{"row":{"id":"ADR-086","title":"builtin Rams sweep · nika:csv_to_json → nika:convert universal multi-format · less but better","file":"adr-086-builtin-rams-sweep-convert-universal-multi-format.md","status":"accepted","date":"2026-05-27","cites":7,"supersedes":[],"superseded_by":[],"layers":["L0"],"tags":["nika-catalog","nika-schema","stdlib","builtins"],"room":true},"pin":{"release_tag":"v0.107.0","commit":"5d61b7e13f1f6a10c17414f61146648f76bcf2bd"}}

[{"k":"h","depth":1,"text":"ADR-086 · builtin Rams sweep · nika:csv_to_json → nika:convert","id":"adr-086--builtin-rams-sweep--nikacsv_to_json--nikaconvert"},{"k":"h","depth":2,"text":"Context","id":"context"},{"k":"p","inline":[{"k":"text","text":"Operator-led audit 2026-05-27 of the post-D-2026-05-22-N6 26-builtin\nset surfaced 4 high-confidence Rams « less but better » consolidation\ncandidates · the operator named "},{"k":"code","text":"nika:csv_to_json"},{"k":"text","text":" specifically as\nthe canonical anti-pattern (single-direction · single-format · vs\nthe "},{"k":"code","text":"fetch+extract"},{"k":"text","text":" super-powerful-with-mode-args canonical exemplar)."}]},{"k":"p","inline":[{"k":"text","text":"Operator verbatim · « faut vraiment réfléchir de manière plus\natomique · "},{"k":"code","text":"nika:csv_to_json"},{"k":"text","text":" faudrait plutôt un builtin super\npuissant qui gère à convertir n'importe quoi · le "},{"k":"code","text":"fetch"},{"k":"text","text":" il est\navancé avec extract · les autres ça devrait être pareil · faut pas\nhésiter à améliorer · réunir · Rams · et chercher les meilleurs\ncrates correspondant »."}]},{"k":"p","inline":[{"k":"text","text":"The D-N6 stdlib-collapse (42 → 27) + 2026-05-27 "},{"k":"code","text":"json_merge"},{"k":"text","text":" cut\n(27 → 26) established the precedent · the canonical pattern is « one\nsuper-powerful builtin · multi-mode parameters » (jq subsumes ~13\ndata builtins · fetch subsumes 8 extract modes). This ADR continues\nthe sweep at the format-conversion layer."}]},{"k":"h","depth":2,"text":"Decision","id":"decision"},{"k":"p","inline":[{"k":"code","text":"nika:csv_to_json"},{"k":"text","text":" removed · "},{"k":"code","text":"nika:convert"},{"k":"text","text":" adopted as universal\nmulti-format converter."}]},{"k":"h","depth":3,"text":"`nika:convert` surface","id":"nikaconvert-surface"},{"k":"code","lang":"yaml","text":"invoke:\n  tool: \"nika:convert\"\n  args:\n    input: \"\u0024{{ tasks.A.output }}\"   # data to convert\n    from: csv                         # REQUIRED · enum · json | yaml | toml | csv\n    to: json                          # REQUIRED · enum · json | yaml | toml | csv\n    has_header: true                  # OPTIONAL · CSV only · default true"},{"k":"h","depth":3,"text":"Formats v0.1 baseline","id":"formats-v01-baseline"},{"k":"p","inline":[{"k":"text","text":"4 formats · "},{"k":"code","text":"json"},{"k":"text","text":" · "},{"k":"code","text":"yaml"},{"k":"text","text":" · "},{"k":"code","text":"toml"},{"k":"text","text":" · "},{"k":"code","text":"csv"},{"k":"text","text":" · 12 directions in scope\n(4×3 minus identity). Forward-compat · "},{"k":"code","text":"xml"},{"k":"text","text":" · "},{"k":"code","text":"tsv"},{"k":"text","text":" · "},{"k":"code","text":"messagepack"},{"k":"text","text":"\netc. ADD on consumer signal per "},{"k":"code","text":"#[non_exhaustive]"},{"k":"text","text":" ratchet (additive\nMINOR per ADR-002 · amended D-2026-06-20-N1 · real semver toward 1.0)."