Changelog

[0.7.1] - 2026-10-20

Bug Fixes

• Recover and document 0.7.0 publication (3d9f83d)

Documentation

• Rename CLAUDE.md to AGENTS.md to manage codex as well (44cfd0c)
• Move consumer guides from Outcome to flow (7db7e59)

Features

• Close agentic safety holes in flow typing and add result-usage checks (1202b41)

• CI now commits verified publication receipts to main automatically; the artifact remains available for manual recovery.

Other

• Merge pull request #23 from pencroff-lab/fix/publication-bun (3eae79c)
• Merge pull request #24 from pencroff-lab/fix/publication-bun (e6122b5)

Breaking changes and migration

v0.7.1 tightens the flow type contracts. Although this release uses a patch version, the following previously accepted TypeScript calls must migrate.

Validate untyped values at an adapter boundary

Fallible callbacks, pipeline stages and sources now reject visible inferred any and Promise<any>. Replace attempt(() => JSON.parse(raw)) with attemptValue, then validate its unknown payload. The adapters always add a success envelope, so parsed tuple-shaped or error-shaped data stays data.

import {
	attemptValue, attemptValueAsync, fail, flatMap, ok, type ResultTuple,
} from "@pencroff-lab/kore";

function parsePort(raw: string): ResultTuple<number> {
	return flatMap(attemptValue(() => JSON.parse(raw)), (data) => {
		if (
			typeof data !== "object" || data === null ||
			!("port" in data) || typeof data.port !== "number"
		) {
			return fail("numeric port required", "CONFIG:PORT");
		}
		return ok(data.port);
	});
}

function readResponse(response: Response): Promise<ResultTuple<unknown>> {
	return attemptValueAsync(() => response.json());
}

attemptValue rejects known Promise/PromiseLike returns, including mixed value-or-promise returns. Use attemptValueAsync for them; it awaits thenables and converts rejections to failures. Validate the resulting payload before reading its properties, as in parsePort above.

Explicit success type arguments remain a guard bypass: attempt<number>(() => JSON.parse(raw)) still compiles. Preannotated callbacks, operator aliases and casts can also erase the raw return type; JavaScript has no type protection. Consumers need type-aware unsafe-any lint for returns, assignments, arguments, member access and calls. An explicit generic is a type claim, not data validation.

Split pipelines longer than ten stages

The widening overloads are removed. pipe and pipeAsync now reject an eleventh stage; compose typed chunks instead.

import { ok, onOk, pipe, type ResultTuple } from "@pencroff-lab/kore";

const step = onOk((n: number) => ok(n + 1));
const first = pipe(
	ok(0), step, step, step, step, step, step, step, step, step, step,
);
const result: ResultTuple<number> = pipe(first, step);

For async chunks, await the first pipeAsync result or pass its promise as the source of the next pipeAsync call.

Make side-effect returns explicit

effect accepts only void/undefined callbacks. It now rejects tuple returns, async callbacks, and expression-bodied value returns such as () => seen.push(1) (which returns a number). Use a block with no return for synchronous void work:

import { effect, ok } from "@pencroff-lab/kore";

const seen: number[] = [];
const recorded = effect(ok(1), () => {
	seen.push(1);
});

Use flatMap/flatMapAsync for fallible work, preserving the original value with map if needed. Use effectAsync and await it for asynchronous void work.

import {
	effectAsync, flatMap, flatMapAsync, map, ok, type ResultTuple,
} from "@pencroff-lab/kore";

declare function save(n: number): ResultTuple<void>;
declare function saveAsync(n: number): Promise<ResultTuple<void>>;
declare function notify(): Promise<void>;

const saved = flatMap(ok(1), (n) => map(save(n), () => n));
const savedAsync = await flatMapAsync(ok(1), async (n) =>
	map(await saveAsync(n), () => n),
);
const notified = await effectAsync(ok(1), async () => {
	await notify();
});

Handle every result

Enable noFloatingPromises, and handle or propagate every tuple, including awaited results. Promise lint alone permits awaited or explicitly voided tuples to be discarded. v0.7.1 adds an in-repository tuple usage checker and Biome promise checks to local lint and CI; it ships no downstream tuple must-use rule. Consumer rule delivery remains a follow-up. These checks do not prove that every later caller handles an assigned or passed result.

[0.7.0] - 2026-09-11

Bug Fixes

• Compare file contents instead of timestamps (26477e4)

Documentation

• Doc(site): add custom CSS assets for site palette (05afc13)

Features

• Feat(flow): functional tuple based err boundaries (e65878e)

Other

• Re-works started (da571f6)
• Add docs by hextra (82b32fb)
• Update CHANGELOG.md (d9f1aa1)
• Update ci.yml (ed2b033)

Refactor

• Update protocol docs & tests (795b410)

[0.6.0] - 2026-09-01

Features

• Reject invalid callback returns (2887ef2)
• Add flatMap, deprecate unit (5c7a4dc)
• Add metadata immutability support (811fc20)
• Add flatMap and metadata immutability (d93e698)

Other

• Merge pull request #18 from pencroff-lab/17-fix-from-callback-various-values (fbc581f)

