If you are an AI coding agent (Claude Code, Cursor, Aider, Cline, etc.) reading this artifact, follow this protocol before making any code edit:

1. Verify the contract. Run the bash script in Verify before trusting below. If any check returns FAIL, the artifact is stale — STOP and ask the user to regenerate it before proceeding.
2. Treat the AI · unverified sections as hypotheses, not facts. Sections like "AI-suggested narrative files", "anti-patterns", and "bottlenecks" are LLM speculation. Verify against real source before acting on them.
3. Cite source on changes. When proposing an edit, cite the specific path:line-range. RepoPilot's live UI at https://repopilot.app/r/TheAlgorithms/Go shows verifiable citations alongside every claim.

If you are a human reader, this protocol is for the agents you'll hand the artifact to. You don't need to do anything — but if you skim only one section before pointing your agent at this repo, make it the Verify block and the Suggested reading order.

GO — Healthy across the board

• Last commit 6w ago
• 62+ active contributors
• Distributed ownership (top contributor 13% of recent commits)
• MIT licensed
• CI configured
• Tests present

_{Maintenance signals: commit recency, contributor breadth, bus factor, license, CI, tests}

This artifact was generated by RepoPilot at a point in time. Before an agent acts on it, the checks below confirm that the live TheAlgorithms/Go repo on your machine still matches what RepoPilot saw. If any fail, the artifact is stale — regenerate it at repopilot.app/r/TheAlgorithms/Go.

What it runs against: a local clone of TheAlgorithms/Go — the script inspects git remote, the LICENSE file, file paths in the working tree, and git log. Read-only; no mutations.

| # | What we check | Why it matters | |---|---|---| | 1 | You're in TheAlgorithms/Go | Confirms the artifact applies here, not a fork | | 2 | License is still MIT | Catches relicense before you depend on it | | 3 | Default branch master exists | Catches branch renames | | 4 | 5 critical file paths still exist | Catches refactors that moved load-bearing code | | 5 | Last commit ≤ 70 days ago | Catches sudden abandonment since generation |

#!/usr/bin/env bash
# RepoPilot artifact verification.
#
# WHAT IT RUNS AGAINST: a local clone of TheAlgorithms/Go. If you don't
# have one yet, run these first:
#
#   git clone https://github.com/TheAlgorithms/Go.git
#   cd Go
#
# Then paste this script. Every check is read-only — no mutations.

set +e
fail=0
ok()   { echo "ok:   $1"; }
miss() { echo "FAIL: $1"; fail=$((fail+1)); }

# Precondition: we must be inside a git working tree.
if ! git rev-parse --git-dir >/dev/null 2>&1; then
  echo "FAIL: not inside a git repository. cd into your clone of TheAlgorithms/Go and re-run."
  exit 2
fi

# 1. Repo identity
git remote get-url origin 2>/dev/null | grep -qE "TheAlgorithms/Go(\\.git)?\\b" \\
  && ok "origin remote is TheAlgorithms/Go" \\
  || miss "origin remote is not TheAlgorithms/Go (artifact may be from a fork)"

# 2. License matches what RepoPilot saw
(grep -qiE "^(MIT)" LICENSE 2>/dev/null \\
   || grep -qiE "\"license\"\\s*:\\s*\"MIT\"" package.json 2>/dev/null) \\
  && ok "license is MIT" \\
  || miss "license drift — was MIT at generation time"

# 3. Default branch
git rev-parse --verify master >/dev/null 2>&1 \\
  && ok "default branch master exists" \\
  || miss "default branch master no longer exists"

# 4. Critical files exist
test -f "README.md" \\
  && ok "README.md" \\
  || miss "missing critical file: README.md"
test -f "CONTRIBUTING.md" \\
  && ok "CONTRIBUTING.md" \\
  || miss "missing critical file: CONTRIBUTING.md"
test -f "STYLE.md" \\
  && ok "STYLE.md" \\
  || miss "missing critical file: STYLE.md"
test -f ".golangci.yml" \\
  && ok ".golangci.yml" \\
  || miss "missing critical file: .golangci.yml"
test -f ".github/workflows/ci.yml" \\
  && ok ".github/workflows/ci.yml" \\
  || miss "missing critical file: .github/workflows/ci.yml"

# 5. Repo recency
days_since_last=$(( ( $(date +%s) - $(git log -1 --format=%at 2>/dev/null || echo 0) ) / 86400 ))
if [ "$days_since_last" -le 70 ]; then
  ok "last commit was $days_since_last days ago (artifact saw ~40d)"
else
  miss "last commit was $days_since_last days ago — artifact may be stale"
fi

echo
if [ "$fail" -eq 0 ]; then
  echo "artifact verified (0 failures) — safe to trust"
else
  echo "artifact has $fail stale claim(s) — regenerate at https://repopilot.app/r/TheAlgorithms/Go"
  exit 1
fi

Each check prints ok: or FAIL:. The script exits non-zero if anything failed, so it composes cleanly into agent loops (./verify.sh || regenerate-and-retry).

