osspkg · markus621 · Sep 27, 2026 · Sep 27, 2026 · Sep 27, 2026 · Sep 27, 2026
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -1,23 +1,22 @@
-
 name: CI
 
 on:
   push:
-    branches: [ master ]
+    branches: [master]
   pull_request:
-    branches: [ master ]
+    branches: [master]
 
 jobs:
   build:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        go: [ '1.24' ]
+        go: ["1.26"]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v7
 
       - name: Setup Go
-        uses: actions/setup-go@v3
+        uses: actions/setup-go@v7
         with:
           go-version: ${{ matrix.go }}
 

diff --git a/.golangci.yml b/.golangci.yml
@@ -1,9 +1,9 @@
 version: "2"
 
 run:
-  go: "1.24"
+  go: "1.26"
   timeout: 5m
-  tests: false
+  tests: true
   issues-exit-code: 1
   modules-download-mode: readonly
   allow-parallel-runners: true
@@ -12,7 +12,7 @@ issues:
   max-issues-per-linter: 0
   max-same-issues: 0
   new: false
-  fix: false
+  fix: true
 
 output:
   formats:
@@ -27,6 +27,7 @@ formatters:
   enable:
     - gofmt
     - goimports
+    - gofumpt
 
 linters:
   settings:
@@ -46,7 +47,160 @@ linters:
         - G306
         - G501
         - G505
+    tagliatelle:
+      case:
+        rules:
+          json: snake # JSON: snake_case (user_id)
+          yaml: snake # YAML: snake_case
+          xml: camel # XML: camelCase
+          mapstructure: snake # mapstructure: snake_case
+          env: upperSnake # ENV: UPPER_SNAKE_CASE
+    varnamelen:
+      min-name-length: 2 # Минимальная длина имени
+      max-distance: 5 # i, j, k допустимы в scope <= 5 строк
+      ignore-names:
+        - err # err — идиоматично
+        - ok # ok — идиоматично
+        - id # id — часто используется
+        - db # db — часто используется
+        - tx # tx — транзакция
+        - wg # wg — WaitGroup
+        - mu # mu — mutex
+        - rw # rw — RWMutex
+        - ch # ch — channel
+        - fn # fn — function
+        - sb # sb — strings.Builder
+        - ctx # ctx — context
+        - q # q — querier
+        - r # r — repo / reader
+        - s # s — strategy / service
+        - f # f — filter
+        - a # a — left operand (сравнение)
+        - b # b — right operand (сравнение)
+      ignore-type-assert-ok: true # Игнорировать v, ok := x.(T)
+      ignore-map-index-ok: true # Игнорировать v, ok := m[k]
+      ignore-chan-recv-ok: true # Игнорировать v, ok := <-ch
+      ignore-decls:
+        - i int # for i := ...
+        - j int # вложенные циклы
+        - n int # количество
+        - t testing.T # тесты
+        - b testing.B # бенчмарки
+        - r *http.Request # HTTP handler
+        - w http.ResponseWriter # HTTP handler
+        - c *gin.Context # Gin context
+        - c echo.Context # Echo context
+        - s *Server # конструктор Server
+        - m *metrics # конструктор metrics
+    revive:
+      severity: warning
+      rules:
+        # -------------------------------------------------------------------------
+        # Предотвращение багов
+        # -------------------------------------------------------------------------
+        - name: atomic # Проверяет правильное использование sync/atomic
+        - name: range-val-in-closure # Захват переменной цикла в замыкании
+        - name: range-val-address # Взятие адреса переменной цикла
+        - name: unreachable-code # Недостижимый код после return/panic
+        - name: unchecked-type-assertion # Type assertion без проверки ok
+        - name: datarace # Потенциальные data races
+        - name: identical-branches # Одинаковые ветки if/else
+        - name: defer # Проблемы с defer (в циклах, результат)
+        - name: call-to-gc # Явные вызовы runtime.GC()
+        - name: waitgroup-by-value # WaitGroup передан по значению
+
+        # -------------------------------------------------------------------------
+        # Обработка ошибок — Go proverb: "Don't just check errors, handle them gracefully"
+        # -------------------------------------------------------------------------
+        - name: error-strings # Ошибки не должны начинаться с большой буквы
+        - name: error-return # error должен быть последним возвращаемым значением
+        - name: errorf # Использовать fmt.Errorf вместо errors.New + fmt.Sprintf
+        - name: unhandled-error # Необработанные ошибки
+          arguments:
+            - "fmt.Print"
+            - "fmt.Printf"
+            - "fmt.Println"
+
+        # -------------------------------------------------------------------------
+        # Сложность — Go proverb: "Clear is better than clever"
+        # -------------------------------------------------------------------------
+        - name: cognitive-complexity
+          arguments: [15] # Cognitive complexity <= 15
+        - name: cyclomatic
+          arguments: [10] # Cyclomatic complexity <= 10
+        - name: function-result-limit
+          arguments: [3] # Максимум 3 возвращаемых значения
+        - name: argument-limit
+          arguments: [5] # Максимум 5 аргументов функции
+
+        # -------------------------------------------------------------------------
+        # Чистота кода — Go proverb: "A little copying is better than a little dependency"
+        # -------------------------------------------------------------------------
+        - name: indent-error-flow # if err != nil { return } вместо else
+        - name: early-return # Ранний возврат вместо вложенности
+        - name: superfluous-else # Лишний else после return
