Immediate result: A blameless postmortem with timeline, impact, root cause, contributing factors and owned actions.
Problem it solvesAfter an outage, the postmortem is written late, blames people and repeats the same action items.
14:02 alerts fire · 14:10 rollback tried, fails · 14:31 DB connection pool raised · 14:35 recovered
Impact: 33 minutes of failed checkouts.
Root cause: a release doubled queries per request, exhausting the 20-connection pool.
Action: load test releases at 2× peak — owner: platform team, due 15 Nov — prevent.
Postmortems written late tend to blame people and repeat last quarter's action items. This skill turns your incident notes or chat log into a blameless postmortem: a timestamped timeline, customer impact in numbers, the trigger separated from the root cause and contributing factors, what went well, and action items that each have an owner, a date and a type — prevent, detect or mitigate. Gaps in the timeline are marked as gaps rather than smoothed over. It describes systems and decisions, never individuals, which is what makes teams honest enough to learn from outages.
# Skill: Incident postmortem writer
You are running the "Incident postmortem writer" skill for me. I work as: SRE / engineering manager. What I need from you: a blameless postmortem with timeline, impact, root cause, contributing factors and owned actions.
## When I send you my incident notes, chat log or timeline, plus who was affected and for how long
1. Build a timestamped timeline from the notes.
2. State customer impact in numbers (duration, users, requests, revenue if given).
3. Separate the trigger, the root cause and contributing factors using '5 whys'.
4. Write action items that are specific, owned and dated.
## Reply in this format
- Summary
- Impact
- Timeline
- Root cause
- Contributing factors
- What went well
- Action items table: action, owner, due, type (prevent / detect / mitigate)
## Rules
- Blameless language: describe systems and decisions, not individuals.
- Mark gaps in the timeline as gaps.
- Use only the facts I give you; mark anything you had to assume with [ASSUMPTION].
- If something essential is missing, ask me one short question, then continue.
- No preamble or filler: start with the result.
Confirm you're ready in one line, then wait for me to send my incident notes, chat log or timeline, plus who was affected and for how long.Then sendYour incident notes, chat log or timeline, plus who was affected and for how long. For example: 14:02 alerts fire · 14:10 rollback tried, fails · 14:31 DB connection pool raised · 14:35 recovered
Upload it to Claude, add it to ChatGPT's Codex app, clone it into Claude Code, or download the SKILL.md for any agent. Full guide with screenshots →
Download the ZIP and upload it in Claude. Claude then uses the skill on its own whenever a request matches.
Download ZIP
OpenAI's Codex app reads the same SKILL.md format. Copy the skill into your Codex skills folder:
$ git -c http.version=HTTP/1.1 clone https://scienceofapps.com/skills/ai-skills.git
$ cp -r ai-skills/incident-postmortem ~/.codex/skills/
Clone the library and copy this skill into your Claude Code skills folder.
$ git -c http.version=HTTP/1.1 clone https://scienceofapps.com/skills/ai-skills.git
$ cp -r ai-skills/incident-postmortem ~/.claude/skills/~/.claude/skills/ for all projects, or .claude/skills/ inside one project.Download the skill file and put it in a folder named after the skill.
Download SKILL.md~/.claude/skills/incident-postmortem/SKILL.md.Repositoryscienceofapps.com/skills/ai-skills.git · all 200 skills, one folder each, plain git over HTTPS
After an outage, the postmortem is written late, blames people and repeats the same action items. The skill fixes that: a blameless postmortem with timeline, impact, root cause, contributing factors and owned actions.
Copy the skill and paste it as the first message of a new chat, then send your input. To keep it, paste it into a ChatGPT Project or custom GPT, a Claude Project or a Gemini Gem, or upload the SKILL.md file as a Claude Skill.
Send your incident notes, chat log or timeline, plus who was affected and for how long. If something essential is missing, the skill asks you one short question and then continues.
Yes. It's free to copy, use and adapt, with no sign-up, and works in the free versions of ChatGPT, Claude, Gemini and Copilot.
ProblemPorting code between languages by hand introduces subtle behaviour changes.
Python → TypeScript: def avg(xs): return sum(xs) / len(xs)
const avg = (xs: number[]) => xs.length ? xs.reduce((a, b) => a + b, 0) / xs.length : NaN;
Difference: Python raises ZeroDivisionError on []; this returns NaN — throw if you need parity.
Immediate resultIdiomatic code in the target language with notes on every behaviour that differs.
ProblemBig technical decisions get made in meetings and forgotten, so the team re-argues them a year later.
Choosing a queue: Redis streams vs RabbitMQ vs SQS for 2k jobs/min, team of 4, on AWS
Decision: Amazon SQS.
Why: managed, scales past 2k/min, the team already runs on AWS.
Harder: local development needs LocalStack. Revisit if we leave AWS.
Immediate resultAn ADR with context, options considered, the decision and its consequences, ready to commit.
ProblemThousands of log lines hide the one pattern that explains the outage.
500 lines of nginx + app logs from 09:00–09:20
upstream timed out (110) — 212 lines, first 09:04:11
DB pool exhausted — 198 lines, first 09:04:09 (2 s earlier)
Likely culprit: database, not nginx. Next: check slow query log 09:03–09:05.
Immediate resultGrouped error patterns with counts, first-seen times and the most likely culprit.
All 20 software engineering skillsAll 200 skillsRead it in the articleProve it: AI for Software Developers Certification (free test)
60 research-backed principles in 6 categories — what each one means, why it works on the human brain and how to use it on your own screens. Written by Sushant Singh, founder of Science of Apps, who has scaled consumer apps to lacs of users and spent 10+ years leading product across startups and digital businesses in the US, EU & India.
110 real paywalls from top apps, taken apart, rated out of 5 and decoded with the Laws of UX — plus the frameworks, copy and checklists to ship your own. By Sushant Singh, founder of Science of Apps.