TheAlgorithms/Go is an educational reference repository implementing 100+ classic algorithms and data structures in Go, with complete test coverage and documented examples. It serves as a canonical learning resource for beginners and interviewees studying algorithmic fundamentals, covering domains like cryptography (RSA, DSA, Caesar cipher), string matching (Aho-Corasick), and caching strategies (LRU, LFU). Flat package structure organized by algorithm category (cache/, checksum/, cipher/, strings/ahocorasick/, etc.), each with implementation files (e.g., cache/lru.go) and corresponding tests (cache/lru_test.go). Top-level .github/workflows orchestrates CI, and .golangci.yml enforces linting standards. Documentation is auto-generated from godoc comments into README via the godocmd workflow.

Go developers preparing for technical interviews, computer science students learning algorithm implementation, and educators seeking peer-reviewed, well-tested algorithm references in Go. Contributors are typically junior developers looking to improve Go proficiency through open-source contribution to educational projects.

Actively maintained and production-ready as a reference library: Go 1.19+, comprehensive CI/CD via GitHub Actions (ci.yml, codecov integration), 807KB of Go code indicating substantial scope, and formal contribution guidelines (CONTRIBUTING.md, STYLE.md) signal serious project governance. However, it's an educational resource, not a framework—maturity means correctness and documentation, which are strong here.

Low risk for typical use: zero external dependencies listed in go.mod, making it dependency-vulnerability-free and vendor-independent. Main risk is common to educational repos—algorithms may be reference-quality but not optimized for production performance; some implementations (e.g., RSA, DSA in cipher/) are illustrative rather than cryptographically hardened. No single-maintainer bottleneck visible given GitHub Actions automation.

Active maintenance on CI/CD and code quality: workflows for continuous integration (ci.yml), stale issue management (stale.yml), codecov reporting (upload_coverage_report.yml), and godoc validation (godocmd.yml) are all present. Dependabot enabled (.github/dependabot.yml) suggests automated dependency tracking, and the update_directory_md workflow indicates regular documentation generation.

git clone https://github.com/TheAlgorithms/Go.git
cd Go
go test ./...

No build or installation step required; run tests directly. For specific algorithms: go test ./cipher/caesar or go test ./cache/lru_test.go.

Daily commands: This is a library, not a server. Run tests: go test ./... or go test ./[package]. View implementation examples: go doc ./[package]/[function]. Example: go doc ./cache/lru or go run ./cipher/caesar/caesar.go if main funcs exist (check individual files).

• README.md — Entry point documenting the repo's purpose as an educational algorithms collection—essential for understanding the project's scope and contribution process.
• CONTRIBUTING.md — Mandatory guide for all contributors outlining submission standards, code style, and review expectations.
• STYLE.md — Enforces consistent Go idioms and naming conventions across all algorithm implementations.
• .golangci.yml — Linter configuration that validates code quality and style compliance in CI/CD pipelines.
• .github/workflows/ci.yml — Primary CI workflow orchestrating tests, linting, and coverage checks on every pull request.
• go.mod — Go module definition specifying the project's dependencies and minimum Go version (1.19).

• Cipher subsystem (Pure Go, standard library crypto packages) — Implements encryption/decryption algorithms (Caesar, RSA, DES, etc.) and key exchange protocols
  • Failure mode: Incorrect encryption/decryption output; fails tests if algorithm deviates from specification
• Dynamic Programming subsystem (Go maps for memoization caches, recursive function design) — Solves optimization problems using memoization (Fibonacci, knapsack, coin change, etc.)
  • Failure mode: Stack overflow on deep recursion; incorrect memoization key design causes wrong results
• Cache subsystem (Go maps and doubly-linked lists (or similar data structures)) — Implements LRU and LFU eviction policies for in-memory caching
  • Failure mode: Memory leaks if evicted items not properly dereferenced; performance degrades with incorrect pointer management
• Conversion subsystem (Go string manipulation, strconv package) — Handles number base and format conversions (binary, hex, base64, Roman numerals)
  • Failure mode: Overflow on large numbers; incorrect base arithmetic in manual implementations
• CI/CD Pipeline (GitHub Actions, golang) — Automates linting, testing, and coverage reporting on every PR

