How to Choose a Software Development Company: Six Criteria

Choosing a software development company is a decision about accountability rather than technology, because two firms can propose the same stack, timeline and price and still hand you different outcomes, depending on who owns your requirements, who owns your testing, and what happens when something changes in week six. This guide sets out how to choose a software development company against six criteria, and the question to ask on each.

It is written for you if you are commissioning software for a mid-market business without an in-house development team, so you will be judging people, not specifications. If the system you are buying is an ERP, your decision has a different shape, and Zoosh Digital covers the Microsoft Dynamics 365 Business Central version of it in how to choose a Business Central partner.

The six criteria, and the question that separates firms on each

Six things decide whether your software project lands, and on each of them one question tells you more than a proposal will, so put all six to every firm on your shortlist in writing.

Technology experience: what a portfolio proves, and what it does not

A portfolio proves that a company has delivered comparable work, but not that the people who delivered it are still there or will be assigned to you, so use it for your shortlist and then ask the two questions below.

Ask: which parts of this portfolio did the people on our proposal build?

A firm that can answer will name individuals and the parts each of them built, while a firm that cannot will move you back to company-level experience. Zoosh Digital's published guidance on choosing an ERP partner puts that risk in ERP terms, as "the most common root cause of ERP partner dissatisfaction is discovering after contract that the project is staffed by junior resources rather than the team present during the sales process". On a bespoke build you want the same three things: names, allocations and end dates.

Ask: can we speak to a client whose project did not go to plan?

One reference from a project that went wrong will teach you more than three from projects that went well, because you are learning how a company behaves when it is at fault. Ask what the acceptance test was and who signed it off, what happened in the weeks after launch when the first defects appeared, and whether the code could be handed to another firm.

How the work gets delivered, and which variable your contract lets move

Waterfall against agile is no longer your useful question, because what you need to know is which of time, cost and scope your contract lets move once your requirements turn out to be incomplete. The UK government's Contracting for Agile guidance note (Digital, Data and Technology Playbook, June 2023) puts the trade plainly: agile delivery "constrains the time and cost available for delivering the desired outcome(s)" so that "the scope becomes the variable", while in a waterfall project "time and cost can vary" instead. Neither model works for you if nobody writes down which of the three may move.

Ask: which of time, cost and scope does our contract make the variable?

You want a written change process, with a named decision-maker on each side, a cost and time impact stated before you accept a change, and a record of what you traded away for it. If S, M, L and XL sizing is offered to you as a firm's own method, it is an industry convention. The same guidance goes further, suggesting that you award "multiple contracts (to different providers) each of which is for a 'discovery stage'" and then proceed "to a longer-term contract only with the provider whose solution has demonstrated that it is most likely to deliver the intended outcomes". If your project is an ERP implementation, the guide linked in the introduction takes the change-control version of this question further than this one does.

What the team actually includes, and what a thin team costs you later

What you are buying is a named set of roles, and this is where two quotes for the same project stop being comparable, because a lower price usually contains fewer roles and the missing ones become your job: your requirements, your priority order, your testing, your release. For a build of any substance you need a named owner for requirements, design, technical lead, development and testing, none necessarily full time.

Zoosh Digital's case study for GDPRWise (bespoke product development, not a Business Central project) lists that team as a product owner, a designer, a cloud architect, a lead developer and full stack developers, which gives you a shape to hold your own proposals against.

Ask: who owns requirements, and who owns testing?

If the answer to either is that they work closely with the client on it, then the answer is you, which can be right and is usually cheaper, but you want it decided in week one, not discovered in month three. Ask for each person's allocation as a percentage of their week, and for its end date.

How to compare quotes that are not like for like

Three quotes for the same software are rarely comparable, because each prices a different interpretation of what you asked for, so normalise your inputs first: the same one-page scope statement and the same written assumptions to every firm, then ask each where it disagrees.

Then read each quote for what it excludes, the blended day rate you get by dividing its price by its estimated effort, what it assumes about the state of your data, and what your second year costs once you count hosting, licences, support and keeping the software current. Read the section on the state of your data carefully, because Zoosh Digital's published experience of ERP projects is that "the businesses that hit their go-live date are almost always the ones that completed a thorough data assessment and fixed their scope in writing before the project started" (Business Central implementation timeline and best practices).

