## 1. Why Kontaktu is Suitable for Fragile and Conflicted-Affected States

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---

### Summary of Workshop Activities
- IMF workshop on tax administration digitalization in fragile and conflict-affected states (FCS), delivered jointly by the IMF Fiscal Affairs Department (FAD) and the Middle East Technical Assistance Center (METAC).
- Venue and date: Cairo Marriott Hotel & Omar Khayyam Casino in Cairo, Egypt, from November 30 to December 3.
- IMF facilitators: Ms. Fadia Sakr, Ms. Sabine Corm, Mr. Joshua Aslett, and Mr. Paulo Paz; short-term IMF experts Gustavo Figueiredo and Rivelino Patrício.
- Participants: representatives from Iraq, Libya, and Yemen (Annex I).
- Workshop objectives:
  - Share country experiences and discuss fundamentals of tax administration.
  - Explore the Kontaktu IT platform as an innovative option for digitalization in FCS contexts.
  - Maintain objectivity among participants regarding digitalization models (commercial ITAS acquisition, in-house development, or alternative models).
  - Support decision-making on whether Kontaktu is suitable in each country’s circumstances.
- IMF support stance:
  - IMF will support digitalization independently of platform choice.
  - For countries interested in Kontaktu, IMF can provide follow-on support to scope implementation projects, which may involve self-financing and development partner support.
  - Formal request required to initiate IMF-supported Kontaktu implementation.
  - If Kontaktu is unsuitable, IMF remains available to support other digitalization approaches.

### Digitalization as an Imperative for Efficient Revenue Mobilization
- Core arguments:
  - Digitalization is essential for domestic revenue mobilization and efficient tax administration.
  - Modern compliance risk management (CRM) strategies rely on comprehensive data sets and modern IT systems to identify, rank, and prioritize tax compliance risks.
  - Digitalization improves taxpayer access to services (registration, filing, payment, accurate reporting) and enhances transparency and reduces corruption.
- Two established digitalization paths:
  - Acquisition of a commercial-off-the-shelf Integrated Tax Administration System (ITAS):
    - Typically covers comprehensive work streams and electronic taxpayer services and internal modules.
    - Downsides: can be expensive, require complex procurement, entail medium to long-term commitments, limited flexibility or costly customization, designed primarily for stable tax environments.
    - Jurisdictions sometimes adapt tax systems to fit IT solutions.
  - In-house IT system development:
    - Advantages: tailored design, progressive implementations, greater flexibility.
    - Disadvantages: longer development and deployment time, requires solid and stable sponsorship, risk of lack of experience mitigated by technical assistance.
- Challenges for FCSs:
  - Financing, stability, and ability to execute long-running projects make both established options challenging in FCS early digitalization stages.

### An Alternate Option: Kontaktu
- Origins and rationale:
  - Developed by the IMF in response to a member country request during the COVID-19 pandemic when face-to-face tax interactions were shut down and fiscal constraints prevented investment in a new IT system.
  - Initially developed as a lightweight Minimum Viable Product (MVP) website for electronic filing and payment, delivered entirely remotely.
  - Successfully deployed in the pilot country and subsequently approved by the IMF for other FCS member tax administrations.
- Design priorities for FCS contexts:
  - Built for challenging environments where electricity and basic internet connectivity may be unstable, and where IT infrastructure and financial resources are limited.
  - Multi-language, open-source, generic tool using enterprise-grade and free software.
  - Hosting options: commercial clouds or government servers.
  - Access via computers and smartphones.
  - MVP software delivered free of cost, with source code and manuals.
  - Countries may adopt entire solution or specific modules; free to use as intended or modify features at discretion.
- Classification:
  - Kontaktu is considered a “digital public good” (open-source software, standards, models, data sets, and content that are freely accessible and designed to address global challenges, especially in low-resource settings).