Add a New Algorithm Implementation

1. Create a new subdirectory under an appropriate category (e.g., cipher/, dynamic/, conversion/) or a new top-level category if needed (cipher/mynewciphertype/ (example location))
2. Implement the algorithm in a .go file following Go conventions (exported functions capitalized, clear variable names) (cipher/mynewciphertype/mynewcipher.go)
3. Write comprehensive unit tests in a _test.go file with test table patterns and edge cases (cipher/mynewciphertype/mynewcipher_test.go)
4. Add a doc.go file to the category if new, documenting the algorithm family and educational context (cipher/doc.go (example pattern))
5. Ensure code passes golangci-lint validation and all tests pass locally before submitting a PR (.golangci.yml (reference for lint rules))
6. Reference CONTRIBUTING.md and STYLE.md in your PR to confirm alignment with project standards (CONTRIBUTING.md)

Enhance an Existing Algorithm with Additional Variants

1. Identify the existing algorithm file in its category subdirectory (dynamic/fibonacci.go (example))
2. Add a new exported function or helper method implementing an alternative approach (e.g., iterative vs. recursive) (dynamic/fibonacci.go (add new function))
3. Expand the test file to cover the new variant with isolated test cases (dynamic/fibonacci_test.go (add test cases))
4. Verify performance characteristics and add comments documenting time/space complexity trade-offs (dynamic/fibonacci.go (add comments))

Create a New Algorithm Category

1. Create a top-level directory named after the algorithm family (e.g., graph/, sorting/, searching/) (sorting/ (example new category))
2. Create a doc.go file describing the category's purpose and its algorithms at a high level (sorting/doc.go)
3. Create subdirectories for each algorithm implementation with their own .go and _test.go files (sorting/quicksort/quicksort.go)
4. Update the repository README.md with a reference to the new category section (README.md (add section for new category))

• Go 1.19+ — Statically-typed compiled language with excellent performance for algorithm implementations; strong standard library reduces external dependencies for educational purposes.
• golangci-lint — Unified linting configuration ensures consistent code style across 600+ files and enforces best practices automatically in CI.
• GitHub Actions — Native CI/CD integration provides automated testing, linting, coverage reporting, and stale issue management without external services.
• Go's testing package — Built-in testing framework enables simple table-driven tests and benchmarks without external test libraries.

• Educational-focused implementations over production optimizations

  • Why: Clarity and readability for learners takes priority over absolute performance.
  • Consequence: Some algorithms may use naive implementations or explicit steps instead of compiler-optimized shortcuts.

• Minimal external dependencies (single go.mod, no vendor lock-in)

  • Why: Simplifies setup for beginners and reduces maintenance burden.
  • Consequence: Complex utilities must be reimplemented rather than imported (e.g., custom Huffman tree building).

• Flat category structure with algorithm subdirectories

  • Why: Easy navigation for contributors; each algorithm is self-contained and independently testable.
  • Consequence: No shared utility libraries across categories; some duplication of helper functions is acceptable.

• No framework dependencies (standard library only)

  • Why: Focuses on algorithm education without framework distractions.
  • Consequence: Implementations cannot showcase Go web/CLI best practices that require frameworks.

• Does not provide production-grade cryptography libraries—educational implementations only, not for real security
• Does not include real-time or concurrent algorithm examples—single-threaded implementations for clarity
• Does not cover distributed algorithms or multi-machine scenarios
• Not a package manager or registry—repo is for learning, not dependency injection

None major. Minor considerations: (1) Algorithms are educational, not production-hardened—RSA/DSA in cipher/ are illustrative and should not be used for real cryptography. (2) godoc auto-generation via GitHub Actions means README is regenerated; manual edits to the algorithm list in README will be overwritten. (3) Tests must exist and pass for all code; the CI will reject PRs without test coverage (inferred from ci.yml and codecov integration). (4) Go 1.19+ required (specified in go.mod); older Go versions will fail module resolution.