Why communication and change management decide whether anyone uses your software

Software that works and nobody uses is a failed project with a passing test suite, so what you are assessing is not how quickly a firm answers your email, but whether it has a method for changing how your people work. In Zoosh Digital's experience on mid-market projects, the line item a buyer has not costed is their own people's time, and its published guidance on ERP timelines and why projects run late puts the commitment for a named internal resource at 20 to 30% of their working time.

Bespoke projects are smaller than ERP implementations, but the principle holds for you, because if the person answering your weekly questions is also closing your month-end, your project waits. Ask what handover looks like as well, since the point of the whole exercise is that your own team can run the result afterwards without paying somebody to press the buttons.

Ask: what is the warranty period after acceptance, and what counts as a defect?

This decides who pays for the first months of your live system, and you need two answers you can hold a firm to: how long after sign-off it fixes faults at its own cost, and where the line sits between a defect and a new requirement. Get that definition into your contract, because without it every fault becomes a change request with a price. If you are buying an ERP implementation, support for the first six months is priced differently, and the guide linked in the introduction covers it.

What belongs in the contract: code ownership, data and exit

Commissioning software does not, by default, give you the copyright in it, so if you want to own what you paid for, you need a signed assignment and you need to read its carve-outs. Under section 11 of the UK Copyright, Designs and Patents Act 1988, "the author of a work is the first owner of any copyright in it". Section 23 of Ireland's Copyright and Related Rights Act 2000 works the same way, providing that "the author of a work shall be the first owner of the copyright unless" one of four exceptions applies, none of which is commissioning.

Both Acts require the assignment to be in writing, and they are worded differently, so each deserves its own quotation. Section 90(3) of the UK Act provides that "an assignment of copyright is not effective unless it is in writing signed by or on behalf of the assignor", while section 120(3) of the Irish Act provides that "an assignment of the copyright in a work, whether in whole or in part, is not effective unless it is in writing and signed by or on behalf of the assignor".

So your question is not whether a firm will assign the copyright, but whether the signed assignment is in your contract and what it leaves out, because a firm that reuses its own internal libraries will want to keep them, which is reasonable once you know which parts of your system you are licensing and not owning. What you own also depends on what you are buying, and Zoosh Digital builds bespoke software, extensions to Business Central and off-the-shelf Business Central implementations, so ask your shortlist which of the three they are proposing.

• Personal data. Where a firm will process personal data for you, Article 28(3) of the GDPR requires a contract covering the eight matters the Information Commissioner's Office lists, from documented instructions, confidentiality and security measures to sub-processors, data subjects' rights, assisting the controller, audits and inspections, and end-of-contract provisions. Read the sub-processor clause, where any offshore part of your project appears.
• Exit and portability. If your software will run as a hosted service, the EU Data Act (Regulation (EU) 2023/2854), applicable from 12 September 2025, sets a framework for customers to switch between providers of data processing services, so your contract should name your exit process, a usable data export, and what it will cost you.
• AI features. If your software will include AI functionality, the transparency rules in Article 50 of the EU AI Act started to apply on 2 August 2026, so name the party responsible for meeting them before you sign.

Red flags in a software development proposal

The red flag to check for first is a delivery team with no names in it, because you cannot hold a role to anything, only a person. Six to hold your shortlist against:

• No named delivery team, with roles written as functions and no individuals, allocations or end dates you can hold anybody to.
• References you cannot contact, named only as a sector rather than a company you could ring.
• No written change process, only an assurance that the firm will be flexible, which lasts until flexibility costs it money.
• No defined support window, with support described to you as available rather than specified, and no response times or price.
• No copyright assignment clause, or one that appears for the first time on the day you are asked to sign.
• A technology recommendation before anybody has asked how you work. Zoosh Digital's own sequence puts discovery and process mapping before design for this reason, and a firm that leads with technology is proposing what it likes building.

None of these is disqualifying on its own, but two or more in the same proposal have earned you a difficult conversation before you sign.

