Tutorials Intermediate
Claude Code Mods: Build a Fail-Closed Bash Guard in JS
Write a Claude Code mod that blocks, asks, and logs risky shell commands, then test it.
16 min read·Kodetra Technologies
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AI Guides for Builders
How-to content for builders, indie hackers, and AI engineers. Less theory, more shipped code.
Tutorials 
Tutorials Intermediate
Codex Security CLI: Gate PRs on High Severity
Scan a PR diff with OpenAI's Codex Security, cap the spend, and fail CI on high-severity bugs.
13 min read·Kodetra Technologies
6d ago
Tutorials Intermediate
OpenAI Ultrafast: Pay 6x Only When Latency Matters
A Python router that buys Ultrafast speed only where users wait, with fallback and cost tracking.
9 min read·Kodetra Technologies
6d ago
Tutorials Intermediate
GPT-6.1 Sol Computer Use: Build a Browser Agent
Drive a real browser with GPT-6.1 Sol's batched computer tool, with guardrails.
8 min read·Kodetra Technologies
7d ago
Tutorials Intermediate
Ember-1: A/B Test Its 40% Token Savings in Python
Fireworks' Ember-1 claims 40% fewer tokens than Kimi K3. Build a harness to verify it.
8 min read·Kodetra Technologies
7d ago
Tutorials Intermediate
Stop Claude Code From Deleting Your Files
A Claude Code agent deleted 48,000 files in 103 seconds. Build the setup that stops it.
10 min read·Kodetra Technologies
8d ago
Tutorials Intermediate
Claude Code Projects: Retire an API Across 3 Repos
Set up Claude Code's new Projects beta to run coordinated, parallel AI coding threads across repos.
11 min read·Kodetra Technologies
11d ago
Tutorials Intermediate
Opus 5.5 Upgrade: Fix 4 Breaking Changes Before They 400
Opus 5.5 is 20% cheaper, but old thinking, tool_choice and computer-use code now fails. Fix it.
15 min read·Kodetra Technologies
13d ago
Tutorials Intermediate
Qwen3.8-Flash-Next: Preserved Thinking, Cheaper Agents
Qwen keeps reasoning across every turn by default. Exploit it, or pay for it.
11 min read·Kodetra Technologies
Aug 27
Tutorials Intermediate
GLM-5.3-Flash: Let Your Agent See the UI It Built
Build a render-screenshot-critique loop with GLM-5.3-Flash native vision, for pennies a run.
12 min read·Kodetra Technologies
Aug 27
Tutorials Intermediate
Anthropic SDK v1.0: The Silent httpx2 Mock Trap
Upgrade to anthropic>=1 without your respx mocks and OTel traces going quietly blind.
13 min read·Kodetra Technologies
Aug 26
Tutorials Intermediate
A2A 1.0: Sign and Verify Agent Cards Before Delegating
Publish a JWS-signed A2A v1.0 Agent Card in Python and refuse any card you cannot verify.
11 min read·Kodetra Technologies
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