### Key Features and Advantages of Kontaktu (Box 1)
- Customizable and Flexible: adaptable to meet country-specific requirements without needing to modify the source code; adding new tax declarations is simple.
- Low Internet Dependency: taxpayers can complete tasks offline and upload declarations once internet access is available.
- Modular Design: phased implementation starting with basic functionalities and gradually adding features.
- Low Maintenance Cost: can be installed on-premises or hosted using cloud providers, requiring minimal resources to operate.
- Use of Market Standards: built with technologies such as microservices, Docker, and Java.
- Robust Security: access controlled by user roles; employs industry-standard measures to prevent cyberattacks.
- Software Provided Free of Cost: software and source code entirely free of charge.
- Interactive Data Analysis: built-in tools for generating comprehensive reports directly from the database usable by non-IT staff.
- Automated Data Exchange: tools facilitate seamless data sharing with other departments through simple, preconfigured steps.
- Flexibility to Adapt: new taxes can be added without altering the platform; machine-learning integration ensures scalability and efficiency.
- Electronic Notifications: integrated modules enable automated, low-cost communication with taxpayers.
- Simplified Payment Process: supports collection of any tax or fee within the country.
- Resilience Against Failures or Attacks: built-in backup features allow secure replication across multiple servers, including geographically separated locations, ensuring business continuity.

### Proposed Next Steps and Implementation Scenario
- Decision framework:
  - Determine most suitable digitalization option in country context: (a) commercial ITAS acquisition; (b) in-house custom development; or (c) Kontaktu implementation.
  - Kontaktu, provided as a digital public good (free of cost for software), may serve as a transitionary measure to jump-start digitalization before pursuing established options.
- IMF role and required action:
  - IMF available to help navigate options.
  - For concrete interest in Kontaktu, the next step is to send a letter requesting further support; IMF will organize follow-up to scope an implementation project including business process review, implementation, technical and operational training.
  - Typical project focus: start with a small number of taxes and taxpayers (e.g., large taxpayer office) before wider deployment.
- Example first-year project outline (to be adjusted per circumstances):
  - A series of four to six remote preparatory meetings to share legislation, dissect administrative processes, identify stakeholders, and refine agenda.
  - An Inaugural HQ mission – preferably in person with an IMF team of four to six members; conclude with a diagnostic of two or three core items for pilot phase (e.g., registration and filing); strategic decisions made during this mission.
  - Post-mission remote meetings to finalize diagnostic and next steps.
  - Complementary remote short-term expert (STX) engagements – four to six engagements over the course of one year.
- Governance and political support:
  - Example specific to Libya: because the General Commission of Tax in Libya is not an autonomous administration, support from the Ministry of Finance is essential to provide authority to promote changes and drive initiative forward.
  - Strong political commitment encourages collaboration among stakeholders.

### Requisites for a Successful Implementation of Kontaktu (Box 2)
- Support:
  - Support from the Ministry of Finance and leadership in tax administration is the most critical factor for change management.
- Project structure and roles:
  - Appoint a general project manager to oversee the initiative, with submanagers for legal, core business processes, IT, and communication to ensure clear accountability.
  - Designate a core team of dedicated professionals to coordinate efforts across departments.
- Legal framework:
  - Modify the digitization legal framework to ensure legal equivalence of paper-based and online processes.
- Communication:
  - Prepare an effective communication campaign to explain benefits to taxpayers, employees, and stakeholders to overcome cultural barriers.
- Key implementation decisions to address:
  - (i) which modules to develop initially;
  - (ii) appetite / capability for the project;
  - (iii) when it is possible to start;
  - (iv) who will be the core team;
  - (v) how to ensure internet availability;
  - (vi) where to host it (cloud or on-premises);
  - (vii) how many taxpayers will be in the pilot phase.

### Annex I. Description of Kontaktu — Platform overview
- Kontaktu is a user-friendly web platform designed to support Tax Administrations in managing and streamlining their digital services.
- Connects taxpayers, internal tax officers, payment authorities (like banks and mobile payment agents), customs, and treasury departments to create a seamless workflow.
- Built with reliable open-source technologies; flexible, fully customizable and scalable.
- Can operate securely on the public Internet, hosted in a cloud environment or within on-premises systems.