Where Zoosh Digital sits, and where it does not

Zoosh Digital is a Microsoft Dynamics 365 Business Central implementation and technology partner based in Ireland, helping mid-market organisations across the UK, Ireland and Europe design, build and run ERP and bespoke software systems that fit how their people actually work. It is senior-led rather than a large multinational, it works by co-creation, with discovery and process mapping before design, and it publishes 30+ design and technology experts, 50+ cloud propositions built and 40+ customers globally, with offices in Ireland, the United Kingdom and Hungary. It is a Microsoft partner, listed in Microsoft's partner directory for Dynamics 365, Azure and Power BI.

Its published position on building against buying is stated as follows: "Zoosh Digital's position on this is deliberately neutral, because Zoosh Digital builds bespoke software, builds Business Central extensions, and implements off-the-shelf Business Central. There is no single answer it is incentivised to sell." The same guidance on when building beats buying adds that, in Zoosh Digital's experience advising Irish and UK SMBs, a meaningful share of businesses that arrive expecting to commission a full custom system are better served by a Business Central configuration or a smaller extension. If you are weighing a first ERP, start with what Business Central is, and whether you are ready for ERP.

Where Zoosh Digital is not the right choice for you: if you want developers billed by the day and directed by your own project managers, you are describing a staffing arrangement and not an implementation partner, and a marketing website belongs with a digital agency.

FAQ

How much should a custom software project cost?

There is no defensible single figure for your project, because price follows your scope, your team composition and the state of your data, which is why Zoosh Digital's own guidance says plainly that "this article does not publish price bands, because any figure quoted without understanding your scope is just a guess" (bespoke software development). Zoosh Digital publishes duration instead, at 8 to 16 weeks for a simple internal tool, 10 to 20 weeks for a mid-complexity platform, and six to twelve months or more for a complex enterprise system, so place your project in the right band and price discovery before you price the build.

Should we choose a local or an offshore software development company?

Your decision turns on three things a day-rate comparison leaves out: your total cost including your own management time, which jurisdiction governs your contract and your personal data, and who is accountable to you when something breaks at 9am. Zoosh Digital makes the case for local delivery in custom software development in Ireland, made by an interested party, so test it against your own numbers.

What should be in the contract with a software development company?

You want a written scope with your assumptions stated in it, a change process with named decision-makers and a cost impact per change, a copyright assignment signed by the firm, a GDPR Article 28 processing agreement naming any sub-processors, an acceptance procedure saying who signs off for you, a warranty period defining a defect, and a support arrangement with response times and a price.

How do we check references properly?

Ask each referee what the acceptance test was on their project and who signed it off, what happened in the weeks after launch, and whether they could move the code to another firm. Those three answers tell you more than a testimonial does, because each one is checkable against a document.

Closing thought

A firm that welcomes your awkward questions is showing you how it will behave in month seven, when something is wrong and somebody has to say so. If you want to work through the six criteria against a specific project, Zoosh Digital's team is happy to have that conversation with you, including the version where the answer is that a bespoke build is not what your business needs.

Referenced sources

• GOV.UK. www.gov.uk/government/publications/the-digital-data-and-technology-playbook/contracting-for-agile-guidance-note-html.
• legislation.gov.uk. www.legislation.gov.uk/ukpga/1988/48/section/11.
• Irish Statute Book. www.irishstatutebook.ie/eli/2000/act/28/section/23/enacted/en/html.
• legislation.gov.uk. www.legislation.gov.uk/ukpga/1988/48/section/90.
• Irish Statute Book. www.irishstatutebook.ie/eli/2000/act/28/section/120/enacted/en/html.
• ICO. ico.org.uk/for-organisations/uk-gdpr-guidance-and-resources/accountability-and-governance/contracts-and-liabilities-between-controllers-and-processors-multi/what-needs-to-be-included-in-the-contract.
• European Commission. digital-strategy.ec.europa.eu/en/policies/data-act.
• European Commission. ai-act-service-desk.ec.europa.eu/en/ai-act/timeline/timeline-implementation-eu-ai-act.