4xxi builds AI products on your own trusted content: systems that cite the exact source for every answer and say "no answer" instead of guessing. We work with legal, financial and education organizations, where a wrong answer has a real cost.
Our anchor project is AAAi ChatBook for the American Arbitration Association, launched in January 2025: a free public tool that answers questions about arbitration from AAA's own publications and rules. The language model only assists search and never writes the final answer, so every response links to its source or honestly reports that the data is insufficient.
How to start working with us: - Grounded AI audit: 2 weeks, $5–10k. Accuracy measured on your own data and a concrete plan, or 100% of the fee back. The full fee is credited toward a project signed within 60 days. - Prototype sprint: a deployable prototype in 5 business days, $20k fixed. - Ongoing engineering: senior-only team, billed hourly.
Why 4xxi: - A small senior team working together since 2008, founded by a scientist. - Kickoff within 3 business days of signing. - Clients stay with us for 5+ years on average; our longest relationship is over 12 years. - Our clients have raised $500M+. - We build our own AI products too, including edtek.ai, our grounded AI platform for legal teams and publishers.
4xxi offers competitive pricing, with project costs ranging from $17,250 to over $240,000 depending on scope. Clients highlight their exceptional value for cost, with many noting significant savings compared to onshore alternatives. Their commitment to quality and timely delivery enhances their overall value proposition.
4xxi has demonstrated capability across various sectors, including finance, education, and technology. This broad expertise allows them to tailor solutions effectively to different business needs.
Challenges with Project Management Turnover
One client reported initial difficulties with project management turnover, which caused challenges until the right fit was found. Since then, the project management has been stable and effective.
Commitment to Client Success
Reviews highlight 4xxi's dedication to client projects. Their commitment is evident in their drive to understand client needs thoroughly and their enthusiasm for delivering high-quality products.
Strong Project Management Skills
Clients commend 4xxi for their effective project management, marked by excellent communication, timely deliveries, and minimal oversight required from clients. This has contributed to a positive working relationship and successful project outcomes.
Innovative and Proactive Approach
4xxi stands out for their initiative in providing valuable input and creative solutions. Clients appreciate their willingness to suggest improvements and new ideas, adding value beyond mere execution of tasks.
Responsive and Available Team
4xxi is noted for their responsiveness and availability, making communication smooth and effective. Clients feel supported and valued, with the team consistently available to address concerns and provide updates.
“It’s been a really good relationship so far, and we consider them partners.”
Aug 23, 2017
Manager of Digital Projects, Smart School
Konstantin Seregin
Verified
Education
Irkutsk, Russia
Phone Interview
Verified
4xxi used Scrum methodology to map out and design an e-learning website which they are currently developing.
4xxi’s dual expertise in both the educational and IT fields have proven to be beneficial throughout this ongoing project. The uniqueness of the website concept has garnered unanimous positive feedback, and their team continues to leave a lasting impression by remaining confident and timely.
A Clutch analyst personally interviewed this
client over the phone. Below is an edited
transcript.
BACKGROUND
Introduce your business and what you do there.
I am the manager of digital projects at the Smart School Center for Educational System Design. We are currently designing an educational system, creating educational learning content, and training teachers for a complex in Irkutsk, Russia. My role is to develop their information infrastructure.
OPPORTUNITY / CHALLENGE
What challenge were you trying to address with 4xxi?
An important part of our business is to have project based learning, so we needed to have a special online web system for managing projects. We know there are some types of project management systems for adults, but they’re not educational, and we needed to design and build a system that would focus on that area. The system will include assessments of how students complete their projects as well.
SOLUTION
What was the scope of their involvement?
4xxi mapped out the concept to develop the website from scratch. They envisioned how it will work and focused on how it is solely for educational purposes and not project management. 4xxi has expertise in education, as well as technology and IT, so they were the co-authors and idea makers for this project. They’ve worked through a Scrum system while providing daily design updates for me, and both sides have been in constant contact regarding which aspects are good or what needs to be changed.
We just completed work on the description of what it will entail, and both sides agreed on it. Website development has begun, and they’re just starting to build the system. I like collaborating with them, and we are now discussing working together on an additional website.
What is the team dynamic?
There are 7 members of 4xxi’s team working on our project.
How did you come to work with 4xxi?
We heard about 4xxi’s COO because he is well known in the Russian educational field. We went to him due to his expertise in both education and IT, which ultimately led us to be so certain 4xxi was right for the project.
How much have you invested in them?
We’ve spent around ₽1,000,000 Russian Rubles [$17,250].
What is the status of this engagement?
We started working together in March 2017, and the relationship is ongoing.
RESULTS & FEEDBACK
What evidence can you share that demonstrates the impact of the engagement?
After showing the designs, ideas, and concepts to my colleagues, the feedback has been good. We’ve been told it’s unique and that we need to go ahead and create it.
How did 4xxi perform from a project management standpoint?
I’ve had the pleasure of talking to the managers and COO, and they’ve all been really good at communicating with us. They’ve also been on time with their deliverables thus far.