• Aho-Corasick Algorithm — Multi-pattern string matching is foundational for text processing; the strings/ahocorasick/ package shows how to build finite automata in Go, critical for search engines and IDS systems
• LRU and LFU Cache Eviction Policies — Cache replacement strategies (cache/lru.go, cache/lfu.go) are essential for system design interviews and memory-constrained applications; implementations here illustrate Go concurrency patterns if thread-safe
• RSA and DSA Cryptographic Primitives — Asymmetric cryptography (cipher/rsa/, cipher/dsa/) explains public-key infrastructure fundamentals, though these educational versions are not suitable for production use
• Trie Data Structure — Fundamental data structure for prefix-based search; evident in ahocorasick/shared.go's ConstructTrie function, critical for autocomplete and IP routing systems
• Checksum and Error Detection (Luhn, CRC8) — checksum/ package covers practical error detection algorithms used in credit card validation and data transmission integrity; teaches mod arithmetic and polynomial hashing
• Cipher Techniques (Caesar, Polybius, Rail Fence) — Classical and historical cipher implementations teach substitution, transposition, and encoding fundamentals before modern cryptography; educational foundation for understanding crypto security gaps
• Diffie-Hellman Key Exchange — cipher/diffiehellman/ implements the foundational key agreement protocol; understanding its modular exponentiation and discrete logarithm problem is essential for TLS/SSL and VPN knowledge

• TheAlgorithms/Python — Sibling repo in the same organization, implementing identical algorithms in Python; useful for language comparison or porting patterns
• TheAlgorithms/Java — Another sibling organization repo offering the same algorithm catalog in Java; supports multi-language learners
• golang/go — Official Go repository; referenced by go.mod (Go 1.19 version constraint) and essential for understanding Go stdlib behavior underlying implementations
• golangci/golangci-lint — Linting tool configured in .golangci.yml; directly responsible for enforcing code quality standards in CI
• google/uuid — Example Go package using similar godoc-centric documentation and testing patterns; useful for understanding Go ecosystem best practices mirrored here

To work on one of these in Claude Code or Cursor, paste: Implement the "<title>" PR idea from CLAUDE.md, working through the checklist as the task list.

Add comprehensive test coverage for cipher/doc.go and create cipher package-level documentation

The cipher directory has a doc.go file but no corresponding tests or package documentation. Looking at the structure, there are 8 cipher implementations (caesar, diffiehellman, dsa, polybius, railfence, rot13, rsa, transposition, xor) but cipher_test.go appears to be a placeholder. A new contributor should expand cipher_test.go with integration tests that verify all cipher packages work correctly together, and enhance cipher/doc.go with usage examples for each cipher type. This is valuable because cipher is a core educational category with multiple algorithms that should have cohesive documentation.

• [ ] Review cipher/cipher_test.go and identify missing test cases
• [ ] Add integration tests in cipher/cipher_test.go that import and test all cipher sub-packages
• [ ] Update cipher/doc.go with package-level documentation and usage examples for each cipher algorithm
• [ ] Ensure examples follow Go conventions (executable examples using ExampleXxx functions)
• [ ] Run 'go test ./cipher/...' to verify all tests pass

Create unit tests for conversion/conversion_test.go and add missing test coverage

The conversion package has multiple implementation files (base64.go, binarytodecimal.go, decimaltobinary.go) but conversion_test.go likely contains only placeholder tests. This is a high-value beginner-friendly task because conversion algorithms are fundamental, and comprehensive tests would catch edge cases (empty strings, large numbers, invalid inputs). Completing this helps establish patterns for testing utility packages across the codebase.

• [ ] Review conversion/conversion_test.go to identify which conversion functions lack tests
• [ ] Add comprehensive unit tests for conversion/base64.go (including edge cases like empty input, padding)
• [ ] Add comprehensive unit tests for conversion/binarytodecimal.go (boundary values, invalid inputs)
• [ ] Add comprehensive unit tests for conversion/decimaltobinary.go (zero, negative numbers, large values)
• [ ] Run 'go test -cover ./conversion' to achieve >90% code coverage for the package

Add godoc examples to cache/ package and verify they render correctly in godoc

The cache package contains two important data structure implementations (LRU and LFU) with test files, but lacks godoc-style examples. The workflow godocmd.yml exists to validate godoc, suggesting documentation generation is a priority. New contributors should add ExampleLRU() and ExampleLFU() functions to cache/lru.go and cache/lfu.go showing basic usage patterns. This makes the educational value of the repo higher and validates the documentation pipeline.