### Annex I. Key features — Versatile Modeling Tax Returns
- Can be set up to fit the needs of tax administration with almost no need to adjust the source code.
- New tax declaration templates can be learned by the system to provide self-assessment online services.
- Employs machine learning heuristics and a schemaless data storage approach to extract necessary information.
- Template-driven: providing a template file (e.g., an Excel spreadsheet) allows the platform to automatically adapt to the underlying data structure.
- Eliminates the need for specialized teams to design rigid data structures and extensive validation code.

### Annex I. Key features — Modern Infrastructure (module suite)
- Modular components enable selective enabling of features for external and internal use.
- Modules include:
  - Taxpayers Registry: keeps record of taxpayers registry information, including geo references and internal relationships; may integrate with external taxpayer registry systems; can automatically generate new taxpayer identification numbers.
  - Filing Module: models and receives tax returns and other tax-related forms; supports Excel, Word, PDF, XML file formats; files stored in a schemaless database.
  - Payments Module: controls tax payments using external payment platforms via APIs.
  - Invoices Module: implements 'online invoice' in different styles and controls authorization of invoice issuance.
  - Communication Module: supports internal communications, official reports, legislation, instructions; messages viewable online or sent by e-mail or mobile app instant messages.
  - Tax Domicile Module: implements an 'Electronic Tax Domicile' for delivering tax notifications with deadline control awareness.
  - Tax Credit and Previous Loss Module: features for tax credit balance control, tax credit claims and previous loss control used with debt compensations.
  - Export Module: supply chain management for export operations, including stock control of goods to be exported.
  - Integration Agents Module: uses a distributed net of 'integration agents' useful for IoT and integrating databases and services from different government agencies.

### Annex I. Key features — Scalability and Security
- Robust architecture supports horizontal scalability and adapts to flexible data structures.
- Data is stored using No-SQL data storage, including replication and sharding capabilities.
- Security measures included:
  - Compliant encryption policy: configuration and use of digital certificates for encryption of the communication channel, ensuring use of current encryption algorithms.
  - Container isolation: containerized architecture where each internal component only connects to intended interfaces.
  - Automatic blocking for suspected intrusion attempts: entry point actively monitors unsuccessful login attempts and enables automatic blocking of suspicious sources.
  - Backup strategy: built-in capability to replicate and keep synchronized one or more replicas of the entire system in different locations.
  - Security in back and front ends: strict Content Security Policies, Cross-Site Request Forgery tokens, configurable privileges and user profiles related to Rule Based Access Control conforming to the principle of least privilege, adoption of open standards (OpenId/OAUTH) for user authentication using pluggable identity providers, adoption of strong password policies, rate limiting via reCAPTCHA protection, enforcement of TLS/SSL externally and internally, validation and treatment of user input to prevent XSS and other injection attacks.
  - Logging system: user activity is registered and logged for later querying by IT teams to spot suspicious events.

### Annex I. Key features — Technological Autonomy for the Business Area
- Empowers business teams to design and implement strategic decisions without relying on IT support.
- Includes a data analysis tool designed for non-IT specialists to perform data cross matching with multiple sources.
- Supported data types for matching: VAT and CIT returns, taxpayers registry, customs data, electronic invoices, tax payments, payroll, real estate and IoT collected data.
- Enables building dashboards with various charts and maps including geo-located taxpayer data.

### Annex II. Technical Specifications
- Programming language: Java (backend); Javascript, CSS, HTML (frontend); Groovy (scripts).
- Programming Framework and Libraries: Spring / SpringBoot, Thymeleaf, JQuery, Semantic UI, Tabulator JS, Codemirror, ToastUI.
- Internal Database: ElasticSearch (with multiple data nodes).
- Reverse Proxy: NGINX.
- Digital Certificate Provider: Lets Encrypt.
- Container Orchestration: Docker Compose (also possible to use with Kubernetes).
- Dashboards: Kibana.
- Development Tools: Maven, Eclipse, GIT.
- Supported Input File Formats: Excel (XLS, XLSX, XLSM), Word (DOC, DOCX), PDF (including forms), CSV, XML, JSON.
- Supported Databases (for data exchange): SQL Server, My SQL, Oracle Database, Postgre, Firebird.