}]},{"k":"h","depth":3,"text":"Engine catalog mutation","id":"engine-catalog-mutation"},{"k":"p","inline":[{"k":"code","text":"nika-catalog::ALL_BUILTINS"},{"k":"text","text":" (line ~21 in "},{"k":"code","text":"data/builtins.rs"},{"k":"text","text":") ·"}]},{"k":"list","ordered":false,"items":[[{"k":"text","text":"DELETE entry · "},{"k":"code","text":"Builtin { name: \"csv_to_json\", category: Data }"}],[{"k":"text","text":"INSERT entry (alphabetical · between "},{"k":"code","text":"assert"},{"k":"text","text":" and "},{"k":"code","text":"cost"},{"k":"text","text":") ·\n"},{"k":"code","text":"Builtin { name: \"convert\", category: Data }"}]]},{"k":"p","inline":[{"k":"text","text":"Sort invariant preserved · "},{"k":"code","text":"convert"},{"k":"text","text":" < "},{"k":"code","text":"cost"},{"k":"text","text":" alphabetically ("},{"k":"code","text":"c-o-n"},{"k":"text","text":"\n< "},{"k":"code","text":"c-o-s"},{"k":"text","text":"). The 6-existing tests ("},{"k":"code","text":"builtin_count"},{"k":"text","text":" · "},{"k":"code","text":"sorted_order"},{"k":"text","text":" ·\n"},{"k":"code","text":"find_known_builtins"},{"k":"text","text":" · "},{"k":"code","text":"is_known_builtin_works"},{"k":"text","text":" · "},{"k":"code","text":"case_sensitive"},{"k":"text","text":" ·\n"},{"k":"code","text":"all_builtins_have_non_empty_names"},{"k":"text","text":" · "},{"k":"code","text":"category_counts"},{"k":"text","text":") stay GREEN ·\ntotal 26 unchanged · 8 Data category unchanged."}]},{"k":"h","depth":3,"text":"Engine trust.rs mutation (per ADR-084 §C precedent)","id":"engine-trustrs-mutation-per-adr-084-c-precedent"},{"k":"p","inline":[{"k":"code","text":"TRUST_PROPAGATING_BUILTINS"},{"k":"text","text":" list ·"}]},{"k":"list","ordered":false,"items":[[{"k":"text","text":"DELETE "},{"k":"code","text":"\"nika:csv_to_json\""}],[{"k":"text","text":"INSERT "},{"k":"code","text":"\"nika:convert\""},{"k":"text","text":" (alphabetical · first slot)"}]]},{"k":"p","inline":[{"k":"text","text":"Trust class unchanged ("},{"k":"code","text":"csv_to_json"},{"k":"text","text":" was PROPAGATING · "},{"k":"code","text":"convert"},{"k":"text","text":" stays\nPROPAGATING · pure-data transform · output trust = input trust)."}]},{"k":"h","depth":3,"text":"Engine codegen.rs mutation (ADR-085 no-drift gate)","id":"engine-codegenrs-mutation-adr-085-no-drift-gate"},{"k":"p","inline":[{"k":"code","text":"enum_excludes_legacy_post_d_n6"},{"k":"text","text":" regression test extends the legacy\nexclusion list with "},{"k":"code","text":"nika:csv_to_json"},{"k":"text","text":" · 5 → 6 legacy names guarded\n(the cut-set regression)."}]},{"k":"h","depth":3,"text":"Spec mutation (companion · nika/spec submodule)","id":"spec-mutation-companion--nikaspec-submodule"},{"k":"p","inline":[{"k":"text","text":"Spec ratchet shipped same-arc per the operator-led Rams sweep ·"}]},{"k":"list","ordered":false,"items":[[{"k":"code","text":"nika/spec/stdlib/builtins-v0.1.md"},{"k":"text","text":" · §1 Data row + §3 Data section\nrename csv_to_json → convert with full new semantics (formats list ·\npattern rationale · reference implementation crates · alphabetical\nposition preserved in §3)."}],[{"k":"code","text":"nika/spec/schemas/workflow.schema.json"},{"k":"text","text":" · invoke.tool oneOf nika\nbranch enum · alphabetical re-sort (convert moves before cost) ·\ncount stays 26 · LSP-perfect autocomplete preserved."}]]},{"k":"h","depth":2,"text":"Reference implementation (L2 nika-builtin admission · future)","id":"reference-implementation-l2-nika-builtin-admission--future"},{"k":"p","inline":[{"k":"text","text":"Primary-source verified candidate crates (crates.io API · 2026-05-27) ·"}]},{"k":"list","ordered":false,"items":[[{"k":"text","text":"Crate · Version · Updated · Notes"}],[{"k":"text","text":"`serde-transcode` · 1.1.1 · 2021-07-10 · Canonical orchestrator · sfackler · 15M+ downloads · API-stable (COMPLETE not abandoned)"}],[{"k":"text","text":"`serde_json` · 1.0 · (already nika dep) · JSON · zero-add"}],[{"k":"text","text":"`serde_yaml_bw` · 2.5.6 · 