What did you find most impressive about them?
They have confidence in the IT, education, and financial area, which is impressive. It’s been a really good relationship so far, and we consider them partners.
Are there any areas they could improve?
I have no suggestions for improvement.
RATINGS
5.0
Quality
5.0
Service & Deliverables
Schedule
5.0
On time / deadlines
Cost
4.0
Value / within estimates
Willing to Refer
5.0
NPS
"I will recommend them to others.
HR Tool Development for Travel Industry Firm
Web Development
Confidential
Nov. 2016 - Ongoing
4.5
Quality
4.5
Schedule
4.5
Cost
4.5
Willing to Refer
4.0
“So far, new and complex features are delivered according to our specifications.”
Aug 14, 2017
Organizational Solutions Team, Travel Industry Firm
Anonymous
Verified
Hospitality & leisure
Germany
1,001-5,000 Employees
Online Review
Verified
4xxi augments an internal team in creating custom HR solutions, including a recruitment tool that streamlines the application process. 4xxi helps with both development and testing.
The recruitment tool has earned positive reviews from both applicants and recruiters, demonstrating the quality of 4xxi’s output. While there were a few synchronization issues, the team generally delivers within the deadline and project specifications.
The client submitted this review online.
BACKGROUND
Introduce your business and what you do there.
Our company operates in the travel sector, with 1,500 employees. We don’t use the traditional position nomenclature in our company. I am the responsible lead for a department called “organizational solutions.” We’re the technical support for the HR [human resources] department, building tools in-house as well as externally. My team takes care of delivering tools to the HR department, which be any kind of recruiting or HCM [human capital management] solution.
OPPORTUNITY / CHALLENGE
What challenge were you trying to address with 4xxi?
Within our company, we tried to tackle the recruiting process from a different perspective. We needed a tool that would help us recruit the best candidates without focusing on an applicant’s CV [curriculum vitae]. The target was to reduce the complexity of the application process, making it more appealing for candidates. For our recruiters, their aim was to find the best candidates as quickly as possible. None of the other tools on the market served our needs, which was why we decided to develop our own tool.
SOLUTION
What was the scope of their involvement?
4xxi has worked on an external-facing tool for recruitment. The story specifications and design mock-ups were provided before the project started. 4xxi was involved in both development and testing. They did a great deal of support for feature decisions. They also shared their knowledge about common practices and technologies.
What is the team dynamic?
We work with 5 people from their team.
How did you come to work with 4xxi?
I took over the project, so I wasn’t involved in the selection process. My company was happy with the work 4xxi had done before, so they suggested using them for our tool.
What is the status of this engagement?
We started working with them in November 2016, and the engagement is ongoing. The MVP [minimum viable product] was successfully delivered within 12 weeks, including testing. Further development is still ongoing.
RESULTS & FEEDBACK
What evidence can you share that demonstrates the impact of the engagement?
We have received feedback from applicants about the MVP. We don’t have any internal users, but the external ones have been happy with the design. It’s different from what they’ve experienced in most of the other companies they’ve applied to.
How did 4xxi perform from a project management standpoint?
4xxi consistently delivers within the agreed scope and timeframe. Everything is delivered on time, although the project’s very complex synchronization set-up led to a small delay.
Sometimes the distance makes collaboration with an external provider harder. Regular meetings via video help strengthen the collaboration. We interact with them daily via Slack. They respond quickly and always get to the point.
What did you find most impressive about them?
I’ve been very happy with 4xxi. They deliver on time. So far, new and complex features are delivered according to our specifications.
Are there any areas they could improve?
There are always improvement areas, and this goes both ways. There’s no chance of everything going perfectly when 2 companies are working together. It would be better to have regular meetings with the whole team, especially when tackling more difficult features.
RATINGS
4.5
Quality
4.5
Service & Deliverables
Schedule
4.5
On time / deadlines
Cost
4.5
Value / within estimates
Willing to Refer
4.0
NPS
Web Dev for Competition Website
Web Development
$10,000 to $49,999
Dec. - Jan. 2015
5.0
Quality
5.0
Schedule
5.0
Cost
5.0
Willing to Refer
5.0
“I haven’t given them a project yet that they couldn’t handle… they’ve always delivered.”
Aug 9, 2017
Founder, Circus Intersection
David Nadezhdin
Verified
Advertising & marketing
Montreal, Quebec
1-10 Employees
Online Review
Verified
4xxi used PHP and HTML5 to rapidly develop the front and backend of an application compatible for desktop, tablet, and mobile. This involved creation of a unique visual algorithm and server infrastructures.
4xxi remained highly communicative during this project to ensure delivery of time-sensitive software. Due to their expertise, dedication, and systematic approach, the application has received world recognition.
The client submitted this review online.
BACKGROUND
Introduce your business and what you do there.
I am the founder of Circus Intersection, and we bring together digital strategy and custom development for web, Facebook, and mobile applications.
OPPORTUNITY / CHALLENGE
What challenge were you trying to address with 4xxi?
