OPEN tech stack
OPEN builds mostly with Python, TypeScript, JavaScript, Apex. Its stack also includes AWS, PoC Library, OpenAI, PostgreSQL. AWS is named in 9 of the 13 job postings OPEN published in the last 12 months (69%). Counted by Alion from the job postings of OPEN, updated Sep 30, 2026.
What programming languages does OPEN use?
Python is named in 54% of job postings at OPEN, followed by TypeScript (38%), JavaScript (38%), Apex (8%).
What frameworks and libraries does OPEN use?
PoC Library is named in 46% of job postings at OPEN, followed by Django (31%), Django REST Framework (23%), Playwright (23%).
Django
4 31%
Django REST Framework
3 23%
Playwright
3 23%
Vitest
3 23%
Vue.js
3 23%
LangChain
2 15%
Next.js
2 15%
Show all (13)
What databases does OPEN use?
PostgreSQL is named in 31% of job postings at OPEN, followed by Amazon Aurora (8%), BigQuery (8%), Google BigQuery (8%).
BigQuery 
What cloud and platforms does OPEN use?
AWS is named in 69% of job postings at OPEN, followed by OpenAI (38%), AWS Lambda (31%), GitHub (31%).
AWS
9 69%
AWS Lambda
4 31%
GitHub
4 31%
Azure
3 23%
GCP
2 15%
AWS Bedrock
1 8%
Show all (15)
What developer tools does OPEN use?
Docker is named in 38% of job postings at OPEN, followed by Vite (23%), ESLint (15%), Git (15%).
Docker
5 38%
Vite
3 23%
ESLint
2 15%
Git
2 15%
Mypy
2 15%
Prettier
2 15%
Terraform
2 15%
flake8
2 15%
Show all (11)
What AI and ML technologies does OPEN use?
Claude is named in 38% of job postings at OPEN, followed by LLM (38%), Gemini (15%), ChatGPT (8%).
Which engineering practices does OPEN ask for?
CI/CD is named in 23% of job postings at OPEN, followed by AI Agents (15%), OCR (15%), RAG (15%).
What does each OPEN team work with?
The technologies each team's postings require most often, with the number of postings that require them.
Solutions
5 postingsAI/ML
3 postingsHow does your stack fit OPEN?
How much does OPEN pay by technology?
Median stated pay of the postings that name each technology, against the median of all OPEN postings with stated pay: $790k across 11 postings.
| Technology | Postings with pay | Median | vs company median |
|---|---|---|---|
| AWS | 7 | $790k | 0% |
| PoC Library | 6 | $625k | −21% |
| Python | 5 | $790k | 0% |
How is the OPEN stack changing?
Read from the dates of the postings themselves: a technology is new when the first posting that names it appeared in the last six months, rising or falling when its share of postings moved between the last two quarters.
How modern is the OPEN stack?
OPEN scores 90 out of 100 (Cutting-edge). The score averages how current each technology in the stack is and adds weight for AI adoption. AI technologies in the stack: 4; legacy ones: 0.
Companies with a stack like OPEN
Questions about the OPEN tech stack
What programming languages does OPEN use?
The languages named in OPEN job postings are Python (54%), TypeScript (38%), JavaScript (38%), Apex (8%), Kotlin (8%), as a share of the 13 postings of the last 12 months.
Does OPEN use PoC Library?
Yes. PoC Library is named in 6 of 13 job postings (46%) and required in 6 of them.
What cloud and platforms does OPEN use?
The cloud and platforms named in OPEN job postings are AWS (9), OpenAI (5), AWS Lambda (4) (postings in brackets).
What skills do you need for a Solutions job at OPEN?
Solutions postings at OPEN most often require AWS (4), Claude (3), Django (3), Docker (3), out of 5 postings in the last 12 months.
Is the OPEN tech stack changing?
Yes. Django REST Framework, Playwright, Vite, Vitest first appeared in OPEN job postings in the last six months.
How modern is the OPEN tech stack?
OPEN scores 90 out of 100 (Cutting-edge). The score averages how current each technology in the stack is and adds weight for AI adoption. AI technologies in the stack: 4; legacy ones: 0.
How does Alion know the OPEN tech stack?
Alion reads every job posting OPEN publishes and tags the technologies each one names. The figures on this page count the 13 postings of the last 12 months and were updated on Sep 30, 2026.
Method and citation
Alion reads every job posting the company publishes and tags the technologies each one names. Shares count the postings of the last 12 months, open and closed; the company's own products are counted apart. How we count
Alion, "OPEN tech stack: 57 technologies from 13 job postings", as of Sep 30, 2026. https://alion.io/company/open-co-jp/technologies