2026-05-02 · YAML · modern + maintained · 133k downloads · 2026-current"}],[{"k":"text","text":"`toml` · 1.1.2 · 2026-04-01 · TOML · spec 1.1.0 compliant · active"}],[{"k":"text","text":"`csv` · 1.4.0 · 2025-10-17 · CSV · quoting-aware · active"}]]},{"k":"p","inline":[{"k":"text","text":"Cohérent internal NUKE-LEGACY Class 2 (git is the archive · zero\ndeprecation alias) · zero-add prefer when an existing dep covers\nthe case · "},{"k":"code","text":"serde_json"},{"k":"text","text":" already in workspace. New deps gated on the\nL2 nika-builtin admission ceremony per Diamond Rule 2 12-gate."}]},{"k":"h","depth":2,"text":"Consequences","id":"consequences"},{"k":"h","depth":3,"text":"Positive","id":"positive"},{"k":"list","ordered":false,"items":[[{"k":"strong","text":"Symmetry signal"},{"k":"text","text":" · per « less but better » Rams principle · the\nfetch+extract pattern · jq subsumption · convert · all the same\n« one super-powerful builtin · multi-mode args » canonical shape\napplied at 3 distinct layers (HTTP · data transform · format\nconversion). The pattern propagates the more it's applied · easier\ncognitive surface for cookbook authors + LSP consumers."}],[{"k":"strong","text":"Bidirectional coverage"},{"k":"text","text":" · "},{"k":"code","text":"nika:convert from:csv to:json"},{"k":"text","text":" AND\n"},{"k":"code","text":"nika:convert from:json to:csv"},{"k":"text","text":" (the latter previously covered only\nvia "},{"k":"code","text":"jq @csv"},{"k":"text","text":") · single canonical builtin · no « which direction\ngoes through which tool » mental load."}],[{"k":"strong","text":"Forward extensibility"},{"k":"text","text":" · "},{"k":"code","text":"xml"},{"k":"text","text":" · "},{"k":"code","text":"tsv"},{"k":"text","text":" · "},{"k":"code","text":"messagepack"},{"k":"text","text":" add via\nenum extension (forward-compat MINOR ratchet per ADR-002 · amended\nD-2026-06-20-N1 · zero new builtin slot consumed)."}],[{"k":"strong","text":"Trust class preserved"},{"k":"text","text":" · csv_to_json was PROPAGATING · convert\nstays PROPAGATING · zero security regression."}],[{"k":"strong","text":"No-drift gate enforced"},{"k":"text","text":" · ADR-085 codegen.rs test\n"},{"k":"code","text":"enum_matches_catalog_one_to_one"},{"k":"text","text":" AUTO-detects the spec ↔ engine\nparity · the rename propagates automatically once ALL_BUILTINS\nmutates · "},{"k":"code","text":"nika_builtin_tool_enum_schema()"},{"k":"text","text":" returns the new 26-set\nderived at call time."}]]},{"k":"h","depth":3,"text":"Negative","id":"negative"},{"k":"list","ordered":false,"items":[[{"k":"strong","text":"Public API breaking"},{"k":"text","text":" · existing workflows using "},{"k":"code","text":"tool: nika:csv_to_json"},{"k":"text","text":"\nwill fail to parse against the spec-26 closed enum + against\n"},{"k":"code","text":"is_known_builtin(\"csv_to_json\")"},{"k":"text","text":" in engine. Acceptable on forever-\nv0.x per ADR-002 (NUKE-LEGACY · git is the archive · zero deprecation\nalias per internal no-legacy doctrine)."},{"k":"text","text":"- Mitigation · the existing nika spec is pre-v1.0 GA · cookbook\n  authors haven't started migration · breakage cost ≈ 0 today.\n- Mitigation · the trust.rs test `legacy_builtins_unknown_post_d_n6`\n  explicitly catches any code path that still references\n  `\"nika:csv_to_json\"` · fails closed (uncategorized → Untrusted\n  output)."}]]},{"k":"h","depth":3,"text":"Neutral","id":"neutral"},{"k":"list","ordered":false,"items":[[{"k":"strong","text":"Tests · +1 net new legacy guard"},{"k":"text","text":" in codegen.rs · 8 conformance\ntests stay GREEN (6 from baseline + 2 spec-26 gates from ADR-084) ·\nlegacy exclusion list 5 → 6."