### Annex III. Minimal Hardware Requirements
- Deployment: cluster with multiple hosts, cloud or on-prem.
- Simplest single-server configuration specifications:
  - RAM Memory: 32 GB
  - CPU: 4 cores x86_64
  - Disk: 60 GB SSD
  - OS: Linux 64 bits (RedHat, CentOS or similar)
  - Connectivity: accessible externally by port 443 (SSL)
  - Any public external domain name to be assigned to Kontaktu server.

### Annex V. Taxpayer Experience — Filing workflow
- Step 1: Download the template for the tax return from the Kontaktu server via the public Internet Address defined by the Tax Administration; template file formats include Excel, Word, PDF (including forms).
- Step 2: Fill in the fields in the template; templates are usually protected to allow changes only in designated parts and may include local validations and pre-defined formulas; filling can be done offline without Internet connectivity.
- Step 3: Taxpayer logs into Kontaktu using a previously provided user account assigned to a taxpayer identification number related to the company; Kontaktu enforces authorization rules to prevent unauthorized submissions.
- Step 4: Taxpayer uploads the file (takes 2 clicks to reach upload); Kontaktu performs data validations and rejects files with errors, missing data or unauthorized access; on success, a confirmation is provided and related tax payment slips are automatically generated and available.

*Annex I. Description of Kontaktu — tarea2025059-print-pdf.*

### 1. Why Kontaktu is Suitable for Fragile and Conflicted-Affected States .................................................

### 1. Why Kontaktu is Suitable for Fragile and Conflicted-Affected States

### Summary of Workshop Activities
- The IMF held a workshop on tax administration digitalization in fragile and conflict-affected states (FCS), delivered jointly by the IMF Fiscal Affairs Department (FAD) and the Middle East Technical Assistance Center (METAC).
- Workshop venue and date: Cairo Marriott Hotel & Omar Khayyam Casino in Cairo, Egypt, from November 30 to December 3.
- IMF facilitators: Ms. Fadia Sakr, Ms. Sabine Corm, Mr. Joshua Aslett, and Mr. Paulo Paz; short-term IMF experts Gustavo Figueiredo and Rivelino Patrício.
- Participants: representatives from Iraq, Libya, and Yemen (Annex I).
- Workshop objectives:
  - Share country experiences and discuss fundamentals of tax administration.
  - Explore the Kontaktu IT platform as an innovative option for digitalization in FCS contexts.
  - Maintain objectivity among participants regarding digitalization models (commercial ITAS acquisition, in-house development, or alternative models).
  - Support decision-making on whether Kontaktu is suitable in each country’s circumstances.
- IMF support stance:
  - IMF will support digitalization independently of platform choice.
  - For countries interested in Kontaktu, IMF can provide follow-on support to scope implementation projects, which may involve self-financing and development partner support.
  - Formal request required to initiate IMF-supported Kontaktu implementation.
  - If Kontaktu is unsuitable, IMF remains available to support other digitalization approaches.

### Digitalization as an Imperative for Efficient Revenue Mobilization
- Core arguments:
  - Digitalization is essential for domestic revenue mobilization and efficient tax administration.
  - Modern compliance risk management (CRM) strategies rely on comprehensive data sets and modern IT systems to identify, rank, and prioritize tax compliance risks.
  - Digitalization improves taxpayer access to services (registration, filing, payment, accurate reporting) and enhances transparency and reduces corruption.
- Two established digitalization paths:
  1. Acquisition of a commercial-off-the-shelf Integrated Tax Administration System (ITAS):
     - Typically covers comprehensive work streams and electronic taxpayer services and internal modules.
     - Downsides: can be expensive, require complex procurement, entail medium to long-term commitments, limited flexibility or costly customization, designed primarily for stable tax environments.
     - Jurisdictions sometimes adapt tax systems to fit IT solutions.
  2. In-house IT system development:
     - Advantages: tailored design, progressive implementations, greater flexibility.
     - Disadvantages: longer development and deployment time, requires solid and stable sponsorship, risk of lack of experience mitigated by technical assistance.
- Challenges for FCSs:
  - Financing, stability, and ability to execute long-running projects make both established options challenging in FCS early digitalization stages.

