Takeaways from our first Q&A Session

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Marius SprengerApril 8, 2021

Last week, we hosted the very first Q&A session with our community. Already in the early days, when lemon.markets was nothing more than a vague idea by a few students without any actual product, getting regular feedback from our users was one of the most important principles for us. That obviously has not changed. I mean, how else are you going to build a product that everyone enjoys if not by constantly incorporating ideas/criticism/feedback by the people that are already using it? So, we sat down in our Berlin office and talked to our users on Zoom for an hour. About our current state, what is planned in the next weeks and the long-term, and about ideas and questions that our users might have. In this blog post, we want to summarize the things we talked about.

Title Card for the Article "Takeaways from our first Q&A Session"

lemon.markets Q&A Session

When we think about lemon.markets, we want it to stand for transparency, a user-centric product, safety and an overall great experience. We think that a big part of that is communicating what we are currently working on and how we want the product to look like in the future. Take a look at the table of contents to see what interests you or read through the whole article if you want to know it all ;)

When we think about lemon.markets, we want it to stand for transparency, a user-centric product, safety and an overall great experience. We think that a big part of that is communicating what we are currently working on and how we want the product to look like in the future. Take a look at the table of contents to see what interests you or read through the whole article if you want to know it all ;)

Current State

We launched the first prototype of our API last September, even though we knew that it was neither perfect nor bug free at the time. The idea behind that is easily explained: find out as early as possible how people want to interact with the API. Even though we quickly got to a point where we got more sign-ups and API requests than we could handle, the prototype nevertheless helped us in further developing the idea of lemon.markets. While it was initially planned as a simple interface to automate your trading strategies, the user feedback quickly helped us in adapting our business idea towards building a trading infrastructure that allows to build all kinds of products. In Q1 2021, we focused on bug fixing here and there, but quickly realised that this only takes away our valuable resources. So, in early March we made a rather tough decision to not spend any more time on the prototype, but instead start from scratch and build a clean and new service. This decision was facilitated by the fact that the lemon.markets team more than doubled in size in March: we are now 7 core people working on the product full time + additional freelancers for Frontend Development and DevOps. We already notice a significant change in our execution speed, and we are working hard on building the real product that we’ve envisioned for quite some time now.


Maybe the most interesting piece of information: we are planning to offer real-money trading by the end of this year. Right now, we are finalising our talks with a banking partner that will help us offer our product. In general, we are thinking about our “relaunch” as a 3-step process:

  1. Version 2 of our sandbox environment (#stable)
  2. Backtesting Feature
  3. Live Trading

In order to avoid a scenario where we again cannot meet the requirements of new user signups and increasing API usage, we decided to tackle the relaunch step-by-step. This means that we will do an onboarding process with badges of 10 people each. These badges of new users can then sign up on our new web app, start with the sandbox trading and subsequently move on to backtesting and live trading later. If the experience works for them and everything is fine, we move on to the next badge. For us, this process has two advantages: First, we can scale up our API step-by-step, and second, the onboarding process is way more personal, which is great for new users, as they have a contact person that shows them everything they need, but also great for us, as we can get direct feedback and suggestions for improvements that we can then implement for the new badges. As we want to give back to the community, there will probably be some kind of waiting list, but we have not fully decided on that, yet. However, we will get back to the community once that is settled :)

Community Questions

Obviously, a large part of our discussion was us answering questions by the community. Find a summary of all community questions below.

GIF related to Community Questions

What is part of the Sandbox Relaunch?

As we outlined in the roadmap, we are currently working on building the sandbox environment from scratch — again. This will result in a much more stable and reliable API that will be way more fun to use. Simultaneously, we are also relaunching our web app and documentation, along with a complete rebranding of lemon.markets. Everything should work, look and feel much sleeker once we are done. We will also make sure to map different use cases in our documentation, so that it really helps you with getting started and continuously using our API — no matter what your level of expertise is when it comes to programming. Please have a look at our current documentation to identify what is missing for you and fill out this short type form afterwards. Thanks :)

What is the business model for lemon.markets?