}],[{"k":"strong","text":"L0 layer constraint preserved"},{"k":"text","text":" · the rename is pure data + pure\ntest mutation · zero I/O · zero async · zero L0 violation."}],[{"k":"strong","text":"Backward graph projection (TTL)"},{"k":"text","text":" · internal monorepo nika-\nlanguage graph carries 4 csv_to_json refs (instance · Builtin\nfamily member-list · "},{"k":"code","text":"raises"},{"k":"text","text":" arc · "},{"k":"code","text":"invokedBy"},{"k":"text","text":" arc) · these\nupdate SAME-ARC in the monorepo cascade (separate from this\nengine ADR)."}]]},{"k":"h","depth":2,"text":"Alternatives considered","id":"alternatives-considered"},{"k":"h","depth":3,"text":"A · Keep `nika:csv_to_json` · add `nika:yaml_to_json` · `nika:toml_to_json` · etc.","id":"a--keep-nikacsv_to_json--add-nikayaml_to_json--nikatoml_to_json--etc"},{"k":"p","inline":[{"k":"text","text":"REJECTED · N² builtin slot explosion · 4 formats × 3 target = 12\nbuiltins for what should be 1 · violates « less but better » Rams\nprinciple + the D-N6 anti-anti-pattern. Per existing spec comment\n« CSV parsing is not jq's job · the reverse direction is jq @csv » ·\nthe asymmetric treatment was exactly the friction the operator\naudit named."}]},{"k":"h","depth":3,"text":"B · Keep `csv_to_json` only · skip the Rams sweep","id":"b--keep-csv_to_json-only--skip-the-rams-sweep"},{"k":"p","inline":[{"k":"text","text":"REJECTED · operator-led directive (« FAIS · do it ») + the symmetry\nsignal (fetch+extract · jq · now convert · all the same « one\nsuper-powerful builtin · multi-mode args » pattern) · skipping leaves\nthe canonical anti-pattern in the spec."}]},{"k":"h","depth":3,"text":"C · Adopt `dasel` library or similar all-in-one Go-origin tool","id":"c--adopt-dasel-library-or-similar-all-in-one-go-origin-tool"},{"k":"p","inline":[{"k":"text","text":"REJECTED · "},{"k":"code","text":"dasel"},{"k":"text","text":" is a Go binary · embedding requires unsavory\nsubprocess shenanigans · violates L0 « zero I/O · zero async » +\nsovereignty Rule 1 + ADR-001 pure-Rust mandate. "},{"k":"code","text":"serde-transcode"},{"k":"text","text":" is\nthe canonical serde-ecosystem Rust solution · primary-source verified."}]},{"k":"h","depth":2,"text":"Gate verification","id":"gate-verification"},{"k":"p","inline":[{"k":"text","text":"Per ADR-084 precedent (data refactor not crate admission · 12-gate\nreduces to applicable gates) ·"}]},{"k":"list","ordered":false,"items":[[{"k":"text","text":"✅ Gate 2 TDD · trust.rs "},{"k":"code","text":"legacy_builtins_unknown_post_d_n6"},{"k":"text","text":" extended\n· codegen.rs "},{"k":"code","text":"enum_excludes_legacy_post_d_n6"},{"k":"text","text":" extended · existing\nbuiltins.rs "},{"k":"code","text":"category_counts"},{"k":"text","text":" (Data still 8) preserved · all GREEN."}],[{"k":"text","text":"✅ Gate 3 IMPL · "},{"k":"code","text":"cargo check --workspace"},{"k":"text","text":" GREEN."}],[{"k":"text","text":"✅ Gate 4 CLIPPY · "},{"k":"code","text":"cargo clippy --workspace --all-targets -- -D warnings"},{"k":"text","text":" 0 warnings."}],[{"k":"text","text":"✅ Gate 8 DOCS · "},{"k":"code","text":"cargo doc --no-deps -p nika-catalog -p nika-schema"},{"k":"text","text":"\n0 warnings."}],[{"k":"text","text":"✅ Gate 12 ATOMIC · single engine commit + single monorepo bump."}],[{"k":"code","text":"cargo fmt --check"},{"k":"text","text":" GREEN · "},{"k":"code","text":"cargo deny check"},{"k":"text","text":" ok."}],[{"k":"text","text":"Gates 1 / 5 / 6 / 7 / 9 / 10 / 11 · N/A for data refactor."