How to write an SRD (Software Requirements Document) for startups?
SRD stands for Software Requirements Document. Yet, the topic of documentation in fast-paced digital startups can seem like a burdensome task.
During the waterfall methodology, documentation indeed was a bit excessive. As Agile evolved to offer rapid development cycles, documentation lost its priority. There was a point when documentation like an SRD was almost an afterthought. After all, there were nifty emails where more and more people are being CC’d, as well as Excel spreadsheets.
However, documentation has gained its positions back. It happened all due to the amount of confusion, rework, and scope creep. All of which were caused by problematic requirements and had a depleting effect on businesses. And there are statistics to prove it.
But documentation is not anything like in the days of waterfall methodology. Agile documentation has an evolving nature and is not set in stone.
In this blog post, we’ll provide a comprehensive guide on how to create a Software Requirements Document that will benefit your startup.
Table of contents
Why is writing an SRD for your startup vital?
Research group InfoTech has research data to prove how important writing down requirements properly is:
“Up to 50% of project rework is attributable to problems with requirements.
Of projects that fail, 70% fail due to poor requirements. ”
This problem is most valid for startups. After all, startups start small. The initial team might have a few people on it. Thus, things seem manageable with emails and Excel spreadsheets. Startups are quite dynamic, so things move quickly. As such, no time to reevaluate priorities. Thus, things seem to be working as is and time is not on the side of documentation.
And then there is always this piece of wisdom “If it ain’t broken, don’t fix it.”
However, when it does get broken, the bill is huge. It can either cost you everything (70% of the time) or just a lot (50% of the time).
To illustrate, even NASA lost $125 million because of problems with requirements. They had different teams interpreting measurements in different ways. One team interpreted numbers according to the English (or Imperial) units. The other team used the Metric (or International) system.
And this example is actually why they lost the Mars Climate Orbiter. So, they did fall within the 70%-fail with that project. And even hit the headlines with a sarcastic cartoon illustration shown below.
So, noting down requirements diligently is important.
This example is also important because it emphasizes the technical nature of a Software Requirements Document. Startups need a few documents to successfully launch. An SRD is the most technical of them.
What is a Software Requirements Document?
If you were building a house, an SRD is like floor plans, structural drawings, and electric schematics combined. To put it plainly, it is a technical description with metrics and specifications of your software product. Moreover, it also factors in the environment like different browsers, operating systems, devices.
An SRD is the most important document for tech leads, developers, testers, and other stakeholders like project managers and business analysts.
This document is also the basis for budgeting and setting timelines. A Software Requirement Document defines the project’s scope.
Tracking Changes
It is worth noting that the title page must have fields for revisions, reviews, and approvals. An SRD is created once but it can be updated every sprint. If the sprint lasts 1 week, then an SRD can change every week. So, the team must keep track of changes for accountability.
How to write an SRD?
There is a standardized outline for writing a Software Requirement Document. However, it is not rigid and can vary. Though, it is highly recommended to use a template. Especially if you Develop Custom iOS app or Develop Custom Android app as it helps to streamline the documentation process and ensure you tick all the important boxes.
An outline for an SRD
- Introduction – information about your app’s purpose, its intended use, and its audience. Also, project scope.
- Stakeholders and Roles – identify key roles in the project and their responsibilities. In startups, some people may have too many responsibilities, or some responsibilities may overlap. This section may be absent from some templates. However, it can set clear boundaries and prevent clashes and conflicts.
- Functional Requirements – description of major features. Here, a business analyst or project manager might also add detail about the intended use. It is often done via user stories along with acceptance criteria.
- Non-functional Requirements – description of requirements to the entire system rather than a feature. You can have here from 5 to 10 points depending on which template you deem necessary. The simple set includes:
- Capacity – how many concurrent users can use your software at once, performance metrics like page load times,
- Scalability – how system resources can be stretched (10x more users?) and still work as intended,
- Security – data privacy and data protection regulation,
- Ease of use – how responsive and intuitive the use of your software is, might include conformity to accessibility standards like WCAG 2.1.
- Reliability.
- System Architecture – the diagram of your architectural solution. It should include core functionality and the selected technology.
- Data Requirements – includes details on data storage, data schemas, and data security.
- User Interface Requirements – contains mockups, wireframes, color palettes, screen layouts, and style guides.
- Definitions and Acronyms – this bit can be placed after the introduction or at the end. It should contain all key terminology and acronyms.
Comprehensive Overview of Each Section of an SRD
At this point, it is clear that an SRD is an essential Startup requirement document. It guides all development processes. In addition, it details all requirements that put limitations and boundaries on your codebase. These are regulatory requirements, data management constraints, style guides, selected patterns, etc.
Introduction
In every startup, the team is growing during the development process. Some specialists start at the beginning of the project, some join in later. Testers are those who often appear later on the project. The problem of testing software without any context is quite pressing. Without a clear understanding of the app’s goal, testers can create gaps in test coverage. Or miss important test scenarios.
Well-written introduction section creates and maintains a shared understanding. It helps to overcome barriers when people join at different stages. However, it is more important that with a clear understanding, each specialist can contribute more to the project.
Section includes:
- Project overview;
- App’s goal and key functionality;
- Target audience and problems-to-solve;
- Intended use.
Stakeholders and Roles
When you explicitly assign areas of responsibility, people just tend to do their job better. Also, it leads to increased productivity. Employees start to better prioritize tasks and perform high-impact tasks first.
