DESDEO 2.3.0

[2.3.0] - 31.3.2026

Core logic

Added

• Added lagrange_multipliers field to SolverResults; extract duals from
  Ipopt, Bonmin, and Gurobi solvers.
• Added desdeo/explanations/lagrange.py with filter, tradeoff, and
  active-objective utilities for Lagrange multiplier analysis.
• Added unit tests for Lagrange utilities and solver integration tests.

Fixed

• Fixed a bug where ScipyMinimizeSolver and ScipyDeSolver returned incorrect
  solutions for problems with maximize=True objectives.
• Fixed infinite loop in the Dmitry forest problem (use
  Path(__file__).resolve() instead of searching for "DESDEO" folder name).

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Web API

Added

• Added get-multipliers-info endpoint to the NIMBUS router.
• Added XNIMBUS (Explainable NIMBUS) StateKinds, state fields, and API
  models (NIMBUSMultiplierRequest/Response).
• Added XNIMBUS router with explainability endpoints; registered in app.py.
• Added XNIMBUS API endpoint tests.

Changed

• Removed singleton request model classes (ProblemGetRequest,
  GetSessionRequest, RepresentativeSolutionSetRequest) and refactored
  endpoints to use query parameters instead.
• Refactored SessionContextGuard: replaced __call__ with
  .post/.get/.delete methods to eliminate spurious requestBody on
  GET/DELETE endpoints in the OpenAPI schema.
• Fixed SessionContextGuard swapped-arguments bug (fetch_interactive_session
  called with request/session reversed).

Fixed

• Fixed cookies being set to Secure in dev mode, which broke the UI over HTTP
  connections (e.g., WSL). The Secure flag is now derived from the SvelteKit
  dev environment setting.

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Web GUI

Added

• Added XNIMBUS (Explainable NIMBUS) frontend route with explainable layout,
  advanced sidebar, explanation bar charts, and help dialog.
• Added Explainable NIMBUS to the method selection/initialize view.
• Added custom 404 error page.
• Added registration and forgot-password placeholder pages; fixed links
  on the login page.
• Added visual indicators on the login form.
• Added page titles and meta descriptions to all frontend routes.

Changed

• Fully migrated to Orval-generated endpoints: replaced all api.GET/api.POST
  calls with Orval-generated endpoint functions across 19 files (problems, groups,
  NIMBUS, XNIMBUS, SCORE-bands, GDM-SCORE-bands, GNIMBUS, EMO routes).
• Consolidated Orval-generated models and clients into a single file instead of
  splitting across src/lib/gen/models.
• Migrated all components['schemas'] references to direct $lib/gen/models
  imports.
• Refactored NIMBUS frontend to Orval handler pattern (removed +server.ts
  proxy, callNimbusAPI).
• Refactored GNIMBUS +server.ts from generic dispatch to individual Orval
  calls.
• Removed unused client files: client.ts, client-types.ts, zod-schemas.ts,
  zod-types.ts.
• Removed openapi-fetch and openapi-typescript-fetch dependencies.
• Renamed "Worsen until" to "Impair until" in NIMBUS constants.

Fixed

• Fixed Orval GET-with-body error (pass undefined instead of null for
  optional body params).
• Fixed stale Orval imports in E-NAUTILUS, problems/handler, and
  problems/define/handler.
• Fixed explanation bar chart / ranking bar chart label overflow (rotate,
  truncate, cap margins).

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Documentation

Added

• Added guide on how to implement method interfaces in the GUI.

Changed

• Updated contributing guide to include instructions for running tests without
  make.
• Updated installation documentation for DESDEO on JYU Windows.
• Fixed improperly formatted MkDocs settings for Read the Docs builds.
• Fixed broken cross-references in notebook markdown cells (autorefs to standard
  links).
• Completed sympy evaluator, Pyomo solvers, Nevergrad solver, and Summary of
  Solvers documentation sections.
• Made all documentation code cells executable with real test problems.
• Suppressed sklearn and COBYLA warnings in documentation notebooks.

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Rumor has it (automatically generated)

• Updated documentation for installing DESDEO by @juropo in #427
• Purging singleton request models and using query params instead by @PtrBednarik in #433
• New error page (without models) by @MajoMartinco in #444
• Head titles and descriptions by @MajoMartinco in #447
• Login form indicators by @MajoMartinco in #450

New Contributors

• @MajoMartinco made their first contribution in #444

Full Changelog: v2.2.2...v2.3.0