{"id":27384,"library":"seqdiag","title":"seqdiag","description":"seqdiag generates sequence-diagram images from text, part of the blockdiag family. Current version 3.0.0, requires Python >=3.7. Release cadence is sporadic.","status":"active","version":"3.0.0","language":"python","source_language":"en","source_url":"https://github.com/blockdiag/nwdiag","tags":["sequence-diagram","diagram","ascii-art","blockdiag"],"install":[{"cmd":"pip install seqdiag","lang":"bash","label":"Install via pip"}],"dependencies":[{"reason":"Core blockdiag framework required for rendering","package":"blockdiag","optional":false},{"reason":"Image generation support (for PNG output)","package":"Pillow","optional":false}],"imports":[{"wrong":"from seqdiag import parser","symbol":"parser","correct":"from seqdiag import parser"},{"wrong":"from seqdiag import builder","symbol":"builder","correct":"from seqdiag import builder"},{"wrong":"from seqdiag import drawer","symbol":"drawer","correct":"from seqdiag import drawer"}],"quickstart":{"code":"from seqdiag import parser, builder, drawer\nimport codecs\n\n# Read a .seqdiag file (or use a string)\ndiagram_text = \"\"\"\nseqdiag {\n  A -> B [label = \"request\"];\n  B -> A [label = \"response\"];\n}\n\"\"\"\n\ntree = parser.parse_string(diagram_text)\ndiagram = builder.ScreenNodeBuilder.build(tree)\n\ndrawer.draw(diagram, 'output.png', 'PNG')\n","lang":"python","description":"Generate a sequence diagram from a text description and save as PNG."},"warnings":[{"fix":"Use seqdiag.parser.parse_string() instead of the deprecated top-level seqdiag.parse().","message":"In seqdiag 3.0.0, the API changed: parser.parse_string() is the canonical way; the old top-level functions are gone.","severity":"breaking","affected_versions":"<=2.x"},{"fix":"Install fonts or set environment variable BLOCKDIAG_FONT_PATH.","message":"The seqdiag command-line tool requires the font configuration to be set correctly. Without it, generated images may lack text.","severity":"gotcha","affected_versions":"all"}],"env_vars":null,"search_vec":"'3.0.0':17 '3.7':20 'art':31 'ascii':30 'ascii-art':29 'blockdiag':13,32 'cadenc':22 'current':15 'diagram':6,27,28 'famili':14 'generat':3 'imag':7 'part':10 'python':19 'releas':21 'requir':18 'seqdiag':1,2 'sequenc':5,26 'sequence-diagram':4,25 'sporad':24 'text':9 'version':16","created_at":"2026-05-01T17:45:59.327581+00:00","updated_at":"2026-05-01T17:45:59.327581+00:00","problems":null,"ecosystem":"pypi","meta_description":null,"install_score":null,"quickstart_score":null,"quickstart_tag":null,"pypi_latest":null,"cli_name":"seqdiag","cli_version":"seqdiag 3.0.0","type":"library","homepage":"http://blockdiag.com/","github":"https://github.com/blockdiag/nwdiag","docs":null,"changelog":null,"pypi":"https://pypi.org/project/seqdiag/","npm":null,"openapi_spec":null,"status_page":null,"smithery":null,"categories":["http-networking","web-framework"],"base_url":null,"auth_type":null,"provenance":{"verified_status":"passing","verified_at":"2026-07-03","last_verified":"2026-07-03","next_check":"2026-08-02","install_tag":null}}