In addition, when you just start out, you might have only a few people. Their responsibilities will be expansive but easy to know who does what. When you add more team members, confusion will set in. To prevent it, this section is essential.
Section includes:
- Role;
- Employee name;
- Responsibilities;
- Communication channels and frequency.
Functional Requirements
Functional requirements describe each functionality in plain and concise language. Often, they are formed into a table according to their priority. Then, user stories and acceptance criteria follow. It allows the team to know:
- What functionality to complete first;
- Expected inputs/outputs;
- The behavior of the feature from the user’s perspective;
- Criteria the feature should meet including system response to unexpected inputs, incorrect inputs, and erroneous actions.
For example, here is an example of the Etsy data flow across system layers as it relates to reviews functionality. And such diagrams can be given for each functionality. They are still abstracted and do not include all details. But imagine that there is one developer working on UI layer; another person working on business logic and backend layer. And there is yet another person handling data storage. Having an agreed flow for implementing one functionality is quite handy. Even if you have a team of full-stack developers who implement a particular functionality end-to-end, they still need to follow similar patterns so that they don’t double up on internal modules and such.
This section is the main section for determining the scope of works and deadlines.
Non-functional Requirements
In an SRD, they define the quality of software. This section includes metrics on usability, industry regulation, performance constraints, and standards.
- What is your product’s take on accessibility?
- Do you need a high-availability system? If so, there is often a trade-off. As such, your team will have to make your system fault-tolerant.
- In contrast, if you might go for precision and architecture choices will include strictly typed languages and SQL databases. In that case, you’ll need extra testing and optimizations.
As such, non-functional requirements also impact the scope of your project. This section also helps your team to make the right decision. After all, each technical implementation has its trade-offs. Having looked at usability and performance metrics, it becomes clear what choice is right specifically for your startup.
For example, if you Develop Custom iOS app focused on e-commerce, some of the metrics mentioned in a Software Requirement Document can be:
- Usability:
- Percent of users who successfully make a purchase;
- Time it takes a user to make a purchase;
- Error rate such as errors users experience when filling out forms. You can also include here navigation errors, where users are sent to pages they didn’t intend to go to.
- Accessibility:
- What are your compliance levels with WCAG – A, AA, AAA?
- You can measure color contrasts for different elements. The requirements differ for regular text versus heading text, and such.
- Is your app screen-reader compatible?
- Performance:
- average screen load time;
- App launch time;
- Time to interactive;
- Crash rate;
- Battery consumption rate;
- Add-to-cart latency;
- Crash rate.
These are just some quality metrics for your software. The list can vary depending on the need of your project.
System Architecture
It describes key system elements and the interactions between them. This section often includes a schematic of the project’s solution. This is a high-level view of the entire system. It is likely that each person will be working only on one of the system’s components. However, it is crucial to understand the overall flow within the app. In addition, there are likely to be mentioned dependencies, cloud file storage, and other connected third-party services.
Data Requirements
The main point of data requirements is to have data models or Entity-Relationship Diagrams (ERDs). They would include:
- what data is stored,
- its data type,
- constraints,
- update and delete behavior,
- relational tables.
In addition, procedures for data retrieval, storage, and processing should be included. Especially, when it comes down to handling sensitive data like user’s personal data and payment information.
User Interface Requirements
These are mockups and wireframes. They give a general idea to the development team of main interfaces. There is no need to include revised final designs. They just should give all participants of the development process an idea about the appearance of the product.
In addition, there can be user journey descriptions and an additional mention of accessibility specifications.
Definitions and Acronyms
Any Software Requirement Document is likely to use quite a few terms and abbreviations. Does PM stand for a product manager or a product owner? Also, you might come across industry-specific definitions like SKU or GDPR. Not every person might have knowledge that SKU is a Stock Keeping Unit. Or that GDPR means General Data Protection Regulations.
In addition, there might be terms that are brand-specific or refer to internal culture. Most importantly though is to have a thorough description of the technical metrics and key performance indicators.
Other
As it was mentioned, the structure is not set in stone. Your project might have an SRD with fewer or more sections. For instance, you can include the Testing and Validation Requirements section. You might choose not to include the Stakeholders section. A Software Requirement Document is a vital part. Yet being a part of agile methodology – you can adapt it to the needs of your project.
Final Thoughts
If you have limited resources to devote to writing documentation, choose to write an SRD. This is a technical document that your team will use on a daily basis. Especially as your team grows, this document will save you a lot of money and project time which otherwise would have been wasted on unnecessary communication, rework, and interpersonal squabble.
FAQ: Writing an SRD for Startups
An SRD is a technical document that outlines the requirements, architecture, and specifications of a software product, acting as a blueprint for development and testing.
An SRD helps startups prevent scope creep, reduce rework, improve team communication, and ensure clear project goals, saving time and resources.
Key sections include: Introduction, Stakeholders and Roles, Functional and Non-functional Requirements, System Architecture, Data Requirements, User Interface Requirements, and Definitions and Acronyms.
In Agile, an SRD evolves with the project and is updated regularly, while in Waterfall, it is often a rigid document created at the project’s start.
Many believe SRDs are time-consuming or unnecessary for small teams. However, even startups benefit from a concise SRD to maintain focus, avoid miscommunication, and streamline growth.
Using templates and starting with essential sections like goals, key features, and basic architecture can simplify the process, with updates made as the project evolves.
