If you’re in Los Angeles and take the 405 interstate south to the 5 south, you’ll come across a young child’s dream: Legoland.

Legoland is a family resort that’s based on a popular toy, legos. Legoland has stacks upon stacks of life-sized legos. Although most legos look like ordinary bricks, the magic is in how you stack and combine the bricks. Alone, they’re nothing special. But combined in the right way, legos can form some of the most beautiful and interesting works you’ve ever seen.

Much like legos, stacking and combining software can lead to wondrous results.

Tech startups run on different software stacks. It’s not just your company’s underlying technology infrastructure (LAMP vs. MEAN) but also the software that you use on a daily basis to make your company operate smoothly.

Business-to-business software is becoming increasingly fragmented. There are companies that build customer intelligence software, others build meeting room software, while even more make social media software. No one company has a solution that solves every single need of a company or department. Therefore startups are “stacking” different software solutions on top of one another to create a the perfect solution for their team.

For example, part of your team’s productivity software stack might include Trello for project management. But are you include products like Roomzilla for meeting room software and Boomerang for scheduling personal emails? They too play a pivotal role in your team’s productivity. It’s really up to your team to determine what tools you need and can afford to create the perfect software stack.

Here’s a list of must-have software for startups based on software we currently use and have used in the past.

HelpScout

HelpScout is a great tool to help your team with its customer service experience. It can automate tasks, keep your support team on the same page, and even has a knowledge base feature that potential customers can reference when they have a question.

Alternatives to HelpScout: Zendesk, Groove, HappyFox

Slack

Slack was one of the fastest growing companies in tech last year. This internal communication tool keeps teams in the loop, eliminates unnecessary email, and offers fantastic search.

Alternatives to Slack: Hipchat, Flowdock, Gchat

Boomerang

Boomerang for Gmail lets you schedule to send an email later or schedule a follow up reminder. It’s an easy plugin to your existing Gmail account. We love using this for the sake of sales email followups.

Alternatives to Boomerang for Gmail: LetterMeLater, Followupthen, Followup.cc

Roomzilla

Roomzilla is easy-to-use meeting room software. You might not know it, but your startup needs a conference reservation system to make your conference room function smoothly. Roomzilla helps by pulling in a central calendar system that is easily accessible via your computer or tablet. Team members can check when conference rooms are available and book them when they’re free.

Alternatives to Roomzilla: Yarooms, Robin, Eventboard

Olark 

If your business needs to answer customer questions fast, Olark is the tool for you. Olark has great live chat features to quickly help a potential customer with pressing questions before they decide to make a purchase.

Alternatives to Olark: Intercom, Desk, Velaro

Kissmetrics

Analytics software can tell you what’s happening on your website, helping you to improve and optimize conversion rates. Getting a better understanding of who is visiting your site and what they do on your site before making a purchase is invaluable information.

Alternatives to Kissmetrics: Mixpanel, Hotjar, Track.io

Google Analytics

The godfather of web analytics, Google Analytics is free and offers great features to any business. Know how many people are coming to your site, which sites are sending you traffic, track campaign performance, and analyze user behavior on your site.

Alternatives to Google Analytics: Clickly, StatCounter, Chartbeat

Appcues

Getting a customer to sign up for a free trial is a big deal. But if they don’t stick around to pay when the trial is done, then something is wrong. Appcues helps onboard new users and also helps retain them as a customer in the long-run.

Alternatives to Appcues: Hopscotch, Autosend, Tour My App

SproutSocial

SproutSocial is a social media dashboard to help your team publish and respond to social media mentions faster. Plan out your tweets and Facebook posts, and know the history of your conversations with a particular user.

Alternatives to SproutSocial: Hootsuite, Buffer, Market Me

Wistia

If your company uses video, Wistia is a great option for hosting and analytics. Unlike YouTube that just tells you when your video has been seen, Wistia will tell you how far they’ve watched, when they’ve paused, along with other valuable insights.

Alternatives to Wistia: Vidyard, PersoniCom, SundaySky

Hubspot

Hubspot is an all-in-one inbound marketing automation software suite. It can help with everything from email marketing, SEO, social media, landing pages, and more.

Alternatives to Hubspot: Marketo, InfusionSoft, Act-On Software

Optimizely

A/B test your website’s copy, button placement, and more with Optimizely. Know what’s working and what’s causing your visitors to bounce by setting up A/B tests with Optimizely’s drag and drop software.

Alternatives to Optimizely: Visual Website Optimizer, ClickThroo, Convert

Mailchimp

Capture emails and send newsletters, drip campaigns, and welcome emails with Mailchimp. You can create beautifully designed HTML templates to reuse or send simple text only email campaigns.

Alternatives to Mailchimp: Get Response, Campaign Monitor, Vertical Response, Constant Contact

Trello

Keep your team on the same page with a project management tool like Trello. It’s simple, visual, and let’s you know where your team is with a project.

Alternatives to Trello: Asana, Wrike, Basecamp

Simply Measured

Get detailed social media analytics and know which social channels are working for you. Go beyond the “like” or “follower” to get actionable social insights.

Alternatives to Simply Measured: Sysomos, Netbase, Sprinkr

Unbounce

Unbounce allows you to easily set up landing pages for your business, with no programming or design skill necessary. Their drag and drop interface makes setting up a landing page with your email marketing solution a breeze.

Alternatives to Unbounce: Kickoff Labs, Instapage, Leadpages

There are literally thousands of software products on the market today for startups to choose from. Some verticals have dozens of competitors (email marketing software), while others have few (meeting room software). Therefore it’s important for you to do your due diligence.

First determine what your team’s needs are (short-term and long-term) and then start to brainstorm what your software stack will look like. If you’re looking for more examples, here’s a site that has some of the top tech companies’ software stacks. This includes application/data, utilities, DevOps, and business tools. Here’s another one that just has marketing stacks.

The journey to your ideal software stack might mirror your startup’s growth, little-by-little. But you’ll eventually find out the best stack for your startup to run effectively and efficiently.