}]]},{"k":"h","depth":2,"text":"Future Rams ratchets (trigger-gated · ADR-087+ reserved)","id":"future-rams-ratchets-trigger-gated--adr-087-reserved"},{"k":"p","inline":[{"k":"text","text":"3 remaining consolidation candidates from the operator audit ·\ntrigger-gated per LOCK-031 spirit · don't pre-build infra ·"}]},{"k":"list","ordered":true,"items":[[{"k":"strong","text":"`nika:wait`"},{"k":"text","text":" · collapse "},{"k":"code","text":"sleep"},{"k":"text","text":" + "},{"k":"code","text":"wait_until"},{"k":"text","text":" into one temporal\nprimitive with "},{"k":"code","text":"duration:"},{"k":"text","text":" OR "},{"k":"code","text":"until:"},{"k":"text","text":" mode. Net 26 → 25. Trigger ·\nD-lock + operator OUI/NON Bucket-C user-explicit-lock."}],[{"k":"strong","text":"`nika:inspect`"},{"k":"text","text":" · collapse 4 introspection builtins (cost ·\nrecords · dag_info · threads) into one with "},{"k":"code","text":"view:"},{"k":"text","text":" enum. Net 26 →"},{"k":"text","text":"23. Trigger · D-lock + workflow.schema.json oneOf-vs-untyped design\ndecision (return-shape heterogeneity)."}],[{"k":"strong","text":"`nika:json_diff` jq-subsume feasibility"},{"k":"text","text":" · jq CAN express\ndiff (recipe in audit doc §5) but loses the RFC-6902-canonical-Patch\noutput format. Trigger · cookbook adoption of the jq-diff recipe +\noperator preference signal."}]]},{"k":"p","inline":[{"k":"text","text":"When all 3 land · 26 → ~21 collapse · same "},{"k":"code","text":"nika: v1"},{"k":"text","text":" envelope ·\nreal-semver-toward-1.0 discipline (ADR-002 · amended D-2026-06-20-N1)."}]},{"k":"h","depth":2,"text":"Companion artefacts","id":"companion-artefacts"},{"k":"list","ordered":false,"items":[[{"k":"code","text":"nika-catalog/src/data/builtins.rs"},{"k":"text","text":" · ALL_BUILTINS rename (delete\ncsv_to_json · insert convert in alphabetical position)."}],[{"k":"code","text":"nika-schema/src/trust.rs"},{"k":"text","text":" · TRUST_PROPAGATING_BUILTINS rename +\n"},{"k":"code","text":"legacy_builtins_unknown_post_d_n6"},{"k":"text","text":" test extended (+csv_to_json)."}],[{"k":"code","text":"nika-schema/src/codegen.rs"},{"k":"text","text":" · "},{"k":"code","text":"enum_excludes_legacy_post_d_n6"},{"k":"text","text":"\ntest extended (+csv_to_json · 5 → 6 legacy guarded)."}],[{"k":"code","text":"nika/spec/stdlib/builtins-v0.1.md"},{"k":"text","text":" (separate submodule commit\n"},{"k":"code","text":"2a14540"},{"k":"text","text":") · csv_to_json section → convert section with universal\nmulti-format semantics."}],[{"k":"code","text":"nika/spec/schemas/workflow.schema.json"},{"k":"text","text":" (same submodule commit) ·\ninvoke.tool oneOf nika branch enum alphabetical re-sort."}],[{"k":"text","text":"Internal · Rams audit doc (private monorepo) · the 26-builtin\nbuiltin-by-builtin table + 4-collapse proposal + crate research +\nshipping plan."}]]},{"k":"h","depth":2,"text":"References","id":"references"},{"k":"list","ordered":false,"items":[[{"k":"text","text":"ADR-085 · spec workflow.schema.json oneOf bridge (prerequisite)"}],[{"k":"text","text":"ADR-084 · nika-catalog reconciliation to spec 26 (prerequisite)"}],[{"k":"text","text":"ADR-082 · envelope "},{"k":"code","text":"nika: v1"},{"k":"text","text":" single-version-marker"}],[{"k":"text","text":"D-2026-05-22-N6 · stdlib-collapse 42 → 27 (precedent · « one\nobvious way » + jq subsumption)"}],[{"k":"text","text":"2026-05-27 · "},{"k":"code","text":"nika:json_merge"},{"k":"text","text":" cut (precedent · razor-edge Rams\ndecision + jaq source-verified)"}],[{"k":"text","text":"Internal · "},{"k":"code","text":"no-legacy-no-back-compat.md"},{"k":"text","text":" Class 2 (git is the\narchive)"}],[{"k":"text","text":"Internal · LOCK-031 trigger-gated discipline (no infra behind\nlocked gate · future ratchet 1/2/3 deferred)"}],[{"k":"text","text":"Internal · "},{"k":"code","text":"cross-source-validation.md"},{"k":"text","text":" §2.6 Signal 7\n(verify-the-auditor · crate claims primary-source-verified via\ncrates.io API)"}]]},{"k":"p","inline":[{"k":"text","text":"🦋"}]}]

