{"type":"post","id":"dspy-3-4-0-out-with-1-native-4439f5","slug":"dspy-3-4-0-out-with-1-native-4439f5","title":"DSPy 3.4.0 out, with: (1) native support for Jev and System One models - in the timeless DSPy syntax.","description":"DSPy 3.4.0 moves probability-bearing decisions closer to the program interface, making calibration a first-class concern for agent workflows rather than an external post-processing step.","retrieval_nugget":"DSPy 3.4.0 moves probability-bearing decisions closer to the program interface, making calibration a first-class concern for agent workflows rather than an external post-processing step.","published_at":"2026-09-25","updated_at":"2026-09-25","record_date":"2026-09-25","date_kind":"published_at","topics":[],"source_urls":["https://github.com/stanfordnlp/dspy/releases/tag/3.4.0"],"schema_version":"newruntime-agent-readable-v0.2","stable_id":"post:dspy-3-4-0-out-with-1-native-4439f5","status":"published","visuals":[],"editorial_provenance":{"schema_version":"newruntime-editorial-copy-v1","content_status":"source_grounded_final","final_copy_sha256":"sha256:bba6f63ef96d381924457c5488267c982504a6058da201fb652fccc2f5db27a1","reviewed_at":"2026-09-25T20:05:00.485Z","source_evidence_count":1,"verified_claim_count":3,"site_analysis_schema_version":"newruntime-site-analysis-v1","site_object_kind":"field_note","observed_fact_count":3,"implication_count":2,"watch_condition_count":2,"related_record_count":0},"analysis":{"schema_version":"newruntime-site-analysis-v1","object_kind":"field_note","thesis":"DSPy 3.4.0 moves probability-bearing decisions closer to the program interface, making calibration a first-class concern for agent workflows rather than an external post-processing step.","observed_facts":[{"text":"The release introduces Jev through the TypeSafe client and defines three experimental decision types: Noul for Boolean decisions, Choice for selecting among described alternatives, and Score for ordered rubrics.","source_urls":["https://github.com/stanfordnlp/dspy/releases/tag/3.4.0"]},{"text":"The release notes say ReAnchor fits Boolean thresholds, Score cuts, and Choice weights in Predict programs without rewriting instructions, criteria, or demonstrations.","source_urls":["https://github.com/stanfordnlp/dspy/releases/tag/3.4.0"]},{"text":"DSPy identifies 3.4 as its LM transition release and says 3.5 is the migration deadline for the replaced experimental LM types.","source_urls":["https://github.com/stanfordnlp/dspy/releases/tag/3.4.0"]}],"mechanism":"The mechanism is local decision policy layered over a DSPy predictor. Thresholds, score cuts, and choice weights are applied locally, which the release says allows identical backend requests to reuse cached evidence.","why_now":"This matters now because DSPy calls version 3.4 its LM transition release and names 3.5 as the migration deadline.","implications":["The implication is that teams can separate an underlying model’s evidence from the operational rule that turns that evidence into routing or escalation behavior.","Existing DSPy users with legacy custom-LM integrations or OpenAI-style messages= calls have a defined migration window but should test compatibility before 3.5."],"evidence_boundary":"Evidence boundary: the release notes describe experimental APIs and do not establish that these outputs are statistically calibrated in every setting.","watch_conditions":["Watch whether ReAnchor improves held-out operational metrics across real decision workflows, rather than only fitting thresholds on a development dataset.","Watch whether TypeSafe/Jev support expands beyond top-level decision outputs and the currently unsupported streaming, RLM decision-output, and generative optimization paths."],"related_records":[],"new_branch_reason":"No prior New Runtime record was supplied; this release starts a distinct record because it combines a new decision backend, calibration optimizer, and explicit LM migration milestone."},"editor":{"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]},"routes":{"html":"https://newruntime.com/posts/dspy-3-4-0-out-with-1-native-4439f5/","markdown":"https://newruntime.com/posts/dspy-3-4-0-out-with-1-native-4439f5.md","json":"https://newruntime.com/posts/dspy-3-4-0-out-with-1-native-4439f5.json"},"next_reads":[{"type":"collection","path":"/posts/","url":"https://newruntime.com/posts/","title":"Field Notes","reason":"Open the latest editorial analysis.","media_type":"text/html","json_url":"https://newruntime.com/posts.json"},{"type":"collection","path":"/source-ledger.json","url":"https://newruntime.com/source-ledger.json","title":"Source Ledger","reason":"Inspect the public source evidence graph.","media_type":"application/json"}]}