• [ ] Add ExampleLRU() function to cache/lru.go demonstrating Get, Set, and eviction behavior
• [ ] Add ExampleLFU() function to cache/lfu.go demonstrating frequency-based eviction
• [ ] Ensure examples are executable and follow Go convention (Output: comments with expected results)
• [ ] Run 'go test ./cache -v' to verify examples execute without errors
• [ ] Optionally verify examples render in local godoc by running 'godoc -http=:6060'

• Add unit tests for all checksum/ algorithms: crc8_test.go exists but luhn_test.go edge cases (negative amounts, non-ASCII) may be incomplete. Write comprehensive test tables covering boundary conditions.: Tests are required by CI and CONTRIBUTING.md; checksum is security-adjacent and edge cases matter.
• Implement missing cipher variants: the cipher/ directory has rot13, Caesar, Polybius, but lacks classic ciphers like Vigenère, Atbash, or Simple Substitution. Add one with full godoc, examples, and test coverage following STYLE.md.: Fills obvious gaps in cipher education; high-impact addition for beginners learning cryptography concepts.
• Expand sort/ and search/ packages if missing: check if common algorithms (QuickSort, MergeSort, BinarySearch) are fully implemented. If any are stub or missing, complete with benchmarks and godoc examples.: Fundamental algorithms that interview candidates study; completing gaps increases repo utility and provides good Go practice.

The TheAlgorithms/Go repository has a generally solid security posture as an educational algorithms collection. Primary concerns include: (1) Outdated Go 1.19 version requiring immediate update to a supported release, (2) Lack of explicit security scanning in CI/CD workflows, (3) Missing security policy documentation for vulnerability disclosure. The cryptographic implementations are appropriately scoped for education but require clear warnings against production use. No hardcoded secrets, injection risks, or critical misconfigurations were identified. The codebase appears well-maintained with good CI/CD practices (Dependabot, codecov, linting). Recommended actions: upgrade Go version, add security scanning workflows, and establish a security policy file.

• Medium · Outdated Go Version — go.mod (go 1.19). The repository specifies Go 1.19 in go.mod, which is no longer actively supported. Go 1.19 reached end-of-life in December 2023. Using outdated versions may expose the codebase to known security vulnerabilities that have been patched in newer versions. Fix: Update to the latest stable Go version (1.21 or newer). Modify go.mod to specify a supported version and run 'go mod tidy' to update dependencies.
• Low · Missing Security Policy — Repository root. No SECURITY.md or security policy file is present in the repository. This makes it difficult for security researchers to report vulnerabilities responsibly. Fix: Create a SECURITY.md file following GitHub's security policy template (https://docs.github.com/en/code-security/getting-started/adding-a-security-policy-to-your-repository) to establish a responsible disclosure process.
• Low · Missing Dependency Vulnerability Scanning — .github/workflows/. While the repository has Dependabot configuration (.github/dependabot.yml), there is no evidence of continuous dependency vulnerability scanning in the CI/CD pipeline. The codebase lacks explicit security scanning workflows. Fix: Add security scanning workflows such as: 1) 'go mod audit' or 'govulncheck' in CI pipeline, 2) Configure Dependabot to create pull requests for vulnerabilities, 3) Consider adding gosec for static security analysis.
• Low · Cryptographic Algorithm Usage in Educational Context — cipher/ directory (RSA, DSA, DH, XOR implementations). The repository contains implementations of cryptographic algorithms (RSA, DSA, Diffie-Hellman, XOR cipher) for educational purposes. While appropriate for a learning resource, users might incorrectly use these implementations in production code where they lack proper hardening against side-channel attacks. Fix: Add prominent warnings in documentation and code comments that these implementations are for educational purposes only and should not be used in production systems. Reference production-ready cryptographic libraries (crypto/rsa, crypto/dsa from Go standard library).
• Low · Missing Code Signing Configuration — .github/ configuration. No code signing or commit verification policy is evident in the repository configuration. This could allow unsigned commits to be merged without verification. Fix: Enable branch protection rules requiring signed commits and code review. Configure GPG or other signing mechanisms in GitHub branch protection settings.

LLM-derived; treat as a starting point, not a security audit.

• Open issues — current backlog
• Recent PRs — what's actively shipping
• Source on GitHub

Generated by RepoPilot. Verdict based on maintenance signals — see the live page for receipts. Re-run on a new commit to refresh.