ADR-086

builtin Rams sweep · nika:csv_to_json → nika:convert universal multi-format · less but better

accepted · 2026-05-27 · L0 · cites 7

ADR-086 · builtin Rams sweep · nika:csv_to_json → nika:convert #

Context #

Operator-led audit 2026-05-27 of the post-D-2026-05-22-N6 26-builtin set surfaced 4 high-confidence Rams « less but better » consolidation candidates · the operator named nika:csv_to_json specifically as the canonical anti-pattern (single-direction · single-format · vs the fetch+extract super-powerful-with-mode-args canonical exemplar).

Operator verbatim · « faut vraiment réfléchir de manière plus atomique · nika:csv_to_json faudrait plutôt un builtin super puissant qui gère à convertir n'importe quoi · le fetch il est avancé avec extract · les autres ça devrait être pareil · faut pas hésiter à améliorer · réunir · Rams · et chercher les meilleurs crates correspondant ».

The D-N6 stdlib-collapse (42 → 27) + 2026-05-27 json_merge cut (27 → 26) established the precedent · the canonical pattern is « one super-powerful builtin · multi-mode parameters » (jq subsumes ~13 data builtins · fetch subsumes 8 extract modes). This ADR continues the sweep at the format-conversion layer.

Decision #

nika:csv_to_json removed · nika:convert adopted as universal multi-format converter.

`nika:convert` surface #

yaml

1◆invoke:2  tool: "nika:convert"3  args:4    input: "${{ tasks.A.output }}"   # data to convert5    from: csv                         # REQUIRED · enum · json | yaml | toml | csv6    to: json                          # REQUIRED · enum · json | yaml | toml | csv7    has_header: true                  # OPTIONAL · CSV only · default true

Formats v0.1 baseline #

4 formats · json · yaml · toml · csv · 12 directions in scope (4×3 minus identity). Forward-compat · xml · tsv · messagepack etc. ADD on consumer signal per #[non_exhaustive] ratchet (additive MINOR per ADR-002 · amended D-2026-06-20-N1 · real semver toward 1.0).

Engine catalog mutation #

nika-catalog::ALL_BUILTINS (line ~21 in data/builtins.rs) ·

DELETE entry · Builtin { name: "csv_to_json", category: Data }
INSERT entry (alphabetical · between assert and cost) · Builtin { name: "convert", category: Data }

Sort invariant preserved · convert < cost alphabetically (c-o-n < c-o-s). The 6-existing tests (builtin_count · sorted_order · find_known_builtins · is_known_builtin_works · case_sensitive · all_builtins_have_non_empty_names · category_counts) stay GREEN · total 26 unchanged · 8 Data category unchanged.

Engine trust.rs mutation (per ADR-084 §C precedent) #

TRUST_PROPAGATING_BUILTINS list ·

DELETE "nika:csv_to_json"
INSERT "nika:convert" (alphabetical · first slot)

Trust class unchanged (csv_to_json was PROPAGATING · convert stays PROPAGATING · pure-data transform · output trust = input trust).

Engine codegen.rs mutation (ADR-085 no-drift gate) #

enum_excludes_legacy_post_d_n6 regression test extends the legacy exclusion list with nika:csv_to_json · 5 → 6 legacy names guarded (the cut-set regression).