### An Alternate Option: Kontaktu
- Origins and rationale:
  - Kontaktu was developed by the IMF in response to a member country request during the COVID-19 pandemic when face-to-face tax interactions were shut down and fiscal constraints prevented investment in a new IT system.
  - Initially developed as a lightweight Minimum Viable Product (MVP) website for electronic filing and payment, delivered entirely remotely.
  - Successfully deployed in the pilot country and subsequently approved by the IMF for other FCS member tax administrations.
- Design priorities for FCS contexts:
  - Built for challenging environments where electricity and basic internet connectivity may be unstable, and where IT infrastructure and financial resources are limited.
  - Multi-language, open-source, generic tool using enterprise-grade and free software.
  - Hosting options: commercial clouds or government servers.
  - Access via computers and smartphones.
  - MVP software delivered free of cost, with source code and manuals.
  - Countries may adopt entire solution or specific modules; free to use as intended or modify features at discretion.
- Classification:
  - Kontaktu is considered a “digital public good” (open-source software, standards, models, data sets, and content that are freely accessible and designed to address global challenges, especially in low-resource settings).

### Key Features and Advantages of Kontaktu (Box 1)
- Customizable and Flexible: adaptable to meet country-specific requirements without needing to modify the source code; adding new tax declarations is simple.
- Low Internet Dependency: taxpayers can complete tasks offline and upload declarations once internet access is available.
- Modular Design: phased implementation starting with basic functionalities and gradually adding features.
- Low Maintenance Cost: can be installed on-premises or hosted using cloud providers, requiring minimal resources to operate.
- Use of Market Standards: built with technologies such as microservices, Docker, and Java.
- Robust Security: access controlled by user roles; employs industry-standard measures to prevent cyberattacks.
- Software Provided Free of Cost: software and source code entirely free of charge.
- Interactive Data Analysis: built-in tools for generating comprehensive reports directly from the database usable by non-IT staff.
- Automated Data Exchange: tools facilitate seamless data sharing with other departments through simple, preconfigured steps.
- Flexibility to Adapt: new taxes can be added without altering the platform; machine-learning integration ensures scalability and efficiency.
- Electronic Notifications: integrated modules enable automated, low-cost communication with taxpayers.
- Simplified Payment Process: supports collection of any tax or fee within the country.
- Resilience Against Failures or Attacks: built-in backup features allow secure replication across multiple servers, including geographically separated locations, ensuring business continuity.
- For further technical details, refer to Annexes II to V (technical specifications, minimal hardware requirements, security test results).

### Proposed Next Steps and Implementation Scenario
- Decision framework:
  - Determine most suitable digitalization option in country context: (a) commercial ITAS acquisition; (b) in-house custom development; or (c) Kontaktu implementation.
  - Kontaktu, provided as a digital public good (free of cost for software), may serve as a transitionary measure to jump-start digitalization before pursuing established options.
- IMF role:
  - IMF available to help navigate options.
  - For concrete interest in Kontaktu, the next step is to send a letter requesting further support; IMF will organize follow-up to scope an implementation project including business process review, implementation, technical and operational training.
  - Typical project focus: start with a small number of taxes and taxpayers (e.g., large taxpayer office) before wider deployment.
- Example first-year project outline (to be adjusted per circumstances):
  - A series of four to six remote preparatory meetings to share legislation, dissect administrative processes, identify stakeholders, and refine agenda.
  - An Inaugural HQ mission – preferably in person with an IMF team of four to six members; conclude with a diagnostic of two or three core items for pilot phase (e.g., registration and filing); strategic decisions made during this mission.
  - Post-mission remote meetings to finalize diagnostic and next steps.
  - Complementary remote short-term expert (STX) engagements – four to six engagements over the course of one year.
- Governance and political support:
  - Example specific to Libya: because the General Commission of Tax in Libya is not an autonomous administration, support from the Ministry of Finance is essential to provide authority to promote changes and drive initiative forward.
  - Strong political commitment encourages collaboration among stakeholders.