[0.5.0] - 2026-05-11

Features

• Check for any code in error tree (0247f5f)
• Allow hasCode() to check any code (d256835)

Other

• Merge pull request #16 from pencroff-lab/15-code-check—make-code-optional (4623e59)

[0.4.0] - 2026-04-02

Bug Fixes

• Capture native Error .code (4f7505a)

Documentation

• Replace Err.aggregate with Err.from (499adea)
• Update error handling patterns guide (dbb1155)

Features

• Refactor static wrap/aggregate, simplify API (b779e69)

Other

• Merge pull request #13 from pencroff-lab/12-native-err-code-capture (68d7a2d)
• Update package.json version (1c1132d)
• Merge pull request #14 from pencroff-lab/12-native-err-code-capture (53c44d2)

Refactor

• Use addAll for outcome error aggregation (64255f4)
• Simplify aggregation API (86127e3)

[0.3.1] - 2026-03-19

Documentation

• Rename and reorganize guide files in documentation (d8a7447)
• Update error handling guide link to reflect new naming convention (7220943)

Other

• Merge pull request #11 from pencroff-lab/docs_refactoring (49d81d0)

[0.3.0] - 2026-03-17

Bug Fixes

• Resolve lint warnings and type errors in test files (9484b3b)
• Use relative links in TypeDoc and plain @see references (7addecf)
• Add example test links in generated docs with relative paths (74a4e4b)

Documentation

• Add plan for Err metadata methods (f639b90)
• Add Git Worktree Guide (2d2e61a)
• Remove metadata-methods plan file (990251a)
• Add migration plan (a2423d8)
• Update API docs with example references (e5a22d2)
• Update JSDoc and TypeDoc guidelines (087816f)
• Add docs migration step 2 plan (7c0c40a)
• Update docs for types and utils (f485b31)
• Add @module tags for err and outcome (300b745)
• Enforce no file-level JSDoc in *.types.ts (585f3ba)
• Add migration plan for docs step 3 (ae81358)
• Add error handling and migration guides (118a7e3)
• Remove legacy migration plan files (6ae0896)

Features

• Add git-cliff (0dbef87)
• Add git-cliff changelog (452f121)
• DtStamp accept unix timestamps (f0da2ae)

Other

• Merge pull request #6 from pencroff-lab/set_changelog (0209fef)
• Merge pull request #7 from pencroff-lab/2-add-to-dtstamp-support-timestamp-as-number (12a9128)
• Haiku implementation (5c6b062)
• Add metadata find/filter tests for Err (96b1210)
• Merge branch ‘compare/haiku’ into 5-methods-metadata (bcddf35)
• Merge pull request #9 from pencroff-lab/5-methods-metadata (2a26fd7)
• Phase 1 - CI enforcement script of doc migration (ba78766)
• Phase 2 - Extract types of doc migration (3c7d7e6)
• Phase 3 - Create examples test files of doc migration (2c826e4)
• Phase 4 - Trim JSDoc in source files of doc migration (dc1c7c6)
• Phase 5 - Update CLAUDE.md of doc migration (dfe815c)
• Phase 6 - Verify and format of doc migration (d115a06)
• Merge pull request #10 from pencroff-lab/8-refine-doc-approach (063e378)

Refactor

• Inline dtStamp date init (7a7467d)

[0.2.1] - 2026-02-27

Other

• Add TypeDoc markdown API docs and config (ee2e861)
• Add TypeDoc JSDoc guide for API documentation conventions (32cb342)
• Add documentation guide and docstring audit reports to docs (191942d)
• Update Outcome API doc mismatch table with proposed fixes (056a91d)
• Add JSDoc comments for internal helpers in logger and outcome (16cbfd8)
• Update README links and remove obsolete API docs (9138bc7)
• Update package.json (9000041)
• Merge pull request #3 from pencroff-lab/TypeDoc_setup (15c4f97)

[0.2.0] - 2026-02-21

Other

• Add brainstorm and logger redesign documentation for zero-dependency logger implementation (fd2bf25)
• Add logger export and enhance test coverage with detailed argument resolution and context handling (afe06a9)
• Add logging guide with patterns, conventions, and integration details (caa26e0)
• Add logger documentation with usage patterns, types, and integration details (1b62c18)
• Bump version to 0.2.0 - logger with docs and guide (00b62ec)

[0.1.2] - 2026-02-19

Other

• Initial commit (170dd36)
• Initialize project with CI configuration, package setup, and TypeScript support (7121398)
• Add initial implementation of formatDateTime function and tests for Err and Outcome types (0e348af)
• Add testing guide and CLAUDE documentation for project setup and best practices (6238456)
• Add dtStamp function with options for formatting date and time, and update CI configuration for linting and test coverage (10a744d)
• Update linting scripts in package.json to include type checking and improve CI configuration (4e86b9b)
• Add scripts for version checking, build verification, and CJS compatibility (c4d21b6)
• Add README.md with library overview, installation instructions, API documentation, and development guidelines (c7b867f)
• Update CI configuration to add permissions for OIDC and increment package version to 0.1.1 (5079f66)
• Update CI configuration to uncomment permissions for OIDC and enable npm token usage (93273e3)
• Add llms.txt with library overview, modules, quick start, and installation instructions (2f0fdc8)