Spec mutation (companion · nika/spec submodule) #

Spec ratchet shipped same-arc per the operator-led Rams sweep ·

nika/spec/stdlib/builtins-v0.1.md · §1 Data row + §3 Data section rename csv_to_json → convert with full new semantics (formats list · pattern rationale · reference implementation crates · alphabetical position preserved in §3).
nika/spec/schemas/workflow.schema.json · invoke.tool oneOf nika branch enum · alphabetical re-sort (convert moves before cost) · count stays 26 · LSP-perfect autocomplete preserved.

Reference implementation (L2 nika-builtin admission · future) #

Primary-source verified candidate crates (crates.io API · 2026-05-27) ·

Crate · Version · Updated · Notes
`serde-transcode` · 1.1.1 · 2021-07-10 · Canonical orchestrator · sfackler · 15M+ downloads · API-stable (COMPLETE not abandoned)
`serde_json` · 1.0 · (already nika dep) · JSON · zero-add
`serde_yaml_bw` · 2.5.6 · 2026-05-02 · YAML · modern + maintained · 133k downloads · 2026-current
`toml` · 1.1.2 · 2026-04-01 · TOML · spec 1.1.0 compliant · active
`csv` · 1.4.0 · 2025-10-17 · CSV · quoting-aware · active

Cohérent internal NUKE-LEGACY Class 2 (git is the archive · zero deprecation alias) · zero-add prefer when an existing dep covers the case · serde_json already in workspace. New deps gated on the L2 nika-builtin admission ceremony per Diamond Rule 2 12-gate.

Consequences #

Positive #

Symmetry signal · per « less but better » Rams principle · the fetch+extract pattern · jq subsumption · convert · all the same « one super-powerful builtin · multi-mode args » canonical shape applied at 3 distinct layers (HTTP · data transform · format conversion). The pattern propagates the more it's applied · easier cognitive surface for cookbook authors + LSP consumers.
Bidirectional coverage · nika:convert from:csv to:json AND nika:convert from:json to:csv (the latter previously covered only via jq @csv) · single canonical builtin · no « which direction goes through which tool » mental load.
Forward extensibility · xml · tsv · messagepack add via enum extension (forward-compat MINOR ratchet per ADR-002 · amended D-2026-06-20-N1 · zero new builtin slot consumed).
Trust class preserved · csv_to_json was PROPAGATING · convert stays PROPAGATING · zero security regression.
No-drift gate enforced · ADR-085 codegen.rs test enum_matches_catalog_one_to_one AUTO-detects the spec ↔ engine parity · the rename propagates automatically once ALL_BUILTINS mutates · nika_builtin_tool_enum_schema() returns the new 26-set derived at call time.

Negative #

Public API breaking · existing workflows using tool: nika:csv_to_json will fail to parse against the spec-26 closed enum + against is_known_builtin("csv_to_json") in engine. Acceptable on forever- v0.x per ADR-002 (NUKE-LEGACY · git is the archive · zero deprecation alias per internal no-legacy doctrine).- Mitigation · the existing nika spec is pre-v1.0 GA · cookbook authors haven't started migration · breakage cost ≈ 0 today. - Mitigation · the trust.rs test `legacy_builtins_unknown_post_d_n6` explicitly catches any code path that still references `"nika:csv_to_json"` · fails closed (uncategorized → Untrusted output).

Neutral #

Tests · +1 net new legacy guard in codegen.rs · 8 conformance tests stay GREEN (6 from baseline + 2 spec-26 gates from ADR-084) · legacy exclusion list 5 → 6.
L0 layer constraint preserved · the rename is pure data + pure test mutation · zero I/O · zero async · zero L0 violation.
Backward graph projection (TTL) · internal monorepo nika- language graph carries 4 csv_to_json refs (instance · Builtin family member-list · raises arc · invokedBy arc) · these update SAME-ARC in the monorepo cascade (separate from this engine ADR).

Alternatives considered #

A · Keep `nika:csv_to_json` · add `nika:yaml_to_json` · `nika:toml_to_json` · etc. #

REJECTED · N² builtin slot explosion · 4 formats × 3 target = 12 builtins for what should be 1 · violates « less but better » Rams principle + the D-N6 anti-anti-pattern. Per existing spec comment « CSV parsing is not jq's job · the reverse direction is jq @csv » · the asymmetric treatment was exactly the friction the operator audit named.

