Experience

Part-time maintenance of the iTcl/Tk-based graphical user interface.

Author of a Tk extension (now lost) for creating Tcl-scripted canvas items based on libcairo.

Occasional drive-by fixes in ExtJS.

Implemented and maintained interfaces to various external systems:

• e-mail via SMTP, POP3, IMAP, MSGraph
• ISO20022 messaging
• ISO8583 based communication (Base24 & ASX)
• LDAP
• medical protocols: HL7 and LDT

Introduced and maintained scripting capabilities with Tcl & Python in the backend. Used nanobind and the Tcl C-API to provide a clean integration of backend features at the scripting level.

Authored various scripted components based on these APIs: modules for free text analysis, decision tree evaluation, and assorted parsers and builders.

Primarily responsible for the OpenSSL infrastructure: SSL/TLS-protected communication channels, custom cryptography processing units, support for hardware security modules, and a Tcl wrapper package that makes cryptographic primitives available to Tcl scripts.

Design and implementation of a Tcl-scriptable FastCGI authorization framework.

Integration of external authentication with the product-native permissioning.

Implementation of an OpenIDConnect authorizer.

Design and implementation of a generic reporting engine that supports multi-tenancy and is tightly integrated with the application’s permissioning model. It is based on a custom virtual table implementation in SQLite that combines SQL data with data from LDAP and other optional sources.

Assisted in the creation of an AWS-hosted, RAG-based chat companion.

Avid user of Claude Code; currently experimenting with MCP server development.

Implemented a Tcl wrapper library for OpenCL and used it to develop GPU kernels that implement exact linear algebra over the field \({\mathbb F}_2\) and routines related to the mod \(2\) Steenrod algebra. Also added a Tcl interface to OpenTelemetry to debug the performance of this solution.