We decided that a subscription model is the best strategy to fit everyone’s needs. Specifically, this means that we will limit the API usage and create different subscription plans out of that. This allows you to use lemon.markets in exactly the way that is good for you and your trading strategy/application. It also means that you do not have to worry about the number of trades you are executing, but can focus on building a great product for yourself. There will be no hidden costs or a specific price per trade. You simply pay the monthly fee associated to your subscription plan.

We believe in the power of freedom and transparency when it comes to using an API and brokerage in general. Therefore, we are trying to make the first step towards a trustworthy and enjoyable product by being open about our business model. Besides your subscription fee, there will also be additional ways for us to generate revenue. We will communicate them transparently once we figured everything out with our banking partner and lawyers. These additional revenue streams will not influence you as a user in any way, but we still think that it is important to communicate how we as a company make money.

Is it required to develop a trading algorithm in order to use lemon.markets?

A very clear no. We are very diversified on the use cases. Anything that you think can be built with our API, can probably be built :D

However, in the new sandbox environment, you will have to create either a strategy or an application if you want to communicate with our API. The typical use cases for a strategy is obviously an automated trading algorithm. An application, however, can be all kinds of things. You want to build your own Robinhood? Go for it. All orders within your app are then placed through our API. You want to build a trading dashboard where you can conveniently monitor trends for your favorite stocks? No problem. You can get the market data through us. Once we relaunched our product, we will also give you specific examples for what you can actually do with us.

Will there be additional data APIs? For example for stock news or text-based information?

Our focus currently lies in providing a stable market data service and a flawless order execution. Therefore, we are not sure if we will be able to provide additional data APIs, especially not right now. However, we might integrate data from other third-party providers and aggregate it, so our users can easily access it. This is rather mid- or even long-term, though.

What’s your tech stack?

We use 2 programming languages for our backend: Node.js and Python. Node.js is primarily used for asynchronous matters: we have to deal with a lot of data from the stock exchange. This is where Node.js comes in handy. For Python, we use Django as a framework. Our frontend is developed with React. For deployment, we are on AWS, leveraging the flexibility of Kubernetes clusters, as well as a couple of different databases and streams.

How are you planning on integrating the community?

This is super important for us. Community participation is a clear priority for us and we want to make sure that everyone who wishes to contribute to lemon.markets can actually do so. In general, the equation behind it is very simple: the users want a cool product. We want to have constant feedback and engagement. Essentially, both things go into the same direction and can be achieved by working together with our users. We published a Python SDK a while ago, and are very grateful if you decide to contribute to that or build your own SDK for JavaScript, C#, R, or whatever language you like. Contact us with your ideas and we will figure something out. We are also trying to make the process of contributing to lemon.markets a bit more structured, so please reach out if you have any ideas on how to do that.

Do you have some kind of forum at the moment?

Right now, we are using Slack to let the community ask questions to us and other community members. However, we are thinking about relaunching the community experience in the upcoming months. Slack is currently very valuable, as we can get feedback fast and help our users in a straightforward manner, but it might be hard to maintain once the community is growing. We also do not like that Slack is a closed system, as we do not want to exclude anybody. People that are interested in using lemon.markets should be able to connect with other users quickly and find information easily, which is why we are thinking about developing a more open system, where information is accessible for everyone. We might also go for a hybrid system with Slack and some kind of publicly available solution. We still have to make up our minds about what the best way to go is :)

We hope that you got a good insight into the work we are currently doing and the things we are planning for the future. We are super grateful for all of your patience, especially since there is no visible progress at the moment. But we hope that you got a feeling that there is a lot of stuff happening in the background, which will (hopefully) result in a product that everyone enjoys very soon. Do you have a question that we didn’t answer during the Q&A Session or do you have any additional suggestions for us? Feel free to comment below or write us an email at support@lemon.markets.

We are planning on making the Q&A sessions a regular thing, so please join our Slack community to not miss the next one.


your 🍋.markets team

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