B · Keep `csv_to_json` only · skip the Rams sweep #

REJECTED · operator-led directive (« FAIS · do it ») + the symmetry signal (fetch+extract · jq · now convert · all the same « one super-powerful builtin · multi-mode args » pattern) · skipping leaves the canonical anti-pattern in the spec.

C · Adopt `dasel` library or similar all-in-one Go-origin tool #

REJECTED · dasel is a Go binary · embedding requires unsavory subprocess shenanigans · violates L0 « zero I/O · zero async » + sovereignty Rule 1 + ADR-001 pure-Rust mandate. serde-transcode is the canonical serde-ecosystem Rust solution · primary-source verified.

Gate verification #

Per ADR-084 precedent (data refactor not crate admission · 12-gate reduces to applicable gates) ·

✅ Gate 2 TDD · trust.rs legacy_builtins_unknown_post_d_n6 extended · codegen.rs enum_excludes_legacy_post_d_n6 extended · existing builtins.rs category_counts (Data still 8) preserved · all GREEN.
✅ Gate 3 IMPL · cargo check --workspace GREEN.
✅ Gate 4 CLIPPY · cargo clippy --workspace --all-targets -- -D warnings 0 warnings.
✅ Gate 8 DOCS · cargo doc --no-deps -p nika-catalog -p nika-schema 0 warnings.
✅ Gate 12 ATOMIC · single engine commit + single monorepo bump.
cargo fmt --check GREEN · cargo deny check ok.
Gates 1 / 5 / 6 / 7 / 9 / 10 / 11 · N/A for data refactor.

Future Rams ratchets (trigger-gated · ADR-087+ reserved) #

3 remaining consolidation candidates from the operator audit · trigger-gated per LOCK-031 spirit · don't pre-build infra ·

`nika:wait` · collapse sleep + wait_until into one temporal primitive with duration: OR until: mode. Net 26 → 25. Trigger · D-lock + operator OUI/NON Bucket-C user-explicit-lock.
`nika:inspect` · collapse 4 introspection builtins (cost · records · dag_info · threads) into one with view: enum. Net 26 →23. Trigger · D-lock + workflow.schema.json oneOf-vs-untyped design decision (return-shape heterogeneity).
`nika:json_diff` jq-subsume feasibility · jq CAN express diff (recipe in audit doc §5) but loses the RFC-6902-canonical-Patch output format. Trigger · cookbook adoption of the jq-diff recipe + operator preference signal.

When all 3 land · 26 → ~21 collapse · same nika: v1 envelope · real-semver-toward-1.0 discipline (ADR-002 · amended D-2026-06-20-N1).

Companion artefacts #

nika-catalog/src/data/builtins.rs · ALL_BUILTINS rename (delete csv_to_json · insert convert in alphabetical position).
nika-schema/src/trust.rs · TRUST_PROPAGATING_BUILTINS rename + legacy_builtins_unknown_post_d_n6 test extended (+csv_to_json).
nika-schema/src/codegen.rs · enum_excludes_legacy_post_d_n6 test extended (+csv_to_json · 5 → 6 legacy guarded).
nika/spec/stdlib/builtins-v0.1.md (separate submodule commit 2a14540) · csv_to_json section → convert section with universal multi-format semantics.
nika/spec/schemas/workflow.schema.json (same submodule commit) · invoke.tool oneOf nika branch enum alphabetical re-sort.
Internal · Rams audit doc (private monorepo) · the 26-builtin builtin-by-builtin table + 4-collapse proposal + crate research + shipping plan.

References #

ADR-085 · spec workflow.schema.json oneOf bridge (prerequisite)
ADR-084 · nika-catalog reconciliation to spec 26 (prerequisite)
ADR-082 · envelope nika: v1 single-version-marker
D-2026-05-22-N6 · stdlib-collapse 42 → 27 (precedent · « one obvious way » + jq subsumption)
2026-05-27 · nika:json_merge cut (precedent · razor-edge Rams decision + jaq source-verified)
Internal · no-legacy-no-back-compat.md Class 2 (git is the archive)
Internal · LOCK-031 trigger-gated discipline (no infra behind locked gate · future ratchet 1/2/3 deferred)
Internal · cross-source-validation.md §2.6 Signal 7 (verify-the-auditor · crate claims primary-source-verified via crates.io API)

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read at v0.107.0 · the decision record ships with the engine

Every decision, with its status This one in the repo