### Requisites for a Successful Implementation of Kontaktu (Box 2)
- Support:
  - Support from the Ministry of Finance and leadership in tax administration is the most critical factor for change management.
- Project structure and roles:
  - Appoint a general project manager to oversee the initiative, with submanagers for legal, core business processes, IT, and communication to ensure clear accountability.
  - Designate a core team of dedicated professionals to coordinate efforts across departments.
- Legal framework:
  - Modify the digitization legal framework to ensure legal equivalence of paper-based and online processes.
- Communication:
  - Prepare an effective communication campaign to explain benefits to taxpayers, employees, and stakeholders to overcome cultural barriers.
- Key implementation decisions to address:
  - (i) which modules to develop initially;
  - (ii) appetite / capability for the project;
  - (iii) when it is possible to start;
  - (iv) who will be the core team;
  - (v) how to ensure internet availability;
  - (vi) where to host it (cloud or on-premises);
  - (vii) how many taxpayers will be in the pilot phase.

*IMF | FAD - METAC Libya | Content unit: 1. Why Kontaktu is Suitable for Fragile and Conflicted-Affected States*

### Annex I.   Description of Kontaktu

### Annex I.   Description of Kontaktu

### Platform overview
- Kontaktu is a user-friendly web platform designed to support Tax Administrations in managing and streamlining their digital services.
- Connects taxpayers, internal tax officers, payment authorities (like banks and mobile payment agents), customs, and treasury departments to create a seamless workflow.
- Built with reliable open-source technologies; flexible, fully customizable and scalable.
- Can operate securely on the public Internet, hosted in a cloud environment or within on-premises systems.

### Key features — Versatile Modeling Tax Returns
- Can be set up to fit the needs of tax administration with almost no need to adjust the source code.
- New tax declaration templates can be learned by the system to provide self-assessment online services.
- Employs machine learning heuristics and a schemaless data storage approach to extract necessary information.
- Template-driven: providing a template file (e.g., an Excel spreadsheet) allows the platform to automatically adapt to the underlying data structure.
- Eliminates the need for specialized teams to design rigid data structures and extensive validation code.

### Key features — Modern Infrastructure (module suite)
- Modular components enable selective enabling of features for external and internal use.
- Modules include:
  - Taxpayers Registry: keeps record of taxpayers registry information, including geo references and internal relationships; may integrate with external taxpayer registry systems; can automatically generate new taxpayer identification numbers.
  - Filing Module: models and receives tax returns and other tax-related forms; supports Excel, Word, PDF, XML file formats; files stored in a schemaless database.
  - Payments Module: controls tax payments using external payment platforms via APIs.
  - Invoices Module: implements 'online invoice' in different styles and controls authorization of invoice issuance.
  - Communication Module: supports internal communications, official reports, legislation, instructions; messages viewable online or sent by e-mail or mobile app instant messages.
  - Tax Domicile Module: implements an 'Electronic Tax Domicile' for delivering tax notifications with deadline control awareness.
  - Tax Credit and Previous Loss Module: features for tax credit balance control, tax credit claims and previous loss control used with debt compensations.
  - Export Module: supply chain management for export operations, including stock control of goods to be exported.
  - Integration Agents Module: uses a distributed net of 'integration agents' useful for IoT and integrating databases and services from different government agencies.

