Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!
DOT
DOT is an abstract grammar for defining Graphviz nodes, edges, graphs, subgraphs, and clusters.
diagrams
Diagrams is a Python package for prototyping cloud system architectures. It is the best text/code-based diagram/workflow tool.
PlantUML
Please refer to Tips on PlantUML for more details.
mermaid
mermaid is a Javascript based diagramming and charting tool that uses Markdown-inspired text definitions and a renderer to create and modify complex diagrams.
Code2Flow
Code2Flow is a pseudo-programming language like (and thus familiar and friendly to programmers) text to flowchart tool. It is a commercial service but free plan is available.
flowchart.js
flowchart.js draws simple SVG flow chart diagrams from textual representation of the diagram .
Mappio
Mappio is an online text to flowchart tool. It is better than Text2MindMap
ditaa
Chart Mage
Chart Mage is similar to PlantUML. It is text-to-UML tool but also supports flowchart. Chart Mage is less popular compared to PlantUML.
Gaphor
Gaphor is the simple UML tool.