Delta-Soft recognize an importance of Open Source movement and share its philosophy. We contribute to several OSS projects, such as most advanced open source database in the world - PostgreSQL.

PostreSQL development

Oleg Bartunov and Teodor Sigaev are recognized PostgreSQL developers. Delta-Soft is sponsoring their work on:

  • Core GiST development
    GiST (Generalized Search Tree) provides a possibility to create a custom data types with indexed access methods and extensible set of queries for specific domain experts not a database one. Current implementation of GiST supports:
    • Variable length keys
    • Composite keys (multi-key)
    • provides NULL-safe interface to GiST core
  • Development of specialized data types (most of them are included into PostgreSQL distribution)
    • rtree_gist, btree_gist - GiST implementation of R-Tree and B-Tree structures
    • intarray - index support for one-dimensional array of integers
    • ltree - data types, indexed access methods and queries for data organized as a tree-like structures
    • tsearch2 - a searchable (full text) data type with indexed access
    • hstore - Storage for semistructural data with index access
    • pg_trgm - provides functions and index classes for determining the similarity of text based on trigram matching.
  • - our contribution to PostgreSQL community, features search engine on postgresql related internet resources (weekly update), searchable mailing list archive (updated online).

More information is available from GiST development page.

Information Retrieval

  • Delta-Soft sponsors development of OpenFTS - full text search engine, that provides online indexing of data and relevance ranking for database searching. Close integration with database allows use of metadata to restrict search results.
  • We participate in development of pgSphere, which provides spherical data types, functions and operators for PostgreSQL and intended to store and retrieve data from very big astronomical catalogues (see pgAstro for future development).
  • Perl interface to Snowball stemmers -- This module provides unified perl interface to Snowball stemmers ( and virtually supports various languages. It's written using C for high performance and provides OO and plain interfaces.

Open source advocacy

We promote Open source through:

  • using OSS products in our projects
  • following open standards in our technology
  • lectures, talks on conferences
  • articles and papers in offline/online media
  • IT consulting and auditing