10/21/2026 updated
100 % available
SAP Business One Developer | Service Layer, DI API, Add-ons & E-Invoicing
Lahore, Pakistan
Only remote
Master of Information Technology, Superior University, Lahore, 2019About me
SAP B1 developer and architect since 2019 (C#/.NET, SQL Server, HANA). Add-ons, Service Layer/DI API integrations and e-invoicing (ZATCA, SRI, FEL, DTE). 100% remote from Pakistan, 13 countries. English fluent, Urdu native.
AI AgentsASP.NET.NET FrameworkApplication Programming Interfaces (APIs)C Sharp (Programming Language)SAP Crystal ReportsData IntegrationEnterprise Resource PlanningWeb PortalsMicrosoft SQL ServersSAP Business OneSAP HANAService LayerShopifyWeb Services
SAP Business One Entwickler (SAP B1) seit 2019: Add-on-Entwicklung mit dem SDK (DI API, UI API), Schnittstellen über Service Layer (Shopify, WooCommerce, CRM, Steuer- und Drittanbieter-APIs), Crystal Reports, SQL-/HANA-Abfragen, Webportale und KI auf B1-Daten. 2,5 Jahre SAP-B1-Entwickler und -Architekt für die GS Gesellschaft für Umweltschutz mbH (Schüttorf). 15 E-Invoicing-Implementierungen aus SAP B1 (live: ZATCA, SRI, FEL, DTE). 100 % remote. Anfragen auf Deutsch sind willkommen; die Abstimmung läuft schriftlich (E-Mail/Chat).
SAP Business One developer and solution architect, working since 2019 with SAP B1, C#/.NET, SQL Server and SAP HANA. 100% remote from Pakistan, for clients in 13 countries, including about 2.5 years as the SAP B1 developer and architect for a company in Germany.
Core work:
- SAP B1 add-ons and extensions with the SDK (DI API, UI API), Windows services, UDFs/UDTs and approval logic
- Integrations over Service Layer and DI API: web shops (Shopify, WooCommerce), CRMs, tax and third-party APIs, with logging, retries and readable error handling. My B1 portals and integrations process 50,000+ orders a year
- E-invoicing and tax-API integration from SAP B1: 15 implementations, live with ZATCA Phase 2 (Saudi Arabia), SRI (Ecuador), FEL (Guatemala) and DTE (El Salvador); UAE PINT-AE in progress
- Web portals on top of B1 (ASP.NET), Crystal Reports and SQL/HANA queries
- AI on ERP data: B1Codex (b1codex.com), my AI connector, MCP server and portal for SAP B1, with 90%+ query accuracy; WhatsApp AI agents on Meta's Cloud API
Typical project fit: interface and integration work, add-on development or fixes, checks and validations on master data and documents (for example tax-ID or VAT checks via external APIs), evaluating standard vs add-on vs custom code, and delivery from concept through test and handover.
Working style: remote only, clear written specs and status updates, testing on a copy of the company database before go-live, documentation at handover. Languages: English (fluent), Urdu (native).
Experience
Professional experience5 - 10 years
Freelancer since2023
Languages
EnglishFluent
Project history
Built B1Codex, a multi-company AI portal, AI connector and MCP server for SAP Business One over Service Layer and DI API (read and write, 90%+ query accuracy). Also WhatsApp AI agents on Meta's Cloud API and a native SAP B1 mobile app.
Skills: SAP B1, Service Layer, DI API, C#, .NET, MCP, AI Agents
SAP B1 customizations, DTE e-invoicing integrations, SQL procedures and Crystal Reports for distribution.
SAP B1 (HANA) APIs for a Kuwait-based food-service group (subscriptions, POS, retail and daily cost; live with 2,700+ subscriptions). Automated Sales Orders, A/R Invoices, Payments, Goods Issues and Journal Entries with pre-validation; BOM-based production add-on.
Skills: SAP B1, SAP HANA, Service Layer, REST API, C#