+        - name: if-return # Упрощение if/return
+        - name: empty-block # Пустые блоки кода
+        - name: unnecessary-stmt # Ненужные операторы
+        - name: redundant-import-alias # import pkg "pkg" — лишний алиас
+        - name: confusing-results # Запутанные возвращаемые значения
+        - name: bool-literal-in-expr # if x == true → if x
+        - name: constant-logical-expr # Константные логические выражения
+        - name: modifies-parameter # Модификация параметров функции
+        - name: modifies-value-receiver # Модификация value receiver (бесполезно)
+        - name: redefines-builtin-id # Переопределение встроенных идентификаторов
+        - name: string-of-int # string(int) — частая ошибка
+        - name: time-equal # time.Time сравнение через ==
+        - name: unconditional-recursion # Безусловная рекурсия (бесконечный цикл)
+        - name: useless-break # break в конце case (Go делает это автоматически)
+
+        # -------------------------------------------------------------------------
+        # Хорошие практики — Go proverbs
+        # -------------------------------------------------------------------------
+        - name: context-as-argument # context.Context первым аргументом
+        - name: context-keys-type # Ключи контекста должны быть типизированы
+        - name: var-declaration # var x = 1 → x := 1
+        - name: blank-imports # Запрет blank imports кроме main/test
+        - name: dot-imports # Запрет dot imports
+        - name: unexported-return # Публичная функция возвращает приватный тип
+        - name: exported # Экспортируемые идентификаторы должны быть задокументированы
+          arguments:
+            - "checkPrivateReceivers"
+            - "disableStutteringCheck"
+
+        # -------------------------------------------------------------------------
+        # Именование — Go proverb: "Good naming is like good coding: concise"
+        # -------------------------------------------------------------------------
+        - name: var-naming
+          arguments:
+            - [
+                "ID",
+                "URL",
+                "API",
+                "HTTP",
+                "JSON",
+                "XML",
+                "DB",
+                "SQL",
+                "UUID",
+                "UID",
+                "GUID",
+                "TTL",
+                "TCP",
+                "UDP",
+                "IP",
+                "RPC",
+                "QPS",
+                "EOF",
+              ]
+        - name: package-comments # Пакеты должны иметь комментарии
+        - name: receiver-naming # Имена receiver (r, s, c, не this/self)
   exclusions:
+    rules:
+      - path: pki/internal/xocsp/ocsp.go
+        linters:
+          - revive
+          - nestif
     paths:
       - vendors/
   default: none
@@ -66,3 +220,39 @@ linters:
     - errorlint
     - bodyclose
     - gosec
+    - nilerr
+    - nilnesserr
+    - nilnil
+    - bidichk
+    - contextcheck
+    - fatcontext
+    - makezero
+    - forcetypeassert
+    - unconvert
+    - copyloopvar
+    - prealloc
+    - perfsprint
+    - gocritic
+    - goconst
+    - mnd
+    - revive
+    - predeclared
+    - reassign
+    - recvcheck
+    - asciicheck
+    - importas
+    - durationcheck
+    - tparallel
+    - thelper
+    - usetesting
+    - musttag
+    - errchkjson
+    - tagalign
+    - usestdlibvars
+    - nestif
+    - mirror
+    - whitespace
+    - decorder
+    - nonamedreturns
+    - inamedparam
+    - testpackage
diff --git a/.lic.yaml b/.lic.yaml
@@ -1,3 +1,3 @@
-author: Mikhail Knyazhev <markus621@yandex.ru>
+author: Mikhail Knyazhev <markus621@yandex.com>
 lic_short: "BSD 3-Clause"
 lic_file: LICENSE
diff --git a/AGENTS.md b/AGENTS.md
@@ -0,0 +1,25 @@
+# Agent instructions
+
+## Project
+
+- This repository is the Go module `go.osspkg.com/errors`, a single package at the repository root. It targets Go 1.26.
+- Keep the public error API compatible. `Trace` is exported; `Wrap` with multiple inputs must preserve each input for standard `errors.Is` and `errors.As` while retaining the colon-separated error text and legacy `Cause` behavior.
+- Tests for the public API use the external package `errors_test`.
+
+## Commands
+
+Run commands from the repository root.
+
+- `make lint` runs `goppy lint`, which performs Go module tidy/download and formatting before `golangci-lint` and `govulncheck`. It can change files; inspect `git status` and the diff afterward.
+- `make tests` runs `goppy test`.
+- `make build` runs `goppy build --arch=amd64`.
+- CI runs `make ci`. This target also installs `goppy@latest`, runs `goppy setup-lib` and the license target, then lint, tests, and build. Use it when the full CI sequence and local setup are intended.
+
+## Project memory
+
+For non-trivial work, use the Chroma collection `chat_go-errors_memory`:
+
+1. Ensure the collection exists before reading or writing. If missing, list collections and create this exact collection with the default embedding configuration.
+2. Query it with a concise semantic description of the current task before making design decisions.
+3. After the work, add a concise document only for a durable project decision or lesson. Query related memories first and update an existing document instead of duplicating it.
+4. Never store secrets, transcripts, or temporary command output. Memory supplements the current source and tests; it does not override them.
diff --git a/LICENSE b/LICENSE
@@ -1,6 +1,6 @@
 BSD 3-Clause License
 
