Applied AI engineering studio · Sofia, EU

Applied AI, built to run.

We design, build and operate production AI and software for European businesses. Voice agents that speak Bulgarian and English, automations that log every step, data platforms that hold under load. You own the code.

Book a 30-minute call · See the work

• 9 practice areas
• BG + EN voice and text
• EU hosting by default
• 2024 founded in Sofia

Seven core practices. One way of working.

From a phone line that never goes unanswered to the database under your product. Each practice has a published pricing band and a clear list of what you receive. Two newer offers, agentic-coding enablement and AI search visibility with ChatGPT Ads, are on the practice areas page.

01 Internal Process Automation

The repetitive part of your team’s week, done by software that logs every step.

EUR 25–70k · 6-week initial engagement · Lead time: 4–6 weeks from signing, limited slots

02 Voice & Chat Agents

Every call and message answered, in Bulgarian and English, day and night.

EUR 3–12k setup · usage-based running cost · optional retainer · Lead time: 6–8 weeks from signing

03 Automated Lead Generation

Qualified conversations for your sales team, not lists.

EUR 30–90k · 8-week initial engagement · Lead time: 6–8 weeks from signing

04 Database Architecture & Operations

A data layer that stays fast, correct and recoverable under load.

EUR 20–60k · 6-week initial build · optional ops retainer · Lead time: 6–8 weeks from signing

05 Web Optimization & SEO

Faster pages, better rankings, and a site AI assistants can cite.

EUR 15–50k · 6-week initial engagement · Lead time: 4–6 weeks from signing, limited slots

06 Business Apps

The app your process actually needs, with the source code in your hands.

EUR 8–40k · 4–12 weeks depending on scope · Lead time: 6–8 weeks from signing

07 Custom AI Builds

AI built around your process, integrated natively, owned by you.

EUR 40–200k · 8–16 week engagement (scope-dependent) · Lead time: 6–8 weeks from signing

All practice areas

From real problem to running system, in five stages.

Every engagement follows the same order. Durations change with scope; the discipline does not. At the end of each stage you hold something concrete.

1. 01 Diagnose: Understand the real problem

   We sit with the people who do the work and map how it actually runs today: the documents, calls, systems and exceptions. Most projects go wrong at this point, so we do not rush it.

   You hold: A process map and a written problem statement

2. 02 Design: Agree what success means

   Before anything is built, we write down what the system must do, how we will test it, where the data lives and what it costs. You approve it or change it.

   You hold: Scope, acceptance criteria and a quote

3. 03 Build: Ship in two-week increments

   We build in short cycles. Each one ends with something you can use and review, so problems surface in week two, not in month four.

   You hold: Working software every two weeks

4. 04 Prove: Test before it meets customers

   AI systems are checked against a fixed set of real questions and cases. Automations first run in shadow, next to your team. It goes live when it passes, not when the calendar says so.

   You hold: Test results you can read

5. 05 Operate: Run it, then hand it over

   We deploy, watch the system under real use and fix what real use reveals. You receive the source code, the runbook and a support window. If you want us to keep running it, that is a retainer, not a lock-in.

   You hold: Source code, runbook and a support window

The same five stages run in every practice area.

Voice & Chat Agents

Hear how a call goes.

Our voice agents answer on a real phone line, in Bulgarian first and in English when the caller switches. They work from your own knowledge, use your calendar and systems, and hand over to a person when the conversation needs one. Below are two sample conversations, written to show the behaviour.

• Answers from your material

  If the answer is not in the source material, the agent says so instead of guessing.

• Bulgarian first

  Tuned pronunciation for Bulgarian names, streets and places. English when the caller switches.

• A person when needed

  Warm transfer to your team, with the context already captured.

• Every call on record

  Each conversation is transcribed and reviewable in your dashboard.

Sample conversation: Clinic reception: booking a first appointment

Bulgarian · inbound call · 19:40, after reception has closed

1. Agent: Добър вечер, свързахте се с рецепцията на клиниката. Аз съм виртуалният асистент. С какво мога да помогна? (Good evening, you have reached the clinic reception. I am the virtual assistant. How can I help?)
2. Caller: Здравейте, искам да запиша час при кардиолог. (Hello, I would like to book an appointment with a cardiologist.)
3. Agent: Разбира се. Първи преглед ли ще бъде, или контролен? (Of course. Will this be a first visit or a follow-up?)
4. Caller: Първи. (A first visit.)
5. System: Проверява графика на кардиолозите (Checks the cardiologists’ schedule)
6. Agent: Имам свободен час в сряда в девет и половина сутринта или в петък в два следобед. Кое ви е по-удобно? (I have a slot on Wednesday at half past nine in the morning, or on Friday at two in the afternoon. Which suits you better?)
7. Caller: Сряда сутрин. На името на Мария Петрова, телефонът е този, от който звъня. (Wednesday morning. The name is Maria Petrova, and the phone number is the one I am calling from.)
8. System: Записва часа · изпраща SMS потвърждение (Books the slot · sends an SMS confirmation)
9. Agent: Записах ви за сряда в девет и половина, първи кардиологичен преглед. Ще получите SMS с адреса. Ако имате направление, моля, носете го. (You are booked for Wednesday at half past nine, first cardiology visit. You will receive a text with the address. If you have a referral, please bring it.)
10. Caller: Благодаря. Има ли паркинг? (Thank you. Is there parking?)
11. Agent: Да, клиниката има паркинг за пациенти зад сградата. Мога ли да помогна с нещо друго? (Yes, the clinic has patient parking behind the building. Can I help with anything else?)
12. Caller: Не, това е всичко. (No, that is all.)
13. Agent: Благодаря за обаждането. Приятна вечер! (Thank you for calling. Have a good evening!)