We wanted to create a promotional site for the international competition Woolmark Prize. This involved a unique visual algorithm by which our users could create and promote derivative works based on 12 pieces by leading designers. The challenge was to launch the website in a very limited amount of time.
SOLUTION
What was the scope of their involvement?
We provided 4xxi the concept of the project, as well as the designs. We needed the front and backend of the website and server infrastructure, which included setup and support. Due to the limited time we had to do this, we had a lot of calls to finalize the scope.
The competition had international designers take pictures of their models and clothing. They wanted people to be able to manipulate that image and have every person re-manipulate either the original image or the next image down, then change it a bit more so that everyone could have an influence. You would be able to view the evolution and the timeline of that image as people applied different effects to the image itself.
Due to this, we had to have a different algorithm, because if there were too many people only focusing on one type of effect, then it could get boring. Therefore, we had an algorithm that loaded the most recent picture, but that was also based on the least, or most used effect so that you would actually get a good sense of what people were doing to the image. They were involved in helping us create that algorithm.
They handled the entire project after I gave them the specs and layout directions. I asked how we were going to build the website and launch it, because we needed to do it very quickly, and we knew they were going to have a big influx of traffic. They helped us with server infrastructure, and everything involved with delivery and optimization of the layout for desktop, tablet, and mobile. We were allowing people to play around with the images and manipulate them, so it was extremely important the site was functional on all platforms. They used PHP, HTML5, and a few different plugins.
The app needed to load quickly, so it had to be lightweight even though it was loading very heavy images. They had to really streamline the delivery of making sure the images that were going to be manipulated were being sent in different formats for various devices. The manipulation of the images that people were doing with their fingers or mouses would also have to be rendered on different resolutions as well, to ensure it would be visible across all platforms. We had an impossible timeline, but 4xxi made it happen.
What is the team dynamic?
There were 5 people working on the project.
How did you come to work with 4xxi?
I’ve been working with them for 15 years. I’ve known them for a long time.
How much have you invested with them?
We’ve spent between $10,000-$50,000 with them.
What is the status of the engagement?
The project began in December 2015 and was completed in 1 month. The project was delivered on time.
RESULTS & FEEDBACK
What evidence can you share that demonstrates the impact of the engagement?
They gave us another project, so the clients were very happy. The competition had a substantial amount of entries and Woolmark got some world recognition as a contest. It’s been an interesting approach because they got the community involved in participating with actual designers, as well as being a part of the entire process.
How did 4xxi perform from a project management standpoint?
We got weekly feedback and communicated daily through Skype, phone calls, and email. The project needed to be finished quickly, so if we needed anything from each other, the response was immediate and simple.
What did you find most impressive about them?
They’re a trained IT team, and they’re not just developers that learned on their own. They’re engineers and mathematicians. They learn how to do very high-end work with SAP protocols, and they have a very systematic approach to how they work.
Are there any areas they could improve?
I haven’t given them a project yet that they couldn’t handle. They’ve always delivered.
RATINGS
5.0
Quality
5.0
Service & Deliverables
Schedule
5.0
On time / deadlines
Cost
5.0
Value / within estimates
Willing to Refer
5.0
NPS
Showing 11-13 of
13 Reviews
Our Story
4xxi was founded by a scientist, and we still work like one: measure first, then build. Our engineers have worked together since 2008 and shipped 100+ products. We believe AI should earn trust, so our systems cite their sources and say "no answer" rather than guess. We stay small and senior on purpose, dive into each client's domain before writing code, and take responsibility for everything we ship. Several clients have stayed with us for over a decade.
Meet the Team
Evgeny SmirnovFounder and Lead AI Engineer
Founder and lead engineer of 4xxi, 20 years in software. Working with ML since 2012 and LLMs since 2022, he designed the grounded retrieval architecture behind AAAi ChatBook and Edtek. PhD in mathematics and physics, researching machine learning for
Egor TomilinArchitect and AI Developer
Egor joined 4xxi in 2014 as a back-end developer, led the engineering team, became CTO in 2017. He still designs and builds the systems he is responsible for, with 18 years in software development, from back ends and to AI applications.
Nigel HopkinsonDirector
Director of 4xxi since 2018. Previously CEO and VP of Sales at Intuit Services (Europe), SealedMedia and Office Shadow, leading them through one IPO and two acquisitions, then sales director for banking and insurance at SAS.
What Sets Us Apart
Grounded by design
Our AI systems answer only from your verified content, cite the exact source for every claim, and return "no answer" when the data is insufficient. This is how AAAi ChatBook works for the American Arbitration Association.
Fast start, fast prototypes
Kickoff within 3 business days of signing. A deployable prototype in 5 business days. A small senior team means no ramp-up and no handoffs between layers of management.
Low-risk first step
Start with a 2-week Grounded AI audit: accuracy measured on your own data and a concrete plan, or 100% of the fee back. The full fee is credited toward a project signed within 60 days.
Locations (1)
23 Leyborne Park, Kew Gardens, Richmond, Surrey, United KingdomRichmond, EnglandTW9 3HB
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