWebhooks done properlyReceiving webhooks is easy. Receiving them so that duplicates, replays, out of order delivery and outages do not corrupt your data takes six specific things.
4 min readBuilding an API other people will useAn internal API that becomes a partner API exposes every undocumented assumption. What to settle before the first external caller.
4 min readFixed scope is a feature, not a constraintAgreeing exactly what gets built before building it protects the client more than the supplier. What a written scope actually contains.
4 min readTesting what matters rather than chasing coverageA coverage percentage tells you almost nothing. Ranking behaviour by what a failure would cost tells you where to spend.
4 min readPerformance budgets, and why averages lieA page that is fast on a development machine with fifty records tells you nothing. Set the budget first and measure against real conditions.
4 min readAccessibility as an engineering requirementDefine accessibility behaviour while components are designed, then verify it in the complete workflow. Automated checks are only part of that evidence.
4 min readWhy the database should refuse invalid dataApplication validation holds only for the paths someone remembered. A constraint holds for every path, including the import script written at midnight.
4 min readEvaluating an AI feature before it shipsWithout a fixed set of real cases, the only available verdict on a prompt change is that it seems better. Here is how to build one that is worth trusting.
4 min readTaking deposits and charging a balance laterA deposit now and a balance in six weeks touches holds, saved payment methods, authentication rules and cancellation policy. Here is the whole flow.
4 min readA dispatch board that understands the job, not just the calendarModel skills, travel, parts and job state before letting a dispatch board assign technicians. A free rectangle is not proof that a visit is feasible.
4 min readEquipment history that survives a technician changeConnect sites, installed equipment and service visits without turning every note into an unsearchable customer timeline.
4 min readArrival windows that do not promise an impossible dayOffer home-service appointment windows from real capacity, then keep confirmation, estimates and changes distinct in the customer experience.
4 min readOffline job notes without losing office changesDesign a technician workflow that preserves field observations during a connection loss while keeping assignment and approval decisions authoritative.
4 min readService request forms that give dispatch useful informationAsk for enough context to route a home-service request without turning the first contact into a diagnostic questionnaire or a false booking confirmation.
4 min readTurning a cleaning contract into versioned site checklistsTranslate a site scope into daily and periodic work without losing the agreement behind each task or rewriting the history of completed visits.
4 min readCleaning attendance exceptions without false proofUse check-in signals to find uncovered shifts while recognising the limits of location, shared devices and site codes.
4 min readClient cleaning reports that explain exceptionsBuild a client portal around completed work, unresolved exceptions and follow up actions instead of a wall of green checkmarks.
4 min readSite consumables replenishment without duplicate ordersConnect site counts, approved replenishment and delivery receipts while keeping requested, ordered and available stock separate.
4 min readBoarding capacity is more than a count of kennelsRepresent suitable spaces, overlapping stays, household sharing and review requirements before confirming a boarding reservation.
4 min readGrooming schedules that learn from the work recordUse reviewed service history and explicit resource rules to estimate grooming appointments without treating breed alone as a reliable duration.
4 min readRecurring dog walks with exceptions that do not duplicateSeparate a standing walking arrangement from each visit so holidays, cover and one-off changes do not corrupt the next week of work.
4 min readPet service packages with an explainable session balanceTrack prepaid entitlements through bookings, attendance, cancellations and corrections without treating one editable balance as the entire record.
4 min readHousehold permissions for pet booking portalsSeparate booking, payment, pet information and pickup permissions instead of assuming everyone linked to a household has the same authority.
4 min readDaycare and boarding reports built during the shiftCapture useful observations as care work happens, then review what is shared with the household without turning photos into the only record.
4 min readWhat owning your software actually meansOwnership is four separate things, and a supplier can give you some of them while keeping the ones that matter. Here is the checklist.
4 min readThe handover package: a checklistWhat a complete software handover contains, and the test that tells you whether it is real.
4 min readWhat to ask a software supplier before signingTwelve questions that reveal more than a portfolio. The answers tell you what happens when the relationship ends.
4 min readReviewed cleaning hours from rota to payroll exportKeep planned shifts, attendance events, approved hours and exported records distinct so corrections remain traceable across the payroll handoff.
4 min readHow to handle chargebacks in softwareA dispute is a workflow with a deadline, not an email. What to build so evidence is assembled automatically and nothing expires unanswered.
4 min readAutomations that stop when the customer repliesThe most damaging automation failure is not a missed send. It is a sequence that keeps chasing someone who already answered.
4 min readWhere AI should hand over to a personThe handover is a design decision with commercial consequences. Getting it wrong in either direction is expensive.
4 min readReconciliation: the job that runs when nothing is wrongScheduled comparisons can find missing or inconsistent records even when no request reported an error.
4 min readVan stock and return visits need one parts workflowConnect part requests, reservations, van transfers and job consumption so a return visit is scheduled against more than an expected delivery date.
4 min readCleaning cover swaps that preserve site access rulesA replacement cleaner needs more than an empty shift. Model eligibility, access instructions, acceptance and handover as part of cover scheduling.

Let’s talk about the system you need.

Tell us where the current process breaks down. We can map the workflow, examine the integration requirements and define a practical scope for the build.

Discuss Your Project support@sawhorsesoftware.tech

A mutual NDA is signed before project details are shared.
Scope is fixed in writing before any build starts.
You own the source code, the IP and the documentation at delivery.
Support plans are available and tailored on a discovery or technical call.

Browse by format

Tell us what you need written

Let’s talk about the system you need.