### Key features — Scalability and Security
- Robust architecture supports horizontal scalability and adapts to flexible data structures.
- Data is stored using No-SQL data storage, including replication and sharding capabilities.
- Security measures included:
  - Compliant encryption policy: configuration and use of digital certificates for encryption of the communication channel, ensuring use of current encryption algorithms.
  - Container isolation: containerized architecture where each internal component only connects to intended interfaces.
  - Automatic blocking for suspected intrusion attempts: entry point actively monitors unsuccessful login attempts and enables automatic blocking of suspicious sources.
  - Backup strategy: built-in capability to replicate and keep synchronized one or more replicas of the entire system in different locations.
  - Security in back and front ends: strict Content Security Policies, Cross-Site Request Forgery tokens, configurable privileges and user profiles related to Rule Based Access Control conforming to the principle of least privilege, adoption of open standards (OpenId/OAUTH) for user authentication using pluggable identity providers, adoption of strong password policies, rate limiting via reCAPTCHA protection, enforcement of TLS/SSL externally and internally, validation and treatment of user input to prevent XSS and other injection attacks.
  - Logging system: user activity is registered and logged for later querying by IT teams to spot suspicious events.

### Key features — Technological Autonomy for the Business Area
- Empowers business teams to design and implement strategic decisions without relying on IT support.
- Includes a data analysis tool designed for non-IT specialists to perform data cross matching with multiple sources.
- Supported data types for matching: VAT and CIT returns, taxpayers registry, customs data, electronic invoices, tax payments, payroll, real estate and IoT collected data.
- Enables building dashboards with various charts and maps including geo-located taxpayer data.

### Technical Specifications (Annex II)
- Programming language: Java (backend); Javascript, CSS, HTML (frontend); Groovy (scripts).
- Programming Framework and Libraries: Spring / SpringBoot, Thymeleaf, JQuery, Semantic UI, Tabulator JS, Codemirror, ToastUI.
- Internal Database: ElasticSearch (with multiple data nodes).
- Reverse Proxy: NGINX.
- Digital Certificate Provider: Lets Encrypt.
- Container Orchestration: Docker Compose (also possible to use with Kubernetes).
- Dashboards: Kibana.
- Development Tools: Maven, Eclipse, GIT.
- Supported Input File Formats: Excel (XLS, XLSX, XLSM), Word (DOC, DOCX), PDF (including forms), CSV, XML, JSON.
- Supported Databases (for data exchange): SQL Server, My SQL, Oracle Database, Postgre, Firebird.

### Minimal Hardware Requirements (Annex III)
- Deployment: cluster with multiple hosts, cloud or on-prem.
- Simplest single-server configuration specifications:
  - RAM Memory: 32 GB
  - CPU: 4 cores x86_64
  - Disk: 60 GB SSD
  - OS: Linux 64 bits (RedHat, CentOS or similar)
  - Connectivity: accessible externally by port 443 (SSL)
  - Any public external domain name to be assigned to Kontaktu server.

### Taxpayer Experience (Annex V) — Filing workflow
- Step 1: Download the template for the tax return from the Kontaktu server via the public Internet Address defined by the Tax Administration; template file formats include Excel, Word, PDF (including forms).
- Step 2: Fill in the fields in the template; templates are usually protected to allow changes only in designated parts and may include local validations and pre-defined formulas; filling can be done offline without Internet connectivity.
- Step 3: Taxpayer logs into Kontaktu using a previously provided user account assigned to a taxpayer identification number related to the company; Kontaktu enforces authorization rules to prevent unauthorized submissions.
- Step 4: Taxpayer uploads the file (takes 2 clicks to reach upload); Kontaktu performs data validations and rejects files with errors, missing data or unauthorized access; on success, a confirmation is provided and related tax payment slips are automatically generated and available.

*Annex I. Description of Kontaktu — tarea2025059-print-pdf.*

---


_Source: https://www.imf.org/-/media/files/publications/tar/2025/english/tarea2025059-print-pdf.pdf_