-Copyright (c) 2024-2025, Mikhail Knyazhev <markus621@yandex.ru>
+Copyright (c) 2024-2026, Mikhail Knyazhev <markus621@yandex.com>
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:

diff --git a/Makefile b/Makefile
@@ -4,7 +4,7 @@ SHELL=/bin/bash
 
 .PHONY: install
 install:
-	go install go.osspkg.com/goppy/v2/cmd/goppy@latest
+	go install go.osspkg.com/goppy/v3/cmd/goppy@latest
 	goppy setup-lib
 
 .PHONY: lint

diff --git a/README.md b/README.md
@@ -1 +1,67 @@
-# go-errors
+# go-errors
+
+[![CI](https://github.com/osspkg/go-errors/actions/workflows/ci.yml/badge.svg)](https://github.com/osspkg/go-errors/actions/workflows/ci.yml)
+
+A small Go library for creating errors, adding context, retaining causes, and inspecting error chains. It has no third-party runtime dependencies and requires Go 1.26 or newer.
+
+## Installation
+
+```sh
+go get go.osspkg.com/errors
+```
+
+## Quick start
+
+```go
+package main
+
+import (
+	"errors"
+	"fmt"
+
+	errpkg "go.osspkg.com/errors"
+)
+
+var errConnectionRefused = errors.New("connection refused")
+
+func main() {
+	err := errpkg.Wrapf(errConnectionRefused, "dial %s", "db.example:5432")
+	if errors.Is(err, errConnectionRefused) {
+		fmt.Println(err)
+	}
+}
+```
+
+## API
+
+| API | Purpose |
+| --- | --- |
+| `New(message string) error` | Creates an error with a message. |
+| `Wrapf(cause error, message string, args ...any) error` | Adds formatted context to one cause; returns `nil` when `cause` is `nil`. |
+| `Wrap(errors ...error) error` | Combines non-nil errors, joining their messages with `: `. Every input remains discoverable through `errors.Is` and `errors.As`; returns `nil` if there are no non-nil inputs. |
+| `Trace(cause error, message string, args ...any) error` | Adds formatted context and a runtime stack trace; returns `nil` when `cause` is `nil`. |
+| `Queue(calls ...func() error) error` | Calls functions in order and returns the first error, or `nil` if all succeed. Callbacks must be non-nil. |
+| `Unwrap(err error) error` | Returns one underlying error from an `Unwrapper`; returns `nil` for nil errors and multi-cause errors. |
+| `Cause(err error) error` | Follows the legacy `Cause() error` chain and returns its terminal error. |
+| `Is(err, target error) bool` | Reports whether `err` or an error in its chain matches `target`. |
+| `As(err error, target any) bool` | Finds the first error in the chain assignable to `target`, following the standard `errors.As` contract. |
+| `Causer` | Interface for errors exposing `Cause() error`. |
+| `Unwrapper` | Interface for errors exposing `Unwrap() error`. |
+
+`Cause` follows legacy `Cause()` methods; it does not walk standard-library `%w` wrappers. Use `Is` or `As` to inspect those chains. For a `Wrap` call with several errors, `Cause` retains its legacy behavior and returns the final input, while `Is` and `As` inspect all inputs.
+
+## Development
+
+The repository uses Go 1.26 and `goppy` for its Makefile targets.
+
+```sh
+make lint
+make tests
+make build
+```
+
+CI runs `make ci`, which installs `goppy@latest`, runs `goppy setup-lib` and license generation, then runs lint, tests, and build.
+
+## License
+
+BSD 3-Clause. See [LICENSE](LICENSE).