Appointment booked in the clinic calendar, SMS confirmation sent, parking question answered from the clinic’s own information. Reception finds it in the morning; nobody had to call back.

Scripted example to illustrate behaviour. Not a recording of a real patient.

Sample conversation: Delivery line: rescheduling a parcel

English · inbound call · parcel delivery line, Sofia

1. Agent: Good afternoon, you have reached the delivery line. I am the virtual assistant. How can I help?
2. Caller: Hi. I have a parcel coming tomorrow, but I won’t be home. Can I move it?
3. Agent: Of course. Could you read me the shipment number from your text message?
4. Caller: It’s B-G four seven one nine zero two.
5. System: Looks up shipment BG471902
6. Agent: Thank you. I can see a parcel for Mladost, Sofia, due tomorrow between ten and two. I can offer Thursday from nine to twelve, or Thursday from two to six. Which works for you?
7. Caller: Thursday afternoon. And can the driver leave it with my neighbour?
8. System: Reschedules delivery to Thursday 14:00–18:00
9. Agent: Done, Thursday from two to six. About your neighbour: I don’t have a confirmed rule for that on this shipment, so I won’t promise it. I can put you through to a colleague now, or add a note for the driver. Which would you prefer?
10. Caller: Just add the note, please.
11. System: Adds driver note · sends SMS with the new window
12. Agent: Note added. You’ll get a text with the new delivery window in a moment. Anything else I can help with?
13. Caller: No, that’s it. Thanks.
14. Agent: Thank you for calling. Goodbye.

Delivery rescheduled, driver note added, SMS sent. When the question went beyond the source material, the agent said so and offered a person instead of inventing an answer.

Scripted example to illustrate behaviour. Not a recording of a real customer.

Voice & Chat Agents in detail

Real projects. Live links.

Our production voice-agent framework, client platforms and our own products. Where a project is public, the link goes to the live site, so you can check it yourself.

• Production voice-agent framework

  Voice AI · 2024. The framework behind every voice and chat agent we build: Bulgarian and English, phone and web. A reusable framework for phone and web agents that answer customer questions, take bookings and route details to the right person, around the clock. It covers knowledge bases built from real client material, a pronunciation dictionary for Bulgarian names and places, booking and lookup tools, warm transfer to a person, and a fixed back-test that runs before any change goes live. Every new agent starts from a tested base instead of a blank page, so the client-specific work goes into their knowledge, voice and tools. Voice, Telephony, Knowledge retrieval, Evaluation.

• LiveTranslations

  AI video · 2025. AI video dubbing into 29 languages, from a link or an upload. A product we built and run: paste a YouTube or TikTok link or upload a video, choose a language and receive a dubbed version. A short free preview comes before any purchase; full videos are paid with credits. Live, with the whole path from upload to dubbed result to payment running in production. Speech, Video, Payments, Web app.

• Business Outreach Optimizer

  B2B SaaS · 2024. Checks outreach emails and LinkedIn messages before they are sent. A web application that analyses email and LinkedIn drafts for spam-trigger language and weak structure, and suggests rewrites for a chosen audience. Turns the deliverability lessons from our outreach work into a tool a sales team can use before pressing send. Language models, Web app, Deliverability.

• YourLongevity

  Health and wellness · 2025. Biological-age tracking with a personalised daily protocol. A web app for tracking sleep, activity, fasting, nutrition, recovery, supplements and biomarkers, turning logged data into a longevity score and a daily protocol. A complete tracking product in daily-use shape: dashboard, timers, protocols and a paid tier. Web app, Dashboards, Personalisation, Subscriptions.

All projects

Built on platforms you can hire for, host and audit.

No house framework and no licence on your own software. What we ship runs on the tools below, in your own accounts when you prefer it that way, so another engineer can pick the system up without us.

Phone numbers come from DIDWW, a carrier with coverage in 90+ countries — which is why a voice agent we build answers a real line on day one.

Open a DIDWW account

Referral link

Small on purpose. Senior by design.

Heaven Interactive is an applied-AI engineering studio in Sofia. Three principals: two founders who are full-stack engineers and database architects, and a co-owner who is a practising lawyer. The people who scope your project are the people who build it.

• Built to run, not to demo

  We work on the part after the prototype: tests, monitoring, runbooks and restores that have actually been tried.

• Measured before it ships

  Nothing goes live without passing tests you can read. We publish no numbers we cannot show you.

• You own the code

  Full source code, deployment scripts and documentation at handover. No per-seat licence on your own software.

• EU by default

  We host in EU regions unless you decide otherwise, and a lawyer on the team writes the data terms.

• 2024 Founded
• 3 Principals
• Sofia Bulgaria, EU
• BG · EN Working languages

Denis Bozhkov

Founder · Full-stack engineer · Database architect · Engineering, data layer, runtime

Designs the data layer and the systems that run on it. Also an environment concept artist for film and games, which shows in how the studio approaches interfaces and visual craft.

• Concept art portfolio

Dimitar Roussev

Founder · Full-stack engineer · Database architect · Engineering, platform, integrations

Builds the platform side: integrations, voice and chat agents, and the infrastructure that keeps them running.

• LinkedIn

Milen Hristov

Co-owner · General counsel · Practising lawyer · Contracts, GDPR, compliance

Handles contracts, data-processing terms and regulatory questions in-house, so legal review is part of every engagement rather than an afterthought.

About the studio

Start here

Bring a real problem.

Thirty minutes with an engineer who would build it. Tell us what is breaking, what you have tried and what would change if it worked.

Book a 30-minute call · info@heaven-interactive.com

• Free, no sales pitch
• Reply within one working day
• Pricing band before any spec work